Congestive heart failure is inability of the heart to pump an adequate amount of blood to the systemic circulation to meet the body’s metabolic demands. Causes of heart failure can be classified according to the following changes:

1. Increased volume, especially with left-to-right shunts that cause the right ventricle to hypertrophy in order to compensate for the additional blood volume

2. Increased afterload, primarily resulting from obstructive lesions, such as valvular stenosis or coarctation of the aorta

3. Myocardial factors that affect the contractility of the muscle fibers, such as myocardial ischemia from severe anemia or asphyxia, heart block, acidemia, and low levels of potassium, glucose, calcium, or magnesium

4. High cardiac output demands, in which the body’s need for oxygenated blood exceeds the heart’s cardiac output (even though the volume may be normal), such as in obstructive lung disease, hyperthyroidism, and severe anemia

In children CHF occurs most frequently secondary to structural abnormalities that result in increased blood volume and pressure. It is a symptom caused by an underlying cardiac defect, not a disease in itself, since it is usually the result of an excessive workload imposed on a normal myocardium. The majority of children who experience CHF are infants, and more than 50% are younger than I month of age.

Pathophysiology

Heart failure is often separated into two classifications: right-sided or left-sided failure. In right-sided failure the right ventricle is unable to pump blood into the pulmonary artery, resulting in less blood being oxygenated by the lungs and increased pressure in the right atrium and systemic venous circulation. Systemic venous hypertension causes edema on the extremities. In left–sided failure the left ventricle is unable to pump blood into the systemic circulation, resulting in increased pressure in the left atrium and pulmonary veins. The lungs become congested with blood, causing elevated pulmonary pressures and pulmonary edema.

Although each type produces different systemic/pulmonary artery alterations, clinically it is unusual to observe solely right- or left-sided failure. Since both sides of the heart are dependent on adequate function of the other side, failure of one chamber causes a reciprocal change in the opposite chamber. For example, in left-sided failure increase in pulmonary vascular congestion will cause increased pressure in the right ventricle, resulting in right ventricular hypertrophy, decreased myocardial efficiency, and eventually pooling of blood in the systemic venous circulation.

Compensatory mechanisms

CHF is actually failure of compensatory mechanisms to increase cardiac function in accordance with metabolic requirements. Since most of the signs and symptoms result from decompensation, one must first look at the compensatory processes that attempt to preserve cardiac function.

Sympathetic stimulation. When the cardiac output falls, the atrial and venous stretch receptors and the aortic and carotid baroreceptors stimulate the sympathetic nervous system, which exerts two major effects. It increases the force and rate of myocardial contraction, resulting in a more efficient pumping action. It also increases venous return by increasing the tone of blood vessels and decreasing peripheral circulation to the limbs, splanchnic bed (viscera), and kidneys.

Stimulation of the sympathetic cholinergic fibers in the skin causes increased sweating, which is especially prominent on the scalp during periods of exertion, such as crying or feeding.

Renal system. Reduced renal blood flow from sympathetic stimulation has a profound effect on kidney function and results in changes aimed at increasing venous return through increased blood volume. First, there is an increase in aldosterone production in response to increased renin secretion from decreased renal blood flow and sympathetic stimulation. Aldosterone increases the rate of sodium reabsorption by the distal tubules, promoting osmosis of water into the blood. The absorbed sodium increases the osmotic concentration of the extracellular fluid, stimulating release of antidiuretic hormone from the hypophysis, which promotes increased water reabsorption by the tubules.

Clinical manifestations

Despite compensatory mechanisms, the heart may be unable to maintain an adequate cardiac output. Decreased blood flow to the kidneys continues to stimulate sodium and water reabsorption, leading to hypervolemia, increased workloadon the heart, and congestion in the pulmonary and systemic circulations. Because these hemodynamic changes occur at different times, the signs and symptoms can vary.

Impaired myocardlal function. One of the earliest signs of compensation and decompensation is tachycardia (sleeping heart rate above 160 beats/minute in infants), as a direct result of sympathetic stimulation. It is elevated even during rest but becomes markedly rapid during the slightest exertion.

Increased blood volume causes the ventricles to dilate, stretching the myocardial fibers until they are no longer as contractile. Ventricular dilation results in extra heart sounds, S₃ and/or S₄. The addition of these extra sounds to S₁S₂ produces a gallop rhythm. S₃ is believed to be caused by vibrations against the ventricle walls as blood flow is abruptly stopped when the dilated ventricles cao longer accommodate the volume. It is heard immediately after the second heart sound (ventricular diastolic gallop). S₄ is believed to be caused by atrial contraction in response to ventricular resistance during filling of the ventricles. It occurs just before the first heard sound (atrial presystolic gallop). The presence of S₃ and S₄ is called a summation gallop. Each is best heard at the apex.

Variations in the strength of ventricular contraction result in pulsus alternans, regular alternation of one strong beat and one weak one. It is best detected by palpating the pulse while taking the blood pressure. The increased pressure from the inflated cuff occludes the weak beats, so that only the stronger beats are counted. As a result, the pulse is half the actual rate.

Cardiomegaly results from dilation of the ventricle to accommodate increasing volumes of blood and from hypertrophy, as a result of persistent lengthening and thickening of the myocardial fibers. Although hypertrophy decreases the contractility of the fibers, it is partially compensated by an increase in muscle mass.

Decreased cardiac output results in poor peripheral perfusion, which is manifest by cold extremities, weak pulses, low blood pressure, mottled skin, and eventually growth retardation.

Pulmonary congestion. As the left ventricle fails, blood volume and pressure increase in the left atrium, pulmonary veins, and lungs. Eventually the pulmonary capillary pressure exceeds the plasma osmotic pressure, forcing fluid into tissues, causing pulmonary edema. The increased pressure also decreases the compliance (expansion) of the lungs.

Dyspnea is the earliest signs of failure and is thought to be caused by a decrease in the distensibility of the lungs. as a result, additional muscles must be used for respiration, causing costal retractions. Initially dyspnea may only be evident on exertion but may progress to the point that even slight activity results in labored breathing. In infants dyspnea at rest is a prominent sign and may be accompanied by flaring nares.

Tachypnea (respiratory rate above 60 breaths/minute in infants) occurs in response to decreased lung compliance. Inability to feed with resultant weight loss is primarily a result of tachypnea and dyspnea on exertion.

Orthopnea (dyspnea in the recumbent position) is caused by increased blood flow to the heart and lungs from the extremities. It is relieved by sitting up, because blood pools in the lower extremities, decreasing venous return. In addition, this position decreases pressure from the abdominal organs on the diaphragm. In infants orthopnea may be evident in their inability to lie supine and their desire to be held upright.

Paroxysmal nocturnal dyspnea (PND) is a severe shortness of breath that occurs shortly after falling asleep. It is a result of reabsorption of fluid (from dependent edema), which increases blood volume, producing more severe pulmonary congestion.

Edema of the bronchial mucosa may produce cardiac wheezing from obstruction to airflow. Mucosal swelling and irritation result in a persistent, dry, hacking cough. As pulmonary edema increases, the cough may be productive from increased secretions. Pressure on the laryngeal nerve results in hoarseness. A late sign of heart failure is gasping and grunting respirations. An uncommon sign in infants is rales.

Cyanosis may occur without a right-to-left shunt and is the result of impaired respiratory gas exchange. On exertion, such as crying or feeding, the infant may experience mottling of the skin or generalized transient duskiness. Extreme pallor or persistent duskiness is an ominous sign of CHF.

Systemic congestion. Systemic congestion is a primary consequence of right-sided failure from inability of the right ventricle to eject blood into the pulmonary circulation, resulting in increased pressure and pooling of blood in the venous circulation. As was explained earlier, it can result as a late consequence of left-sided failure.

Hepatomegaly is usually the earliest sign of failure and occurs from pooling of blood in the portal circulation and transudation of fluid into the hepatic tissues. The liver may be tender on palpation and its size is an indication of the course of heart failure.

Edema forms as the sodium and water retention cause systemic vascular pressure to rise. The earliest sign is weight gain. However, as additional fluid accumulates, it leads to swelling of soft tissue that is dependent and favors the flow of gravity, such as the sacrum and scrotum when recumbent and loose periorbital tissues. In infants edema is usually generalized and difficult to detect. Gross fluid accumulation may produce ascites and pleural effusions.

Distended neck and peripheral veins, which are uncommon in infants, result from a consistently elevated central venous pressure. Normally neck and hand veins collapse when the head or hands are raised above the level of the heart, since the blood drains by gravity back to the heart.

However, when the venous pressure is high, it prevents the back flow of blood, causing the veins to remain distended.

Diagnostic evaluation

Diagnosis is made on clinical symptoms such as dyspnea (especially when at rest), flaring nares, moist grunting respirations, subcostal retractions, tachycardia, activity intolerance (particularly during feeding), excessive sweating, and unexplained weight gain from edema. Since the signs of pulmonary congestion from heart failure resemble respiratory infections, it is imperative to differentiate between the two. Signs selectively indicative of CHF are cardiac enlargement, edema, sweating, hepatomegaly, and auscultatory findings such as tachycardia, gallop rhythm, and pulsus alternans.

Care for children

The objectives of nursing care are to (1) assist in measures to improve cardiac function, (2) decrease cardiac demands, (3) reduce respiratory distress, (4) maintain nutritional status, (5) assist in measures to promote fluid loss, and (6) provide emotional support. Although the objectives are the same, the interventions differ depending on the child’s age, especially with infants as compared to older children.

Assist in measures to Improve cardiac function. The nurse’s responsibility in administering digitalis includes observing for signs of toxicity, calculating the correct dosage, and instituting parental teaching regarding drug administration at home.

Cardiac arrest

Clinical manifestation

Apnoea, absence of pulse, loss of consciousness, dilatation of pupils, areflexia, cyanosis. The duration of the clinical death depends on the time, during which the brain is without blood supply, and the body temperature. When the body temperature is normal –effective resuscitation is possible during 5 min; at the body temperature 36-32^o C- the resuscitation will be effective during 8 min, 32-28^o C – 15 min, 28-18^oC – 45 min.

Emergency Aid

I. To provide upper respiratory tract passage.

1. Put the child on the back on the hard surface.

2. Put the pillow under the neck to get the maximal extension of the head.

3. Put mandibulla forward

4. Clean the upper respiratory tract by the pump.

II. Artificial ventilation of the lungs is carried out either by mouth to mouth respiration, or by mouth to nose, with the help of breathing pump.

After making deep breath and through the cotton mask, putted on the mouth, inhale the air to the mouth of the child. Nose must be closed.

The rate of inhalation is 40 per min for newborn, for infants – 30; for children over 5 years – 25; 6-14 years – 20 and for elder – 16-18 per 1 min.

Artificial ventilation of the lungs is connected with indirect massage of the heart.

In the children of the first 3 month of life-massage is done by thumb. In the children from3 months till 3 years-by 3 fingers ,in children over 5 years-by two hands which are put in cross position on the lower part of the sternum. Press on the sternum to compress the heart between the sternum and vertebral column…Iewborns sternum should be pressed down on 1-1.5cm, in children 2month-3 years-on 2.5 cm, in children 5-15 years-on 3-4 cm.

The frequency of compression is 60-100 times per 1 minute ,depending on age. During I inspiration should be made 4 compression on sternum.

The manifestations of effective resuscitation are appearance of pulse on carotids, renewal of breathing, constrictions of pupils and decreasing of cyanosis.

Putting ice or bags with cold water around the head helps to prolong time of effective resuscitation. If it’s possible you can make intubation of trachea.

Degree of heart failure

clinical symptoms

Degree

failure of right ventricle

failure o left ventricle

Breath rates

Pulse rates

Cough and rales in the lungs

The colour of the skin

Hepatomegaly

Splenomegaly

Edema, oliguria

The clinical manifestation appears during physical activity (dyspnea, tachycardia, acrocyanosis)

II A

> 30-50 %

> 15-30 %

–

+ 3 cm

–

(-)-(+)

II B

> 50-70 %

> 30-50 %

+ 3-5 cm

–

III

> 70 %

> 50 %

++, oedema of lung

> 5 cm

WHAT IS THE DIFFERENCE BETWEEN CYANOTIC AND ACYANOTIC HEART DEFECTS?

With cyanotic (blue) heart defects, the blood that is pumped around the body contains less-than-normal levels of oxygen. This causes the skin to appear bluish in colour, a condition known as cyanosis.

The most common type of cyanotic heart defect is termed tetralogy of Fallot (see diagram). This can result in for example, stenosis (narrowing) at or just beneath the pulmonary valve. This narrowing partially blocks the flow of blood from the right side of the heart to the lungs.

As a result of this condition, cyanosis may appear soon after birth, in infancy or later in childhood. In some children, the cyanosis may become severe, resulting in rapid breathing and possibly even unconsciousness.

Most children with this condition have open-heart surgery before they start going to school.

Acyanotic (pink) heart defects do not generally cause the infant or child to go blue. An example is coarctation of the aorta. The aorta is the main artery responsible for carrying blood from the heart to the rest of the body. Coarctation results in the aorta being constricted or pinched. This obstructs the blood flow mostly to the lower part of the body. It also increases blood pressure above the constriction.

With this condition symptoms usually do not show at birth, however they can begin to emerge as soon as a week after birth. A child with severe coarctation should have surgery in early childhood, after which, long-term follow up is necessary.

PULMONIC STENOSIS

Pulmonary stenosis is a congenital (present at birth) defect that occurs due to abnormal development of the fetal heart during the first 8 weeks of pregnancy.The pulmonary valve is found between the right ventricle and the pulmonary artery. It has three leaflets that function like a one-way door, allowing blood to flow forward into the pulmonary artery, but not backward into the right ventricle. With pulmonary stenosis, problems with the pulmonary valve make it harder for the leaflets to open and permit blood to flow forward from the right ventricle to the lungs. In children, these problems can include:

· a valve that has leaflets that are partially fused together.

· a valve that has thick leaflets that do not open all the way.

· the area above or below the pulmonary valve is narrowed.

There are four different types of pulmonary stenosis:

· valvar pulmonary stenosis – the valve leaflets are thickened and/or narrowed

· supravalvar pulmonary stenosis – the pulmonary artery just above the pulmonary valve is narrowed

· subvalvar (infundibular) pulmonary stenosis – the muscle under the valve area is thickened, narrowing the outflow tract from the right ventricle

· branch peripheral pulmonic stenosis – the right or left pulmonary artery is narrowed, or both may be narrowed

Pulmonary stenosis may be present in varying degrees, classified according to how much obstruction to blood flow is present. A child with severe pulmonary stenosis could be quite ill, with major symptoms noted early in life. A child with mild pulmonary stenosis may have few or no symptoms, or perhaps none until later in adulthood. A moderate or severe degree of obstruction can become worse with time.

Congenital pulmonary stenosis occurs due to improper development of the pulmonary valve in the first 8 weeks of fetal growth. It can be caused by a number of factors, though most of the time this heart defect occurs sporadically (by chance), with no clear reason evident for its development.Some congenital heart defects may have a genetic link, either occurring due to a defect in a gene, a chromosome abnormality, or environmental exposure, causing heart problems to occur more often in certain families.

Mild pulmonary stenosis may not cause any symptoms. Problems can occur when pulmonary stenosis is moderate to severe, including the following:

The right ventricle has to work harder to try to move blood through the tight pulmonary valve. Eventually, the right ventricle is no longer able to handle the extra workload, and it fails to pump forward efficiently. Pressure builds up in the right atrium, and then in the veins bringing blood back to the right side of the heart. Fluid retention and swelling may occur.
There is a higher than average chance of developing an infection in the valves of the heart known as bacterial endocarditis.

The following are the most common symptoms of pulmonary stenosis. However, each child may experience symptoms differently. Symptoms may include:

heavy or rapid breathing
shortness of breath
fatigue
rapid heart rate
swelling in the feet, ankles, face, eyelids, and/or abdomen
fewer wet diapers or trips to the bathroom

The symptoms of pulmonary stenosis may resemble other medical conditions or heart problems.

Altered hemodynamic

In case of pulmonic stenosis resistance to blood flow causes the right ventricular hypertrophy.

The child with problems related to production and circulation of blood left ventricle causes hypertrophy and increased demands for coronary blood supply. Backup of blood into the left atrium may cause increased pressure in that chamber and the pulmonary veins, resulting in pulmonary vascular congestion.

AORTIC STENOSIS

A serious form of critical may occur during the neonatal period. Symptoms of left ventricular failure respiratory distress, faint peripheral pulses, and severe physical limitations occur during the first 2 weeks of life. Children with less severe stenosis may not show signs of the defect until preadolescence. Clinical manifestations such as fainting, epigastric or anginal pain, exercise intolerance, and dizziness after prolonged standing may occur. A serious consequence is sudden death after exertion as a result of a severely ischemic heart.

A murmur is typically heard with aortic stenosis from blood flow through the valve. It is heard best at the upper right stemal border to second interspace (aortic space) and radiates to the suprasternal notch, clavicular area, and neck. Sometimes it is transmitted along the left sternal border to the apex. It is usually associated with a thrill.

The second heart sound is characteristically affected. Because the closure of the aortic valve is delayed, the normal splitting of S₂ is narrowed. With severe stenosis the left ventricular ejection may be so prolonged that the closure of the pulmonic valve occurs simultaneously or precedes that of the aortic valve. In the former instance there is no splitting. In the latter event the usual splitting of Si narrows with inspiration (the pulmonic component being delayed) and widens with expiration (paradoxic splitting).

Diagnostic evaluation

Diagnosis may be made on the history and physical findings alone. A cardiac catheterization is necessary to determine the stenotic area, especially in those children with minimal symptoms who are at risk for acute myocardial ischemia. It is also diagnostic in terms of the surgical approach. If a thin membrane is present this is easily removed with excellent results.

Roentgenographic studies may confirm

– left-sided heart enlargement,

– released pulmonary vascularity,

– dilated aorta in the poststenotic area.

Electrocardiogram may show:

-left ventricular hypertrophy or may be normal in mild defects unless taken during a period of exercise.

-Depression of the ST segment indicates myocardial ischemia and is a very important finding in determining the need for surgery.

Echocardiography may show a thick, poorly contractile left ventricular wall and an abnormal aortic valve.

MITRAL STENOSIS

The mitral valve separates the upper and lower chambers on the left side of the heart. Stenosis is a condition in which the valve does not open fully, restricting blood flow. Mitral stenosis is a disorder in which the mitral valve does not open fully.

Causes

Blood that flows between different chambers of your heart must flow through a valve. The valve between the two chambers on the left side of your heart is called the mitral valve. It opens up enough so that blood can flow from the upper chamber of your heart (left atria) to the lower chamber (left ventricle). It then closes, keeping blood from flowing backwards.

Mitral stenosis means that the valve cannot open enough. As a result, less blood flows to the body. The upper heart chamber swells as pressure builds up. Blood and fluid may then collect in the lung tissue (pulmonary edema), making it hard to breathe. See also: heart failure.

In adults, mitral stenosis occurs most often in those who have had rheumatic fever (a condition that may develop after untreated or poorly treated strep throat or scarlet fever). The valve problems develop 5 – 10 years or more after the episode of rheumatic fever, and symptoms may not show up for even longer. Rheumatic fever is becoming rare in the United States due to treatment of strep infections, so mitral stenosis is also less common.

Only rarely do other factors cause mitral stenosis in adults. These include:

Calcium deposits forming around the mitral valve
Radiation treatment to the chest
Some medications

Children may be born with mitral stenosis (congenital) or other birth defects involving the heart that cause mitral stenosis. Often, there are other heart defects present with the mitral stenosis.

Mitral stenosis may run in families.

Symptoms

In adults there may be no symptoms. However, symptoms may appear or get worse with exercise or any activity that raises the heart rate. In adults, symptoms usually develop between ages 20 and 50.

Symptoms may begin with an episode of atrial fibrillation (especially if it causes a fast heart rate). They may also be triggered by pregnancy or other stress on the body, such as infection in the heart or lungs, or other heart disorders.

Symptoms may include:

Chest discomfort (rare)

Increases with activity, decreases with rest
Radiates to the arm, neck, jaw, or other areas
Tight, crushing, pressure, squeezing, constricting

Cough, possibly bloody (hemoptysis)
Difficulty breathing during or after exercise or when lying flat; may wake up with difficulty breathing (most common symptom)
Fatigue, becoming tired easily
Frequent respiratory infections such as bronchitis
Sensation of feeling the heart beat (palpitations)
Swelling of feet or ankles

In infants and children, symptoms may be present from birth (congenital), and almost always develop within the first 2 years of life. Symptoms include:

Cough
Poor feeding or sweating when feeding
Poor growth
Shortness of breath

Exams and Tests

The health care provider will listen to the heart and lungs with a stethoscope. A distinctive murmur, snap, or other abnormal heart sound may be heard. The typical murmur is a rumbling sound that is heard over the heart during the resting phase of the heartbeat. The sound often gets louder just before the heart begins to contract.

The exam may also reveal an irregular heartbeat or lung congestion. Blood pressure is usually normal.

Narrowing or blockage of the valve or swelling of the upper heart chambers may be seen on:

Chest x-ray
CT scan of the heart
Echocardiogram
ECG (electrocardiogram)
MRI of the heart
Transesophageal echocardiogram (TEE)

TRICUSPID STENOSIS

Definition of Tricuspid Valve Disease

Tricuspid Valve Disease can occur when the heart valve between the right atrium and the right ventricle, which normally has three flaps or cusps, becomes narrowed. This lessens the amount of blood flowing into the right ventricle and can reduce the efficiency of the heart.

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Description of Tricuspid Valve Disease

The tricuspid valve is one of four valves that control the flow and direction of blood in and out of the heart. Blood enters the right atrium (upper heart chamber) and passes through the tricuspid valve into the right ventricle (lower pumping chamber) from where it is pumped out through the pulmonary artery in the lungs.

If the valve is narrowed (stenosed), it becomes difficult for a sufficient amount of blood to move through the right heart chambers with each beat. If the valve does not close properly, some blood flowing into the ventricle leaks back into the atrium with each beat. This condition is known as regurgitation or insufficiency. In both cases, the heart must work harder to pump an adequate amount of blood. In tricuspid stenosis, the right atrium becomes enlarged, while the right ventricle does not fill completely and remains small. In tricuspid regurgitation, both right chambers enlarge substantially.

Tricuspid valve disorders, which are rare, often occur in conjunction with other heart valve problems, particularly with mitral valve disorders.

Individuals with tricuspid valve disease are at risk for heart failure and atrial fibrillation (which increases the risk of blood clot formation). As in other types of valve disease, tricuspid disorders also increase the risk of endocarditis

Causes and Risk Factors of Tricuspid Valve Disease

Tricuspid valve stenosis is usually caused by rheumatic heart disease, although it is occasionally due to a congenital condition. Tricuspid valve regurgitation is often secondary to high pressure within the heart’s chambers, usually caused by pulmonary hypertension.

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Symptoms of Tricuspid Valve Disease

Tricuspid regurgitation and stenosis may be present for years without symptoms. When symptoms do occur, they may include an uncomfortable fluttering sensation in the neck or chest because of heart rhythm irregularities. Both conditions can produce the symptoms of right-sided heart failure, including discomfort in the upper abdomen because of an enlarged liver, fatigue and swelling.

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Diagnosis of Tricuspid Valve Disease

Signs of tricuspid valve disease, such as a heart murmur and an abnormal pulse in the jugular vein in the neck, may be detectable during a physical examination.

A chest x-ray, an electrocardiogram (EKG), and an echocardiogram (ultrasound study of the heart muscle and valves) may be helpful in reaching the diagnosis.

Cardiac catheterization may be performed if surgery is being considered.

MITRAL INSUFFICIENCY

Mitral regurgitation (MR), which is also known as mitral insufficiency, is a common heart valve disorder. When mitral regurgitation is present, blood flows backwards through the mitral valve when the heart contracts. This reduces the amount of blood that is pumped out to the body.

This topic review discusses the causes, signs and symptoms, diagnosis, and treatment options for people with mitral regurgitation.

Heart function

Normal heart — The heart is a pump that contains four chambers: the right atrium, right ventricle, left atrium, and left ventricle. Blood returning to the heart flows into the right atrium, and then the right ventricle. Blood is pumped out of the right ventricle into the lungs, where oxygen is added. Blood then returns to the heart through the left atrium. Blood in the left atrium flows into the left ventricle, which pumps the blood to the rest of the body through the aorta.

The heart normally contracts and relaxes in a rhythmic fashion. This action causes changes in pressure within the heart that allow the heart to fill with blood (during relaxation) and to pump blood forward to the body (during contraction).

There are four valves in the heart:

Two valves separate the upper and lower chambers: one on the right (tricuspid valve) and one on the left side of the heart (mitral valve).
Two valves separate the heart from the blood vessels: one is between the heart and the lungs (pulmonic valve) and other is between the heart and the aorta (aortic valve).

These valves consist of flaps called leaflets or cusps that open and close to help ensure the continued forward flow of blood through the heart.

Mitral regurgitation — When mitral regurgitation (MR) is present, blood leaks backwards through the mitral valve and into the left atrium when the heart contracts. This means that less blood is pumped out of the heart to supply the body. If the amount of MR is small and does not progress, the backward leak has no significant consequences.

If significant (moderate to severe) MR is present, the left ventricle must work harder to keep up with the body’s demands for oxygenated blood. Over time, the heart muscle (the myocardium) and circulatory system undergo a series of changes to maintain this increased demand. These changes generally occur in phases over many years, even decades, depending upon the amount of blood that is regurgitated and how the heart responds to the regurgitated blood. The cause of mitral regurgitation also determines how quickly the heart begins to fail.

Compensated phase — The major change during this phase is enlargement of the left ventricle. This is known as the compensated phase, which does not usually cause symptoms, the heart rhythm is usually normal, and surgical treatment is generally not required.

Transitional phase — As mitral regurgitation progresses, the heart muscle (myocardium) begins to weaken, and the ventricle cao longer compensate for the regurgitation. This phase is called the transitional phase. The reason that you might progress from the compensated to the transitional phase is not completely clear, although changes in heart or heart pumping function may occur as progressively greater volumes of blood are regurgitated and/or the size of the left ventricle increases.

You may experience fatigue, have a decreased ability to exercise or be active, or feel short of breath in the transitional phase. However, some people have no symptoms. Surgical treatment is usually recommended when you enter the transitional phase.)

Decompensated phase — As the left ventricle enlarges and functions less efficiently, the left atrium progressively enlarges, abnormal heart rhythms occur, and the blood pressure in the pulmonary artery (the blood vessel from the heart to the lungs) increases; this is called pulmonary hypertension. Over time, these changes become irreversible as the signs and symptoms of heart failure develop..)

Mitral regurgitation causes

A trivial amount of MR is present in up to 70 percent of adults. Significant (moderate to severe) mitral regurgitation is much less common. For example, significant MR was found in only about 2 percent of people in one study. Significant mitral regurgitation can develop as a result of an abnormality in a heart valve or another cardiac disease, including the following:

Mitral valve prolapse — Mitral valve prolapse occurs when the mitral valve leaflet tissue is deformed and elongated so that the leaflets do not come together normally. This abnormal valve motion may allow blood to leak backwards from the left ventricle into the left atrium. Although most people with mitral valve prolapse have only trace or mild MR, some develop significant MR.
Infective endocarditis — Infective endocarditis (IE) is an infection of the heart valves caused by bacteria, fungi, or other organisms that invade the bloodstream. As the microorganisms adhere to the valves and grow, abnormal structures (known as vegetations) develop on the heart valves. The vegetation can prevent the mitral valve from closing normally, allowing blood to regurgitate. A heart valve that is already abnormal is more likely to develop endocarditis compared to a valve that is normal.
Rheumatic fever — Rheumatic fever is a body-wide illness that occurs when the bacterium that causes Strep throat (group A Streptococcus) is not treated. Rheumatic fever causes inflammation of the valves of the heart, as well as other complications. Rheumatic fever is now uncommon in developed countries, although it still occurs commonly in developing countries.
Congenital heart abnormality — Children who are born with certain types of heart abnormalities can develop MR.
Other types of heart disease — MR can develop as a result of other types of heart diseases, such as after a heart attack or other cause of heart muscle injury.
Trauma — Chest trauma can rarely cause breakage of the chords that hold the mitral leaflets in their normal position. Untethered leaflets swing widely, allowing valve leakage.

Mitral regurgitation signs and symptoms

Most people with MR have no symptoms. People with mild to moderate MR may never develop symptoms or serious complications.

Even in people with severe MR, there may be no signs or symptoms until the left ventricle fails, an abnormal heart rhythm develops (atrial fibrillation), or pulmonary hypertension occurs. Pulmonary hypertension occurs when the blood pressure in the pulmonary artery is increased. This increases the workload of the right side of the heart, making it difficult to provide an adequate amount of oxygenated blood to the body.

People with severe MR and left ventricular enlargement may eventually develop signs and symptoms of heart failure, which include weakness and fatigue, shortness of breath with exertion and/or at rest, or edema (abnormal fluid collection in the lower legs or abdomen).

Mitral regurgitation diagnosis

You may be diagnosed with MR after your healthcare provider listens to your heart with a stethoscope and hears a heart murmur. The murmur is caused by the sound of turbulent blood flowing backwards through the mitral valve.

A heart murmur may occur as a result of one or more conditions; to determine the cause of the murmur, one or more diagnostic tests may be recommended.

Electrocardiogram (ECG) — An ECG provides a picture of the electrical activity that causes the heart to beat. An ECG may detect rhythm disturbances or evidence of coronary artery disease or other conditions that can cause MR. It can also show evidence of other associated cardiac abnormalities.

Chest x-ray — A chest x-ray shows the size and shape of the heart and the large blood vessels in the chest. It also can identify fluid accumulation in the lungs. Many people with significant MR have an enlarged heart.

Echocardiogram — An echocardiogram uses ultrasound (high-frequency sound waves) to assess the size of the heart’s chambers, the movement of the heart valves, and the motion of the heart wall. It can also measure the cardiac output (the volume of blood pumped in one minute) and some of the pressures within the heart.

In most cases, the echocardiogram is done by pressing a smooth probe against the skin of the chest or abdomen. Gel is applied to the chest to help the wand glide against the skin and allow the sound waves to travel through the chest more easily. This type of echocardiogram is called a transthoracic echocardiogram.

If the images of the heart are not clear with transthoracic echocardiography, a transesophageal echocardiogram (TEE) may be recommended. With TEE, you are given sedative medication and the probe is inserted into your mouth and passed down the esophagus. This allows the physician to have a closer and clear view of your heart valves and other structures

PULMONARY REGURGITATION (PULMONARY INSUFFICIENCY)

Background:

Over 90 % of the normal population has trivial to mild pulmonary regurgitation (PR) detected by color Doppler echocardiogram. This is what we call physiologic PR and is an incidental finding when the patient is undergoing a color Doppler echocardiogram for other reasons. This type of PR does not need any type of follow-up or intervention, as the pulmonary valve is normal.

There are other cases where the pulmonary valve does not close completely, causing the blood to leak backward from the main pulmonary artery into the right ventricle.

Causes:

As mentioned above, a structurally normal pulmonary valve may have a little amount of PR, which is clinically irrelevant. It is found in most normal hearts.

In some cases, the pulmonary regurgitation is caused by a malformed or thickened pulmonary valve. It may also be seen in patients with pulmonary stenosis who have undergone balloon valvuloplasty. A small subset of patients with complex heart defects may require a pulmonary conduit (tube), which may start leaking as it gets older. It may also be found in some cases of heart surgery for certain types of congenital heart defects. Finally, it may be seen in patients with pulmonary hypertension (high pressure in the lung vessels).

In extremely rare cases, the pulmonary valve may be absent (absent pulmonary valve syndrome). There may be a combination of pulmonary stenosis with severe PR.

Pulmonary regurgitation can be caused by infectious diseases such as endocarditis or by carcinoid heart disease, a very rare condition.

Symptoms:

Most patients with mild to moderate pulmonary valve regurgitation do not experience any symptoms. They may lead a normal life. Patients with a more severe degree of PR may experience some of these symptoms:

Ø Fatigue

Ø Shortness of breath, especially during exertion

Ø Chest pain

Ø Palpitations

Ø Enlarged liver

Ø Fainting with exercise

Ø Exercise intolerance

Symptomatic patients undergo further testing and may require surgical intervention.

Tests:

An echocardiogram (ECHO) is a painless test that uses ultrasound waves to examine the heart. The echocardiogram is a very sensitive test, which will detect any trivial amount of leakage even in a structurally normal pulmonary valve. This is a very common finding in echocardiogram studies and most cardiologists do not mention it as it may cause unnecessary concern to the parents. There are other heart valves that may have a very small amount of leakage that may be physiologic too.

The echocardiogram is very useful detecting the amount of pulmonary regurgitation in cases of “real” leakage. The test also helps to determine the size and function (contractility) of the right ventricle.

Patients with severe pulmonary regurgitation may benefit from an MRI. This study will help determine the need and timing of surgery.

AORTIC INSUFFICIENCY

Background:

Aortic insufficiency is a leakage in the main heart valve, which is called the aortic valve. Aortic regurgitation is another name used for this leakage. The leakage in the aortic valve occurs when there is incomplete coaptation of the valve leaflets (cusps). In other words, when the valve closes up, it does not seal completely and lets some of the blood in the aorta return back into the left ventricle.

A small percentage of the normal population has a trace of aortic insufficiency, undetected by the human ear, and is diagnosed at the time that a patient has a color Doppler echocardiogram. In other words, a normal heart can have a very mild degree of aortic insufficiency and, if the valve is structurally normal, there is no need to worry.

In many cases, the aortic insufficiency is associated with a thickened or deformed aortic valve. This malformed aortic valve may or may not have an obstruction in addition to the leakage.

A bicuspid aortic valve can develop aortic insufficiency. In fact, about one-fourth of patients with a bicuspid aortic valve develop some degree of aortic insufficiency during their lifetime. The leakage is usually mild, but it could become more severe as the child grows.

Causes:

A trace of aortic insufficiency may be associated with a structurally normal aortic valve and may be seen in a small percentage of the normal population. At other times the condition is associated with a congenital defect of the aortic valve. Aortic insufficiency may also be an acquired condition. The causes of aortic valve insufficiency include rheumatic fever, Kawasaki disease, hypertension, endocarditis, and other diseases.

Patients with other types of heart defects and those who have undergone aortic valve surgery may have some degree of leakage in the aortic valve.

Symptoms:

Patients with mild leakage usually lead a normal life and do not experience any symptoms or restrictions. Their quality of life is normal. On the other hand, patients with more severe aortic insufficiency may develop symptoms depending on:

Ø Severity of the leakage.

Ø Whether it is acute or a chronic condition.

Ø If there is associated heart defects or heart failure.

Ø If the valve has an active infection (endocarditis).

Symptoms may include:

Ø Shortness of breath, especially during exercise.

Ø Chest pain.

Ø Fluttering (palpitations).

Ø Poor exercise tolerance.

Ø Rapid heartbeats.

Ø Fatigue.

Ø Problems with weight.

Ø Bounding pulses.

Ø Changes in blood pressure.

Ø Heart failure.

Tests and Treatment:

Cardiovascular testing usually includes an electrocardiogram and echocardiogram. In cases of trace to mild aortic insufficiency, there may not be need of any further testing, just periodic follow up by Dr. Villafañe. A chest x-ray usually is obtained in cases of moderate to severe leakage of the aortic valve. A stress test may be indicated in order to determine exercise performance and evaluation of any symptoms that may be linked to the aortic insufficiency.

TRICUSPID INSUFFICIENCY

Background:

Mild Tricuspid regurgitation may be detected in over 90% of the normal population by color Doppler echocardiogram. This is usually a benign finding and does not require any follow up or treatment. Virtually all of the normal population will have a mild degree of leakage in one, two, or three of the heart valves by echocardiogram. We call this physiologic regurgitation and many cardiologists prefer not to mention it to parents, as they may become concerned about a common and benign echocardiogram finding.

Pathologic tricuspid regurgitation is a disorder involving backward flow of blood across the tricuspid valve from the right ventricle (lower heart chamber) to the right atrium (upper heart chamber). Leakage occurs during contraction of the right ventricle and may be caused by damage or malformation of the tricuspid valve or and/or by significant enlargement of the right heart. The tricuspid valve may have been damaged by infection (endocarditis). In other cases, it may be a congenital malformation in the valve itself such as a dysplastic pulmonary valve or Ebstein’s anomaly of the tricuspid valve.

Tricuspid regurgitation may also be present in cases of distal anatomic obstructions such as pulmonary valve atresia or in cases of pulmonary hypertension (high pressures in the lungs). Rarely it may be caused by an unusual tumor called a carcinoid, rheumatoid arthritis, radiation therapy, Marfan’s syndrome, or chest trauma. Finally, tricuspid regurgitation is found in many patients with a single ventricle, corrected transposition of the great arteries or those who underwent the Fontan procedure in which the right ventricle is acting as the main pump of the heart. Those patients require lifetime follow up with serial echocardiograms. The tricuspid regurgitation may become severe enough to require heart surgery.

Other potential causes of significant tricuspid regurgitation include restrictive cardiomyopathy and constrictive pericarditis.

Symptoms:

Mild to moderate tricuspid regurgitation may not produce any symptoms at all in patients with normal pulmonary pressures. Patients with pulmonary hypertension and/or severe tricuspid regurgitation may experience these symptoms:

Ø Fatigue, tiredness

Ø Weakness

Ø Difficulty breathing

Ø Shortness of breath, especially on exertion

Ø General swelling

Ø Swelling of the abdomen

Ø Swelling of the feet and ankles

Ø Active pulsing in the neck veins

Ø Palpitations or “racing heart”

Ø Weight loss

Ø Loss of appetite

Ø Heart failure

Diagnosis and Cardiovascular Tests:

In cases of mild tricuspid regurgitation, the physical examination may be completely normal without an audible heart murmur. In cases of moderate severe tricuspid regurgitation, a heart murmur may be present and the liver may be enlarged. The abdomen may be distended and edema (swollen extremities) may be present. The electrocardiogram and chest x-ray may be abnormal. The echocardiogram is very helpful in determining the degree of tricuspid regurgitation, the size of the right heart, and its function. In addition, it may show the veins draining into the heart as being dilated. An echo may show any malformation or damage to the tricuspid valve or if an associated heart defect is present. Doppler echocardiography is used to estimate the pressures inside the heart and lungs. In more severe cases, the patient may require an MRI or cardiac catheterization.

Treatment:

Most patients with mild tricuspid regurgitation will not require any medical treatment. Patients with a normal heart and very mild forms of tricuspid regurgitation do not require any follow up. In more severe cases, the patients may require diuretics (water pills), while other patients may benefit from other medications that help improve the contractility of the heart. Medical treatment may depend on the underlying condition. For example, patients with pulmonary hypertension may require specific medications to lower lung pressures.

In general, patients with a single ventricle and the Fontan procedure may be on a few medications that may help release some of the volume overload or workload of the right ventricle and others may help improve the contractility of the heart pump.

Patients with an anatomical or structural problem of the tricuspid valve may require heart surgery. Some patients with progressive tricuspid regurgitation may also require surgery to prevent further deterioration of heart function.

COARCTATION OF AORTA

Coarctation of the aorta is a congenital (present at birth) heart defect involving a narrowing of the aorta. The aorta is the large artery that carries oxygen-rich (red) blood from the left ventricle to the body. It is shaped like a candy cane, with the first section moving up towards the head (ascending aorta), then curving in a C-shape as smaller arteries that are attached to it carry blood to the head and arms (aortic arch). After the curve, the aorta becomes straight again, and moves downward towards the abdomen, carrying blood to the lower part of the body (descending aorta).

The narrowed segment called coarctation can occur anywhere in the aorta, but is most likely to happen in the segment just after the aortic arch. This narrowing restricts the amount of oxygen-rich (red) blood that can travel to the lower part of the body. Varying degrees of narrowing can occur.

The more severe the narrowing, the more symptomatic a child will be, and the earlier the problem will be noticed. In some cases, coarctation is noted in infancy. In others, however, it may not be noted until school-age or adolescence.

Seventy-five percent of children with coarctation of the aorta also have a bicuspid aortic valve – a valve that has two leaflets instead of the usual three.

Coarctation of the aorta occurs in about 8 percent to 11 percent of all children with congenital heart disease. Boys have the defect twice as often as girls do.

What causes coarctation of the aorta?

Some congenital heart defects may have a genetic link, either occurring due to a defect in a gene, a chromosome abnormality, or environmental exposure, causing heart problems to occur more often in certain families. Most of the time this heart defect occurs sporadically (by chance), with no clear reason for its development.

Why is coarctation a concern?

Coarctation of the aorta causes several problems, including the following:

The left ventricle has to work harder to try to move blood through the narrowing in the aorta. Eventually, the left ventricle is no longer able to handle the extra workload, and it fails to pump blood to the body efficiently.
Blood pressure is higher above the narrowing, and lower below the narrowing. Older children may have headaches from too much pressure in the vessels in the head, or cramps in the legs or abdomen from too little blood flow in that region. Also, the kidneys may not make enough urine since they require a certain amount of blood flow and a certain blood pressure to perform this task.
The walls of the ascending aorta, the aortic arch, or any of the arteries in the head and arms may become weakened by high pressure. Spontaneous tears in any of these arteries can occur, which can cause a stroke or uncontrollable bleeding.
There is a higher than average chance of developing an infection in the valves of the heart knows as bacterial endocarditis or an infection in the aorta itself known as bacterial endarteritis. Both of these complications are exceedingly rare.
The coronary arteries, which supply oxygen-rich (red) blood to the heart muscle, may narrow in response to elevated pressure.

What are the symptoms of coarctation of the aorta?

Symptoms noted in early infancy are caused by moderate to severe aortic narrowing. The following are the most common symptoms of coarctation of the aorta. However, each child may experience symptoms differently. Symptoms may include:

irritability
pale skin
sweating
heavy and/or rapid breathing
poor feeding
poor weight gain
cold legs and feet
diminished or absent pulses in the legs and feet
blood pressure in the arms, particularly the right arm, significantly greater than the blood pressure in the legs

Mild narrowing may not cause symptoms at all. Often, a school-aged child or adolescent is simply noted to have high blood pressure or a heart murmur on a physical examination. Some may complain of headaches or cramps in the lower sections of the body.

The symptoms of coarctation of the aorta may resemble other medical conditions or heart problems. Always consult your child’s physician for a diagnosis.

How is coarctation of the aorta diagnosed?

Your child’s physician may have heard a heart murmur during a physical examination, and referred your child to a pediatric cardiologist for a diagnosis. A heart murmur is simply a noise caused by the turbulence of blood flowing through the obstruction. Symptoms your child exhibits will also help with the diagnosis.

A pediatric cardiologist specializes in the diagnosis and medical management of congenital heart defects, as well as heart problems that may develop later in childhood. The cardiologist will perform a physical examination, listening to your child’s heart and lungs, and make other observations that help in the diagnosis. The location within the chest that the murmur is heard best, as well as the loudness and quality of the murmur (harsh, blowing, etc.) will give the cardiologist an initial idea of which heart problem your child may have.

Diagnostic testing for congenital heart disease varies by the child’s age, clinical condition, and institutional preferences. Some tests that may be recommended include the following:

chest x-ray – diagnostic test which uses invisible X-ray energy beams to produce images of internal tissues, bones, and organs onto film.
electrocardiogram (ECG or EKG) – a test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle damage.
echocardiogram (echo) – a procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor that produce a moving picture of the heart and heart valves. The vast majority of aortic coarctations are diagnosed by echocardiography.
cardiac catheterization (cath) – a diagnostic procedure that uses threading a catheter through the arteries and veins of the groin and advancing this catheter up to the heart. Dye is squirted into the heart and aorta and pictures are taken of the anatomy. Catheterization may also be used to repair the coarctation if the child is big enough.
magnetic resonance imaging (MRI) – a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body.

Treatment for coarctation of the aorta:

Specific treatment for coarctation of the aorta will be determined by your child’s physician based on:

your child’s age, overall health, and medical history
extent of the disease
your child’s tolerance for specific medications, procedures, or therapies
expectations for the course of the defect
your opinion or preference

Coarctation of the aorta is treated with repair of the narrowed vessel. Several options are currently available.

surgical repair
Your child’s coarctation of the aorta may be repaired surgically in an operating room. The surgical repair is performed under general anesthesia. The narrowed area is either surgically removed, or made larger with the help of surrounding structures or a patch.
interventional cardiac catheterization
The cardiac catheterization procedure may also be an option for treatment, usually for older children and teenagers. During the procedure, the child is sedated and a small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin and guided to the inside of the heart. Once the catheter is in the heart, the cardiologist will pass an inflated balloon through the narrowed section of the aorta to stretch the area open. A small device, called a stent, may also be placed in the narrowed area after the balloon dilation to keep the aorta open. Overnight observation in the hospital is generally required.

Young infants may be very sick, requiring care in the intensive care unit (ICU) prior to the procedure, and could possibly eveeed emergency repair of the coarctation. Others, who are exhibiting few symptoms, will have the repair scheduled on a less urgent basis.

After surgery, children will return to the intensive care unit (ICU) to be closely monitored during recovery.

While your child is in the ICU, special equipment will be used to help him/her recover, and may include the following:

ventilator – a machine that helps your child breathe while he/she is under anesthesia during the operation. A small, plastic tube is guided into the windpipe and attached to the ventilator, which breathes for your child while he/she is too sleepy to breathe effectively on his/her own. Many children remain on the ventilator for a while after surgery so they can rest.
intravenous (IV) catheters – small, plastic tubes inserted through the skin into blood vessels to provide IV fluids and important medicines that help your child recover from the operation.
arterial line – a specialized IV placed in the wrist, or other area of the body where a pulse can be felt, that measures blood pressure continuously during surgery and while your child is in the ICU.
nasogastric (NG) tube – a small, flexible tube that keeps the stomach drained of acid and gas bubbles that may build up during surgery.
urinary catheter – a small, flexible tube that allows urine to drain out of the bladder and accurately measures how much urine the body makes, which helps determine how well the heart is functioning. After surgery, the heart will be a little weaker than it was before, and, therefore, the body may start to hold onto fluid, causing swelling and puffiness. Diuretics may be given to help the kidneys to remove excess fluid from the body.
chest tube – a drainage tube will be inserted to keep the chest free of blood that would otherwise accumulate after the incision is closed. Bleeding may occur for several hours, or even a few days after surgery.
heart monitor – a machine that constantly displays a picture of your child’s heart rhythm, and monitors heart rate, arterial blood pressure, and other values.

Your child may need other equipment not mentioned here to provide support while in the ICU, or afterwards. The hospital staff will explain all of the necessary equipment to you.

Your child will be kept as comfortable as possible with several different medications; some which relieve pain, and some which relieve anxiety. The staff will also be asking for your input as to how best to soothe and comfort your child.

After discharged from the ICU, your child will recuperate on another hospital unit for a few days before going home. You will learn how to care for your child at home before your child is discharged. Your child may need to take medications for a while, and these will be explained to you. The staff will give you instructions regarding medications, activity limitations, and follow-up appointments before your child is discharged.

Long-term outlook after coarctation of the aorta surgical repair:

Most children who have had a coarctation of the aorta surgical repair will live healthy lives. Activity levels, appetite, and growth should eventually return to normal.

Your child’s cardiologist may recommend that antibiotics be given to prevent bacterial endocarditis before major surgeries or procedures, such as dental cleaning.

As the child grows, the aorta may once again become narrowed. If this happens, a balloon procedure or operation may be necessary to repair the coarctation. Evaluation with magnetic resonance imaging (MRI) is generally recommended. If an aortic aneurysm or dissection is suspected, computed tomography (CT scan) may also be performed to evaluate the anatomy further before deciding on treatment options.

Blood pressure management is very important. Often, the blood pressure in the child is elevated after aortic coarctation repair. In that case, medications may be prescribed to help lower the child’s blood pressure.

Regular follow-up care at a center offering pediatric or adult congenital cardiac care should continue throughout the individual’s lifespan.

VENTRICULAR SEPTAL DEFECT

A ventricular septal defect is an opening in the ventricular septum, or dividing wall between the two lower chambers of the heart known as the right and left ventricles. VSD is a congenital (present at birth) heart defect. As the fetus is growing, something occurs to affect heart development during the first 8 weeks of pregnancy, resulting in a VSD.

Normally, oxygen-poor (blue) blood returns to the right atrium from the body, travels to the right ventricle, then is pumped into the lungs where it receives oxygen. Oxygen-rich (red) blood returns to the left atrium from the lungs, passes into the left ventricle, and then is pumped out to the body through the aorta.

A ventricular septal defect allows oxygen-rich (red) blood to pass from the left ventricle, through the opening in the septum, and then mix with oxygen-poor (blue) blood in the right ventricle.

What are the different types of VSD?

There are four basic types of VSD:

perimembranous VSD – an opening in a particular area of the upper section of the ventricular septum (an area called the membranous septum), near the valves. This type of VSD is the most commonly operated upon since most perimembranous VSDs do not spontaneously close.
muscular VSD – an opening in the muscular portion of the lower section of the ventricular septum. This is the most common type of VSD. A large number of these muscular VSDs close spontaneously and do not require congenital heart surgery.
atrioventricular canal type VSD – a VSD associated with atrioventricular canal defect. The VSD is located underneath the tricuspid and mitral valves.
conal septal VSD – the rarest of VSDs which occur in the ventricular septum just below the pulmonary valve.

Ventricular septal defects are the most commonly occurring type of congenital heart defect, accounting for 25 percent of congenital heart disease cases.

What causes ventricular septal defect?

The heart is forming during the first 8 weeks of fetal development. It begins as a hollow tube, then partitions within the tube develop that eventually become the septa (or walls) dividing the right side of the heart from the left. Ventricular septal defects occur when the partitioning process does not occur completely, leaving an opening in the ventricular septum.

Some congenital heart defects may have a genetic link, either occurring due to a defect in a gene, a chromosome abnormality, or environmental exposure, causing heart problems to occur more often in certain families. Most ventricular septal defects occur sporadically (by chance), with no clear reason for their development.

Why is ventricular septal defect a concern?

If not treated, this heart defect can cause lung disease. When blood passes through the VSD from the left ventricle to the right ventricle, a larger volume of blood thaormal must be handled by the right side of the heart. Extra blood then passes through the pulmonary artery into the lungs, causing higher pressure thaormal in the blood vessels in the lungs.

A small opening in the ventricular septum allows a small amount of blood to pass through from the left ventricle to the right ventricle. A large opening allows more blood to pass through and mix with the normal blood flow in the right heart. Extra blood causes higher pressure in the blood vessels in the lungs. The larger the volume of blood that goes to the lungs, the higher the pressure.

The lungs are able to cope with this extra pressure for while, depending on exactly how high the pressure is. After a while, however, the blood vessels in the lungs become diseased by the extra pressure.

As pressure builds up in the lungs, the flow of blood from the left ventricle, through the VSD, into the right ventricle, and on to the lungs will diminish. This helps preserve the function of the lungs, but causes yet another problem. Blood flow within the heart goes from areas where the pressure is high to areas where the pressure is low. If a ventricular septal defect is not repaired, and lung disease begins to occur, pressure in the right side of the heart will eventually exceed pressure in the left. In this instance, it will be easier for oxygen-poor (blue) blood to flow from the right ventricle, through the VSD, into the left ventricle, and on to the body. When this happens, the body does not receive enough oxygen in the bloodstream to meet its needs.

Because blood is pumped at high pressure by the left ventricle through the VSD, tissue damage may eventually occur in the right ventricle. Bacteria in the bloodstream can easily infect this injured area, causing a serious illness known as bacterial endocarditis.

Some ventricular septal defects are found in combination with other heart defects (such as in transposition of the great arteries).

What are the symptoms of a ventricular septal defect?

The size of the ventricular septal opening will affect the type of symptoms noted, the severity of symptoms, and the age at which they first occur. A VSD permits extra blood to pass from the left ventricle through to the right side of the heart, and the right ventricle and lungs become overworked as a result. The larger the opening, the greater the amount of blood that passes through and overloads the right ventricle and lungs.

Symptoms often occur in infancy. The following are the most common symptoms of VSD. However, each child may experience symptoms differently. Symptoms may include:

fatigue
sweating
rapid breathing
heavy breathing
congested breathing
disinterest in feeding, or tiring while feeding
poor weight gain

The symptoms of VSD may resemble other medical conditions or heart problems. Always consult your child’s physician for a diagnosis.

How is a ventricular septal defect diagnosed?

Your child’s physician may have heard a heart murmur during a physical examination, and referred your child to a pediatric cardiologist for a diagnosis. A heart murmur is simply a noise caused by the turbulence of blood flowing through the opening from the left side of the heart to the right.

A pediatric cardiologist specializes in the diagnosis and medical management of congenital heart defects, as well as heart problems that may develop later in childhood. The cardiologist will perform a physical examination, listening to the heart and lungs, and make other observations that help in the diagnosis. The location within the chest where the murmur is heard best, as well as the loudness and quality of the murmur (harsh, blowing, etc.) will give the cardiologist an initial idea of which heart problem your child may have. Diagnostic testing for congenital heart disease varies by the child’s age, clinical condition, and institutional preferences. Some tests that may be recommended include the following:

chest x-ray – a diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film. With a VSD, the heart may be enlarged because the right ventricle handles larger amounts of blood flow thaormal. Also, there may be changes that take place in the lungs due to extra blood flow that can be seen on an x-ray.
electrocardiogram (ECG or EKG) – a test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle stress.
echocardiogram (echo) – a procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor that produce a moving picture of the heart and heart valves. An echo can show the pattern of blood flow through the septal opening, and determine how large the opening is, as well as much blood is passing through it.
cardiac catheterization – a cardiac catheterization is an invasive procedure that gives very detailed information about the structures inside the heart. Under sedation, a small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin, and guided to the inside of the heart. Blood pressure and oxygen measurements are taken in the four chambers of the heart, as well as the pulmonary artery and aorta. Contrast dye is also injected to more clearly visualize the structures inside the heart.

Treatment for ventricular septal defect:

Specific treatment for VSD will be determined by your child’s physician based on:

your child’s age, overall health, and medical history
extent of the disease
your child’s tolerance for specific medications, procedures, or therapies
expectations for the course of the disease
your opinion or preference

Small ventricular septal defects may close spontaneously as your child grows. A larger VSD usually requires surgical repair. Regardless of the type, once a ventricular septal defect is diagnosed, your child’s cardiologist will evaluate your child periodically to see whether it is closing on its own. A VSD will be repaired if it has not closed on its own – to prevent lung problems that will develop from long-time exposure to extra blood flow.

Treatment may include:

medical management
Some children have no symptoms, and require no medication. However, many children may need to take medications to help the heart work more efficiently, due to the strain from the extra blood passing through the VSD. Medications that may be prescribed include the following:

digoxin – a medication that helps strengthen the heart muscle, enabling it to pump more efficiently.
diuretics – the body’s water balance can be affected when the heart is not working as well as it could. These medications help the kidneys remove excess fluid from the lungs and the body.
ACE inhibitors – medications that lower the blood pressue in the body, making it easier for the blood to be pumped from the left ventricle into the body (because of its lowered blood pressure) rather than that blood being pumped from the left ventricle across the VSD into the right ventricle then into the lungs.

adequate nutrition
Infants with a larger VSD may become tired when feeding, and are not able to eat enough to gain weight. Options that can be used to ensure your baby will have adequate nutrition include the following:

high-calorie formula or breast milk
Special nutritional supplements may be added to formula or pumped breast milk that increase the number of calories in each ounce, thereby allowing your baby to drink less and still consume enough calories to grow properly.
supplemental tube feedings
Feedings given through a small, flexible tube that passes through the nose, down the esophagus, and into the stomach, can either supplement or take the place of bottle feedings. Infants who can drink part of their bottle, but not all, may be fed the remainder through the feeding tube. Infants who are too tired to bottle feed may receive their formula or breast milk through the feeding tube alone.

infection control
Children with certain heart defects are at risk for developing an infection of the inner surfaces of the heart known as bacterial endocarditis. A common procedure that puts your child at risk for this infection is a routine dental check-up and teeth cleaning. Other procedures may also increase the risk of the heart infection occurring. However, giving children with heart defects an antibiotic by mouth before these procedures can help prevent bacterial endocarditis. It is important that you inform all medical personnel that your child has a VSD so they may determine if the antibiotics are necessary before a procedure.
surgical repair
Surgical repair of VSD is indicated for defects that are causing symptoms, such as poor weight gain and rapid breathing. Your child’s cardiologist will recommend when the repair should be performed based on echocardiogram. The operation is performed under general anesthesia. Depending on the size of the heart defect and your physician’s recommendations, the ventricular septal defect will be closed with stitches or a special patch. Consult your child’s cardiologist for more information.
interventional cardiac catheterization
Some types of VSDs may be repaired by a cardiac catheterization procedure. Large muscular defects deep in heart muscle are often difficult to close with surgery. One method currently being used to close some muscular VSDs is the use of a device called a septal occluder. During this procedure, the child is sedated and a small, thin flexible tube is inserted into a blood vessel in the groin and guided into the heart. Once the catheter is in the heart, the cardiologist will pass the septal occluder into the VSD. The septal occluder closes the ventricular septal defect providing a permanent seal.

ATRIAL SEPTAL DEFECT

An atrial septal defect is an opening in the atrial septum, or dividing wall between the two upper chambers of the heart known as the right and left atria. ASD is a congenital (present at birth) heart defect. As the fetus is growing, something occurs to affect heart development during the first eight weeks of pregnancy, resulting in an ASD.

An atrial septal defect allows oxygen-rich (red) blood to pass from the left atrium, through the opening in the septum, and then mix with oxygen-poor (blue) blood in the right atrium.

Atrial septal defects occur in 6 percent to 8 percent of all children born with congenital heart disease. For unknown reasons, girls have atrial septal defects twice as often as boys.

What causes an atrial septal defect?

The heart is forming during the first eight weeks of fetal development. It begins as a hollow tube, then partitions within the tube develop that eventually become the septa (or walls) dividing the right side of the heart from the left. Atrial septal defects occur when the partitioning process does not occur completely, leaving an opening in the atrial septum.

Some congenital heart defects may have a genetic link, either occurring due to a defect in a gene, a chromosome abnormality, or environmental exposure, causing heart problems to occur more often in certain families. Most atrial septal defects occur sporadically (by chance), with no clear reason for their development.

What are the types of atrial septal defects?

There are four types of atrial septal defects:

ostium secundum atrial septal defect
This is the most common atrial septal defect, affecting 80 percent of people with atrial septal defects. It is caused when a part of the atrial septum fails to close completely while the heart is developing. This causes an opening to develop in the center of the wall separating the two atria.
ostium primum atrial septal defect
This defect is part of the atrioventricular canal defects, and is associated with a split (cleft) in one of the leaflets of the mitral valve.
sinus venosus atrial septal defect
This defect occurs at the superior vena cava and right atrium junction, in the area where the pulmonary veins enter the heart. As a result, the drainage of one or more of the pulmonary veins may be abnormal in that the pulmonary veins enter the right atrium rather than the left atrium.
coronary sinus atrial septal defect
This defect is located within the coronary sinus, which is the structure in the right atrium where all the heart’s own veins drain into the right atrium. It is the rarest of all atrial septal defects.

Why is an atrial septal defect a concern?

This heart defect can over time cause lung problems if not repaired. When blood passes through the ASD from the left atrium to the right atrium, a larger volume of blood thaormal must be handled by the right side of the heart. This extra blood passes through the pulmonary artery into the lungs, causing higher amounts of blood flow thaormal in the vessels in the lungs.

A small opening in the atrial septum allows a small amount of blood to pass through from the left atrium to the right atrium. A large opening allows more blood to pass through and mix with the normal blood flow in the right heart..

The lungs are able to cope with this blood flow for a long period of time. In some patients, the extra blood flow eventually raises the blood pressure in the lungs, usually after several decades. This then hardens the blood vessels in the lungs, causing them to be diseased, resulting in irreversible changes in the lungs.

What are the symptoms of an atrial septal defect?

Many children have no symptoms and seem healthy. However, if the ASD is large, permitting a large amount of blood to pass through to the right side of the heart, the right atrium, right ventricle, and lungs will become overworked, and symptoms may be noted. The following are the most common symptoms of atrial septal defect. However, each child may experience symptoms differently. Symptoms may include:

child tires easily when playing
fatigue
sweating
rapid breathing
shortness of breath
poor growth
frequent respiratory infections

The symptoms of an atrial septal defect may resemble other medical conditions or heart problems. Always consult your child’s physician for a diagnosis.

How is an atrial septal defect diagnosed?

Your child’s physician may have heard a heart murmur during a physical examination, and referred your child to a pediatric cardiologist for a diagnosis. A heart murmur is simply a noise caused by the turbulence of blood flowing through the opening from the left side of the heart to the right.

A pediatric cardiologist specializes in the diagnosis and medical management of congenital heart defects, as well as heart problems that may develop later in childhood. The cardiologist will perform a physical examination, listening to the heart and lungs, and make other observations that help in the diagnosis. The location within the chest that the murmur is heard best, as well as the loudness and quality of the murmur (harsh, blowing, etc.) will give the cardiologist an initial idea of which heart problem your child may have. Diagnostic testing for congenital heart disease varies by the child’s age, clinical condition, and institutional preferences. Some tests that may be recommended include the following:

chest X-ray – a diagnostic test which uses invisible X-ray beams to produce images of internal tissues, bones, and organs onto film. With an ASD, the heart may be enlarged because the right atrium and ventricle have to handle larger amounts of blood flow thaormal. Also, there may be changes that take place in the lungs due to extra blood flow that can be seen on an X-ray.
electrocardiogram (ECG or EKG) – a test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle stress.
echocardiogram (echo) – a procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor that produce a moving picture of the heart and heart valves. An echo can show the pattern of blood flow through the atrial septal opening, and determine how large the opening is, as well as how much blood is passing through it.
cardiac catheterization – a cardiac catheterization is an invasive procedure that gives very detailed information about the structures inside the heart. Under sedation, a small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin, and guided to the inside of the heart. Blood pressure and oxygen measurements are taken in the four chambers of the heart, as well as the pulmonary artery and aorta. Contrast dye is also injected to more clearly visualize the structures inside the heart. Although an echocardiogram often provides enough diagnostic information, device closure of the ASD can be performed at the time of the catheterization.

Treatment for atrial septal defect:

Specific treatment for ASD will be determined by your child’s physician based on:

your child’s age, overall health, and medical history
extent of the disease
your child’s tolerance for specific medications, procedures, or therapies
expectations for the course of the disease
your opinion or preference

Secundum atrial septal defects may close spontaneously as a child grows. Once an atrial septal defect is diagnosed, your child’s cardiologist will evaluate your child periodically to see whether it is closing on its own. Usually, an ASD will be repaired if it has not closed on its own by the time your child starts school – to prevent lung problems that will develop from long-time exposure to extra blood flow. The decision to close the ASD may also depend on the size of the defect. Individuals who have their atrial septal defects repaired in childhood can prevent problems later in life.

Treatment may include:

medical management
Many children have no symptoms, and require no medications. However, some children may need to take medications to help the heart work better, since the right side is under strain from the extra blood passing through the ASD. Medications that may be prescribed include the following:

digoxin – a medication that helps strengthen the heart muscle, enabling it to pump more efficiently.
diuretics – the body’s water balance can be affected when the heart is not working as well as it could. These medications help the kidneys remove excess fluid from the body.

infection control
Children with certain heart defects are at risk for developing an infection of the inner surfaces of the heart known as bacterial endocarditis. It is important that you inform all medical personnel that your child has an ASD so they may determine if the antibiotics are necessary before a procedure.
surgical repair
Your child’s ASD may be repaired surgically in the operating room. The surgical repair is performed under general anesthesia. The defect may be closed with stitches or a special patch.
device closure
Device closure is frequently performed for secundum ASD, depending on the size of the defect and the weight of the child. During the cardiac catheterization procedure, the child is sedated and a small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin and guided to the inside of the heart. Once the catheter is in the heart, the cardiologist will pass a special device, called a septal occluder, into the open ASD, preventing blood from flowing through it.

TETRALOGY OF FALLOT

Tetralogy of Fallot (TOF or “TET”) is a complex condition of several congenital (present at birth) defects that occur due to abnormal development of the fetal heart during the first 8 weeks of pregnancy. These problems include the following:

ventricular septal defect (VSD) – an opening in the ventricular septum, or dividing wall between the two lower chambers of the heart known as the right and left ventricles.
pulmonary (or right ventricular outflow tract) obstruction – a muscular obstruction in the right ventricle, just below the pulmonary valve, that decreases the normal flow of blood. The pulmonary valve may also be small.
overriding aorta – the aorta is shifted towards the right side of the heart so that it sits over the ventricular septal defect.

“Tetralogy” refers to four heart problems. The fourth problem is that the right ventricle becomes enlarged as it tries to pump blood past the obstruction into the pulmonary artery.

Normally, oxygen-poor (blue) blood returns to the right atrium from the body, travels to the right ventricle, then is pumped through the pulmonary artery into the lungs where it receives oxygen. Oxygen-rich (red) blood returns to the left atrium from the lungs, passes into the left ventricle, and then is pumped through the aorta out to the body.

In tetralogy of Fallot, blood flow within the heart varies, and is largely dependent on the size of the ventricular septal defect, and how severe the obstruction in the right ventricle is.

With mild right ventricle obstruction, the pressure in the right ventricle can be slightly higher than the left. Some of the oxygen-poor (blue) blood in the right ventricle will pass through the VSD to the left ventricle, mix with the oxygen-rich (red) blood there, and then flow into the aorta. The rest of the oxygen-poor (blue) blood will go its normal route to the lungs. These children may have slightly lower oxygen levels than usual, but may not appear blue.
With more serious obstruction in the right ventricle, it is harder for oxygen-poor (blue) blood to flow into the pulmonary artery, so more of it passes through the VSD into the left ventricle, mixing with oxygen-rich (red) blood, and then moving on out to the body. These children will have lower thaormal oxygen levels in the bloodstream, and may appear blue, especially whenever the pressure in the right ventricle is very high and large amounts of oxygen-poor (blue) blood passes through the VSD to the left side of the heart.

Tetralogy of Fallot makes up about 5 to 7 percent of all cases of congenital heart defects and occurs equally in boys and in girls.

What causes tetralogy of Fallot?

Maternal abuse of alcohol during pregnancy, leading to fetal alcohol syndrome (FAS), is linked to tetralogy of Fallot. Mothers who take medications to control seizures and mothers with phenylketonuria (PKU) are also more likely to have a baby with tetralogy of Fallot.

Most of the time, this heart defect occurs sporadically (by chance), with no clear reason evident for its development.

Why is tetralogy of Fallot a concern?

The amount of oxygen-poor (blue) blood that passes through the VSD to the left side of the heart varies. If the right ventricle obstruction is severe, or if the pressure in the lungs is high, a large amount of oxygen-poor (blue) blood passes through the VSD, mixes with the oxygen-rich (red) blood in the left ventricle, and is pumped to the body. The more blood that goes through the VSD, the less blood that goes through the pulmonary artery to the lungs, and the less oxygen-rich (red) blood that returns to the right side of the heart. Soon, nearly all the blood in the left ventricle is oxygen-poor (blue). This is an emergency situation, as the body will not have enough oxygen to meet its needs.

Some situations, such as crying, increase the pressure in the lungs temporarily, and increasing blueness might be noted as a baby with tetralogy of Fallot cries. In other situations, the pathway from the right ventricle to the pulmonary artery becomes tighter, preventing much blood from passing that way, and allowing oxygen-poor (blue) blood to flow through the VSD into the left heart circulation. Both of these situations are nicknamed “TET spells.” Sometimes, steps can be taken to lessen the pressure or the obstruction, and allow more blood to flow into the lungs and less through the VSD. These steps, however, are not always effective.

What are the symptoms of tetralogy of Fallot?

The following are the most common symptoms of tetralogy of Fallot. However, each child may experience symptoms differently. Symptoms may include:

Because large amounts of oxygen-poor (blue) blood can flow to the body under certain circumstances, one of the indications of tetralogy of Fallot is blueness (blue color of the skin, lips, and nail beds) that occurs with such activity as crying or feeding, and quickly becomes more obvious.
Some babies do not have noticeable cyanosis (blue color of the skin, lips, and nailbeds), but may instead be very irritable or lethargic due to a decreasing amount of oxygen available in the bloodstream.
Some children become pale or ashen in color, and may have cool, clammy skin.

Any of these can be symptoms of tetralogy of Fallot. The symptoms of tetralogy of Fallot may resemble other medical conditions or heart problems. Always consult your child’s physician for a diagnosis.

How is tetralogy of Fallot diagnosed?

Your child’s physician may have heard a heart murmur during a physical examination, and referred your child to a pediatric cardiologist for a diagnosis. A heart murmur is simply a noise caused by the turbulence of blood flowing through the obstruction from the right ventricle to the pulmonary artery. Symptoms your child exhibits will also help with the diagnosis.

A pediatric cardiologist specializes in the diagnosis and medical management of congenital heart defects, as well as heart problems that may develop later in childhood. The cardiologist will perform a physical examination, listening to the heart and lungs, and make other observations that help in the diagnosis. The location within the chest that the murmur is heard best, as well as the loudness and quality of the murmur (harsh, blowing, etc.) will give the cardiologist an initial idea of which heart problem your child may have. Diagnostic testing for congenital heart disease varies by the child’s age, clinical condition, and institutional preferences. Some tests that may be recommended include the following:

chest x-ray – a diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.
electrocardiogram (ECG or EKG) – a test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle stress.
echocardiogram (echo) – a procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor that produce a moving picture of the heart and heart valves.
cardiac catheterization – a cardiac catheterization is an invasive procedure that gives very detailed information about the structures inside the heart. Under sedation, a small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin, and guided to the inside of the heart. Blood pressure and oxygen measurements are taken in the four chambers of the heart, as well as the pulmonary artery and aorta. Contrast dye is also injected to more clearly visualize the structures inside the heart.

Treatment for tetralogy of Fallot treated:

Specific treatment for tetralogy of Fallot will be determined by your child’s physician based on:

your child’s age, overall health, and medical history
extent of the condition
your child’s tolerance for specific medications, procedures, or therapies
expectations for the course of the condition
your opinion or preference

Tetralogy of Fallot is treated by surgical repair of the defects. A team of cardiac surgeons performs the surgery, usually before an infant is 1 year old. In many cases, the repair is made at around 6 months of age, or even a little earlier. Repairing the heart defects will allow oxygen-poor (blue) blood to travel its normal route through the pulmonary artery to receive oxygen.

The operation is performed under general anesthesia, and involves the following:

The ventricular septal defect is closed with a patch.
The obstructed pathway between the right ventricle and the pulmonary artery is opened and enlarged with a patch. If the pulmonary valve is small, it may be opened as well or partially or entirely removed.

HYPOXEMIA IN THE INFANT

• below 95% pulse oximetry.

• cyanosis results from hypoxemia

• perioral cyanosis indicates central hypoxemia

• acrocyanosis does not.

Response to Hypoxemia

• acute: HR increases

• chronic: bone marrow produces more RBC to increase the amount of Hgb available for oxygen transport.

• Hct>50 is called polycythemia.

• increased blood viscosity increases risk of thromboembolism.

Cardiac Functioning

• 02 requirements are high the first few weeks of life

• normally, HR increases to provide adequate oxygen transport

• infant has little cardiac output reserve capacity

• cardiac output depends almost completely on HR until the heart is fully developed (age 5 year).

Compliance in the infant

• in infancy, muscle fibers are less developed and organized

• results in less functional capacity or less compliance

• less compliance means the infant is unable or less able to distend or expand the ventricles to achieve an increase stroke volume in order to compensate for increased demands

Severe Hypoxemia

• children respond with bradycardia

• cardiac arrest generally results from prolonged hypoxemia related to respiratory failure or shock

• in adults, hypoxemia usually results from direct insult to the heart.

• therefore, in children, bradycardia is a significant warning sign of cardiac arrest.

• approp Rx for hypoxemia reverses brady.

TESTS COMMONLY USED TO DIAGNOSIS CONGENITAL HEART GEFECTS

n Blood and urine tests

n ECG (Electrocardiogram)

n Echocardiogram

n Cardiac magnetic resonance imaging (MRI)

n Stress tests

n Chest X Ray

n Pulse Oximetry

n Cardiac Catheterization

Assessment of heart disorders in children

– Diagnostic tests

– Electrocardiogram

– Radiography

– Echocardiography

– Phonocardiography & magnetic resonance imaging

– Exercise testing

– Laboratory tests

Laboratory test

n Bacteriological – culture of group A streptococcus is the gold standard evidence of the previous infection.

n In children with cyanosis blood gas analysis and laboratory tests for homeostasis.

n In children with cyanotic heart disease, a number of haemostatic abnormalities are common, including thrombocytopenia and low levels of prothrombin and factors V, VII, and IX.

ELECTROCARDIOGRAPHY (ECG)

This is recording of the electrical changes, which occur within the heart during the cardiac cycle, from the body surface. The main areas, in which ECG can prove useful, are:

• analysis of abnormal rhythms;

• detection and localization of changes in the myocardium;

• detection of hypertrophy of walls in the atria and ventricles; -detection of changes in electrical activity due to pericardial disease;

• detection of changes in electrical activity of the heart consequent on general metabolic changes.

Additional valuable information may be obtained by recording ECG during physical exercise.

The standard placement for active electrodes of the chest leads in the heart region is as follows

n VI – the 4^th intercostal space on the right border of the sternum;

n V2 – the 4^th intercostal space on the left border of the sternum;

n V3 – IV rib on the left parasternal line;

n V4 – the 5^th intercostal space on the left midclavicular line;

n V5 – the 5 ^th intercostal space on the left anterior axillary line;

n V6 – the 5^th intercostal space on the left medium axillary line

n Leads II, III and aVF record changes from the lateral border of the heart, and chest leads overlie the interventricular septum and the anterior wall of the left ventricle.

n Atrial depolarization is the source of changes in electrical potentials, which cause the P wave. The QRS complex is due to ventricular depolarization, and the T wave is due to ventricular depolarization. Atrial depolarization is associated with very small electrical changes which are not recorded on the conventional surface ECG. The Q wave in an initial negative deflection in the QRS complex.

n The P-R interval (measured from the beginning of the P wave to beginning of the QRS complex) is normally less than 0.2 seconds in adult. The duration of the normal QRS complex is less than 0.12 seconds

n ECG must be examined systematically. A convenient method is as follows:

* determine the cardiac rate and rhythm;

* assess the P-R interval and the width of the QRS complex;

* examine the P wave and the QRS complex;

* examine the ST segment and T wave.

ECG in children of different age

n ECG of newborns and children of an early age is normally characterized by right ventricular dominants.

n I. P waves ieonatal ECG.

n a. P waves are normally upright in leads I, II, and AVF. Inverted P waves may indicate an abnormal atrial rhythm or dextracardia.

n b. Peaked P waves greater than 2.5 mm may indicate right atrial enlargement.

n c. Broad notched P waves greater than 0.08 seconds may indicate left atrial enlargement.

n II. PR interval.

n a. PR interval should not exceed 0.11 seconds.

n b. Prolonged PR interval is seen in primary AV conduction defects, endocardial cushion defects, digitalis effect, and bradicardia.

n III. QRS.

n a. Duration: less than 0.09 seconds.

n IV. QT interval.

n a. QT interval / RR interval should not exceed 0.44.

n b. Prolonged QT is seen in hypocalcaemia, hypokalemia, metabolic derangement and inherited defects.

n V. T wave.

n a. Birth to 5 days – normally upright in VI and V2, inverted in V5 and V6.

n b. Five days to adolescence – normally inverted in VI and V2 and upright in V5 and V6.

ECG in cardiac rhythm disorders can be different.

Sinus tachycardia. The cardiac impulse arises normally from the sinus node in sinus tachycardia, and ECG is normal in form. Sinus tachycardia may result from emotion, exercise, fever, hyperthyroidism and anaemia

Sinus bradycardia. ECG is normal in form, but the heart rate is less than 60 beats/minute. Sinus bradycardia occurs in trained sportsmen and in patients with increased intracranial pressure, myxoedema and jaundice.

Sinus arrhythmia. The cardiac impulse arises normally in the sinoatrial node,

n whose rhythmicity varies;

n the heart rate increases with inspiration and diminishes with expiration.

n ECG is normal apart from variation in the RR intervals.

n This arrhythmia is a normal finding in children after 3-4 years;

n it is increased by deep breathing and abolished by exercise.

Extrasystoles

n These arise from foci in the atria or ventricles, which stimulate the

n Heart before the next sinus beat is due. In ventricular extrasystoles

n P waves are absent and the QRS complexes are broad, the T wave pointing in the opposite direction to the major deflection of the QRS

n The extrasystole comes prematurely and is followed by a pause

n (The compensatory pause).

n ECG of the atrial extrasystole shows the P wave to be abnormal in form, but the QRS which follows it is normal

n The pause which follows the extrasystole is longer thaormal

n If an extrasystole follows each normal beat the pulse is said to be coupled (bigeminy)

n If the patient is being treated with digoxin the possibility of toxicity should be considered

Atrial fibrillation

n There is no coordinate atrial activity (either electrical or mechanical)

n in atrial fibrillation

n ECG shows (fibrillation) waves representing the atrial activity instead of P waves, especially in lead VI

n The QRS complexes are normal but occur irregularly

Atrioventricular block (heart block)

n In first-degree atrioventricular block the P-R interval exceeds 0.2 seconds and all atrial impulses reach the ventricles.

n When some impulses fail to reach the ventricles but others do reach them, then there is second-degree atrioventricular block.

n In third-degree (complete) atrioventricular block the atria and ventricles beat independently, i.e. they are dissociated.

n The ventricular rate is usually slow, 20-40 beats/minute, often erratic and may fail completely (ventricular standstill).

n In a routine X-ray of the chest the heart is seen as a flask-shaped

n Shadow, lying between the translucent lungs, about one-third of its area to the right of the midline and two-thirds to the left.

Common alterations in disease can be detected by assessing the heart’s position in the chest

n (pleural effusion, pneumothorax, scoliosis, dextracardia),

n the shape and size of the heart (increase in ventricular mass, left atrial

n enlargement),

n the shape and size of the aorta, the pulmonary vasculature.

ECHOCARDIOGRAM (HEART ULTRASOUND)

An echocardiogram uses sound waves to take a picture of your child’s heart. Specialized types of echocardiogram include a fetal echocardiogram, a transesophageal echocardiogram, a dobutamine stress echocardiogram, and a bubble study.

An echocardiogram is a test that uses sound waves to take a picture of your child’s heart. An echocardiogram is also called an echo. This test does not hurt and is completely safe. You should be able to stay with your child during the test.

Getting ready for an echocardiogram

Most children do not need any special preparation for an echocardiogram. However, if your child is under 3 years old or cannot lie still, he will need a sedative or general anaesthesia. These are special medicines that will help your child sleep for the test. An echocardiogram works best when the child does not move.

If your child does not need a sedative or general anaesthesia, he or she can eat and drink normally before and after the echo. If your child has a favourite toy, a security blanket, or a favourite videotape, please bring that along.

If your child is having a sedative or general anaesthesia for the test, he or she will need to stop eating and drinking several hours before the test.

What will happen during the echocardiogram

The person who will perform the test is specially trained to do echocardiograms. This person is called a sonographer.

The sonographer will first measure your child’s weight and height. She will bring you and your child to a special echo room.

Your child will lie on a special bed that can move up and down. Your child should take off his or her sweater, shirt, and other clothes above the waist.

The sonographer will put three stickers on your child’s chest or arms. These stickers are called electrodes. They are connected by wires to the echo machine. They record your child’s heartbeat during the test.

Next, the sonographer will put some jelly on your child’s chest and belly so that the probe can move easily over your child’s skin. The probe is like a camera that takes pictures of your child’s heart. It is about 15 centimetres (6 inches) long and has a rounded end that sits lightly on the jelly.

Most of the lights will be turned off so the sonographer can see the pictures on the computer screen. The sonographer will move the probe around to take pictures of your child’s heart from different angles. Pictures are taken from the stomach, over the chest, and from the neck. You can watch these pictures on the computer screen. All of the pictures are saved on the computer.

Your child will feel no pain during the echocardiogram. He or she may feel some pressure from the probe. At times, your child may hear a loud swooshing noise when the echo machine records the flow of the blood through the heart.

After the sonographer completes the pictures, she will make a report and show the images to one of the cardiologists, a heart specialist, who is reviewing echo studies that day. The cardiologist may choose to take more pictures at this time. This is a normal part of the test. During this time, your child will remain connected to the echo machine. The sonographer or nurse will let you know when your child can get dressed again.

An echocardiogram takes from 30 minutes to 90 minutes or more. Often the first echocardiogram that your child has will take a longer amount of time. The length of time of the test will also depend on why your child’s doctor asked for the test.

What is a fetal echocardiogram?

When an echocardiogram is done when the baby is still in the mother’s womb, it is called a fetal echocardiogram. This echo can detect malformations as early as 16 weeks into the pregnancy, when the parts of the baby’s heart become clearly visible. It is usually done if there is a family history of congenital heart disease, if chromosomal or other abnormalities are suspected, if the heartbeat is irregular, or if the mother has medical problems that might affect the development of the heart.

To have this test, the mother will have her stomach covered in a jelly to help transmit the sound waves and get good quality pictures. For this test, it is usually not necessary to drink water before the appointment.

What is a transesophageal echocardiogram (TEE)?

A transesophageal echocardiogram (TEE) is an echocardiogram carried out by putting a special probe down the throat. The probe is a thin flexible tube with a miniature camera on the end. The child is given a general anaesthetic during the procedure.

A transesophageal echo takes clearer pictures than a regular echo since it can get closer to the heart. A TEE is done if the pictures from the normal echo are not good enough, at the end of surgery, in the operating room, and sometimes during heart catheterization.

What is a dobutamine stress echocardiogram?

The dobutamine stress echo combines 2 tests: the regular echocardiogram and a drug-stimulated stress test. The child is given a drug called dobutamine through an IV. Dobutamine is a drug that makes the heart beat faster and stronger and increases blood pressure. It has an effect very similar to exercise.

This test is done in children to study how the walls of the heart move and how the blood flows in the coronary arteries when the heart is working hard. It enables doctors to see how the heart functions at its peak heart rate. This test is often done to explore the effect of exercise on the heart, and how fast the heart recovers from exercise. The dobutamine does not stay long in the body and has no lasting effects. Children may feel anxious during the test because they may feel hot and the heart beats fast, similar to when they are exercising.

What is a bubble study?

Sometimes a fluid called contrast medium is injected into your child’s bloodstream during the echocardiogram. This helps give a better picture of your child’s heart on the echocardiogram.

One type of contrast medium is saline (sterile salt water) mixed with a gas. Usually, the gas is carbon dioxide, the same gas that makes soda fizzy. When this solution is used it is called a bubble study.

A bubble study lets the cardiologist follow the path that the bubbles take through the bloodstream. This helps to find heart or lung problems.

The bubble study is safe. The bubble solution is easily absorbed into your child’s bloodstream.

Bicuspid Aortic Valve

Background

Sir William Osler was one of the first to recognize the bicuspid aortic valve as a common congenital anomaly of the heart. Leonardo da Vinci recognized the superior engineering advantages of the normal trileaflet valve. However, bicuspid aortic valve is mentioned only briefly in many pediatric and cardiology textbooks.

Definition

The normal aortic valve has 3 equal-sized leaflets or cusps with 3 lines of coaptation. A congenitally bicuspid aortic valve has 2 functional leaflets. Most have one complete line of coaptation. Approximately half of cases have a low raphe. Stenotic or partially fused valves caused by inflammatory processes, such as rheumatic fever, are not included.

Embryology

The embryonic truncus arteriosus is divided by the spiral conotruncal septum during development. The normal right and left aortic leaflets form at the junction of the ventricular and arterial ends of the conotruncal channel. The nonseptal leaflet (posterior) cusp normally forms from additional conotruncal channel tissue. Abnormalities in this area lead to the development of a bicuspid valve, often through incomplete separation (or fusion) of valve tissue.

Bicuspid aortic valve is often observed with other left-sided obstructive lesions such as coarctation of the aorta or interrupted aortic arch, suggesting a common developmental mechanism. Specific gene mutations have been isolated.

Anatomy

The bicuspid valve is composed of 2 leaflets or cusps, usually of unequal size.

Bicuspid aortic valve with unequal cusp size. Note eccentric commissure and raphe.

The larger leaflet is referred to as the conjoined leaflet. Two commissures (or hinge points) are present; usually, neither is partially fused. The presence of a partially fused commissure, which has also been called a high raphe, probably predisposes toward eventual stenosis. At least half of all congenitally bicuspid valves have a low raphe, which never attains the plane of the attachments of the two commissures and never extends to the free margin of the conjoined cusp. Redundancy of a conjoined leaflet may lead to prolapse and insufficiency.

Valve leaflet orientation and morphology can vary. A recent surgical study showed conjoined leaflets in 76% of specimens. Of these, fusion of the raphe was noted between the right and left cusps in 86%, and fusion was noted between the left and noncoronary cusps in only 3%. Of the valves without raphes, more than 30% of the leaflets were unequal in size.

Coronary arteries may be abnormal. A left-dominant coronary system (ie, posterior-descending coronary artery arising from the left coronary artery) is more commonly observed with bicuspid aortic valve. Rarely, the left coronary artery may arise anomalously from the pulmonary artery. The left main coronary artery may be up to 50% shorter in patients with a bicuspid aortic valve. Occasionally, the coronary ostium may be congenitally stenotic in association with bicuspid aortic valve.

The aortic root may be dilated. This dilatation has some similarities to the dilatation of the aorta seen in Marfan syndrome. The dilatation may involve the ascending aorta (most commonly) but may also involve the aortic root or transverse aortic arch. A recent study compared aortic dilation in children who had bicuspid aortic valve with and without coarctation of the aorta; the conclusion was that valve morphologic characteristics and function and age at the time of coarctation of the aorta repair had no impact to minimal impact on aortic dimensions.

Pathophysiology

With degeneration of aging valves, sclerosis and calcification can occur. The changes are similar to those in atherosclerotic coronary arteries. The bicuspid valve may also be completely competent, producing no regurgitant flow. However, redundancy and prolapse of cusp tissue can lead to valve regurgitation. Complications arise in as many as one third of patients over their lifetimes; this disorder, therefore, deserves close attention and medical follow-up.

Valve morphology may be predictive of problems of stenosis, insufficiency, or both. Fusion along the right or left leaflets is less commonly associated with stenosis or insufficiency in children. This arrangement is much more common in patients with coarctation of the aorta, whose valves function adequately. Fusion along the right and noncoronary leaflets is more frequently associated with pathologic changes of stenosis or insufficiency in the pediatric population.

Epidemiology

Frequency

United States

Bicuspid aortic valves may be present in as many as 1-2% of the population. Because the bicuspid valve may be entirely silent during infancy, childhood, and adolescence, these incidence figures may be underestimated and are not generally included in the overall incidence of congenital heart disease.

International

Incidence does not appear to be affected by geography.

Race

A recent report suggests much lower than expected prevalence in African-Americans.

Sex

The male-to-female ratio is 2:1 or greater. Sex is not a predictive variable in the natural history of bicuspid aortic valve. A recent prospective echocardiographic study iewborn infants showed a prevalence of bicuspid aortic valve in 7.1 per 1,000 male newborns versus 1.9 per 1,000 female newborns.

Age

Bicuspid aortic valve may be identified in patients of any age, from birth through the 11th decade of life. It may be only an incidental finding at autopsy. Bicuspid aortic valve may remain silent and be discovered as an incidental finding on echocardiographic examination of the heart.

Critical aortic stenosis and infective endocarditis may be considered relatively early sources of morbidity for patients with bicuspid aortic valve. Critical aortic stenosis may occur in infancy and may be associated with a bicuspid valve.

Occasionally, bicuspid aortic valve is diagnosed after a patient has developed infective endocarditis with systemic embolization.

Stenosis of a bicuspid aortic valve is more likely to develop in persons older than 20 years and is caused by progressive sclerosis and calcification. High levels of serum cholesterol have been associated with more rapidly progressive sclerosis of the congenitally bicuspid aortic valve.

Children who develop early progressive, pathologic changes in the bicuspid aortic valve are more likely to develop valve regurgitation than stenosis. Bicuspid aortic valve was identified in 167 (0.8%) of 20,946 young Italian military conscripts. Of these, 110 were found to have either mild or moderate aortic insufficiency.

Coronary Artery Fistula

Background

Coronary artery anomalies include anomalies of origin, termination, structure or course. Coronary artery fistulae (CAF) are classified as abnormalities of termination and are considered a major congenital anomaly.

A coronary artery fistula involves a sizable communication between a coronary artery, bypassing the myocardial capillary bed and entering either a chamber of the heart (coronary-cameral fistula)[1] or any segment of the systemic or pulmonary circulation (coronary arteriovenous fistula). The pathophysiology of these lesions is identical, and they are often collectively termed coronary arterial-venous fistulae (CAVFs). A coronary artery connection to the pulmonary artery (coronary-pulmonary artery fistula) may also be considered under this grouping; however, if a named coronary artery arises directly from the pulmonary trunk with absence of a direct aortic connection, this is classified as an anomalous origin of the coronary artery from the pulmonary artery.

Maude Abbott published the first pathological account of this condition in 1908. The first successful surgical closure of a coronary fistula was performed in 1947 by Bjork and Crafoord in a patient with a preoperative diagnosis of patent ductus arteriosus.

Most coronary artery fistulas are small, do not cause any symptoms, and are clinically undetectable until echocardiography or coronary arteriography is performed for an unrelated cause; they usually do not cause any complications and can spontaneously resolve. However, larger fistulae are usually 3 times the size of a normal caliber of a coronary artery and may or may not cause symptoms or complications.

Pathophysiology

Small fistulas usually do not cause any hemodynamic compromise. However, the larger fistulae can cause coronary artery steal phenomenon, which leads to ischemia of the segment of the myocardium perfused by the coronary artery. The pathophysiologic mechanism of coronary artery fistula is myocardial stealing or reduction in myocardial blood flow distal to the site of the coronary artery fistula connection. The mechanism is related to the diastolic pressure gradient and runoff from the coronary vasculature to a low-pressure receiving cavity. If the fistula is large, the intracoronary diastolic perfusion pressure progressively diminishes.

The coronary vessel attempts to compensate by progressive enlargement of the ostia and feeding artery. Eventually, myocardium beyond the site of the fistula’s origin is at risk for ischemia, which is most frequently evident in association with increased myocardial oxygen demand during exercise or activity. Over time, the coronary artery leading to the fistulous tract progressively dilates, which, in turn, may progress to frank aneurysm formation, intimal ulceration, medial degeneration, intimal rupture, atherosclerotic deposition, calcification, side-branch obstruction, mural thrombosis, and, rarely, rupture.

The factors that determine the hemodynamic significance of the fistulous connection include the size of the communication, the resistance of the recipient chamber, and the potential for development of myocardial ischemia. Occasionally, high-output congestive heart failure has been described.

Coronary artery fistulae may mimic the physiology of various heart lesions. Fistulae that drain (1) to the systemic veins or right atrium have a physiology similar to an atrial septal defect; (2) to the pulmonary arteries have physiology similar to a patent ductus arteriosus, (3) to the left atrium do not cause a left to right shunt but do cause a volume load similar to mitral regurgitation; and (4) to the left ventricle have physiology similar to that of aortic insufficiency.

Anatomy

Normally, 2 coronary arteries arise from the root of the aorta and taper progressively as they branch to supply the myocardium. A fistula occurs if a substantive communication arises that bypasses the myocardial capillary phase and communicates with a low-pressure cardiac cavity (atria or ventricle) or a branch of the systemic or pulmonary systems. Direct communication between a coronary artery and one of the cardiac chambers is noted. The origin of a fistula is rarely bilateral, involving both left and right coronary artery systems. Fistulous opening into a chamber or the drainage is mostly single or, rarely, double if both coronary artery systems are involved.

Normal thin-walled vessels present at the arteriolar level may drain into the cardiac cavity (arteriosinusoidal vessels) and venous communications (thebesian veins) to the right atrium. These small vessels do not steal significant nutrient flow and do not constitute fistulous connections. Fistulae can be small or large, dilated or ectatic, and tend to enlarge over time. Often, the limits of what constitutes a fistula and what constitutes a normal vessel are debated.

Major sites of origin of the fistulae are from the right coronary artery (40-60%), left anterior descending (30-60%), circumflex and a combination thereof. Most fistulae terminate in a venous chamber or vessel and, only rarely, into the left ventricle or the pericardium. The major sites of termination include the right side of the heart (90%), left ventricle, left atrium and the coronary sinus. The most frequent sites of termination in the right side of the heart, in descending order, are the right ventricle, right atrium, and pulmonary vasculature.

In the setting of cardiac outflow obstruction such as pulmonary atresia with intact septum, the term coronary-sinusoidal connections is preferred. In this setting, epicardial coronary blood may flow to and fro during the cardiac cycle. In systole, right ventricular flow decompresses via coronary-sinusoidal connections to the aorta in a reverse direction, while in diastole, the aorta perfuses the coronary artery in a normal antegrade fashion. This contrasts with coronary arteriovenous fistulae in the absence of outflow obstruction, in which coronary steal is the primary pathophysiologic problem. In pulmonary atresia and coronary-sinusoidal connections, myocardial ischemia, necrosis, fibrosis, and systemic desaturation may occur. Areas of coronary stenosis and/or interruption of the coronary system may complicate this abnormality.

Coronary fistula communications can be congenital and acquired. Congenital coronary artery fistulae may occur as an isolated finding or may appear in the context of other congenital cardiac anomalies or structural heart defects, most frequently in critical pulmonary stenosis or atresia with an intact interventricular septum and in pulmonary artery branch stenosis, tetralogy of Fallot, coarctation of the aorta, hypoplastic left heart syndrome, and aortic atresia.

Acquired coronary artery fistula may rarely arise as a consequence of trauma such as a gun shot wound or a stab wound. They can also occur after cardiac surgery or invasive cardiac catheterization with percutaneous transluminal coronary angioplasty, pacemaker implantation, or endomyocardial biopsy.

Embryology

Coronary artery fistulae are thought to arise as a persistence of sinusoidal connections between the lumens of the primitive tubular heart that supply myocardial blood flow in the early embryologic period. Coronary artery fistulae occur in the absence of any outflow obstruction. Another explanation may be faulty development of the distal branches of the coronary artery rectiform vascular network.

When these channels persist in association with outflow obstruction (eg, pulmonary atresia), they are a variant form of fistulae termed coronary-sinusoidal connections. Associated syndromes most often associated with coronary-sinusoidal connections include pulmonary atresia or stenosis with an intact ventricular septum.

Epidemiology

Frequency

United States

Coronary artery fistula accounts for 0.2-0.4% of congenital cardiac anomalies. Approximately 50% of pediatric coronary vasculature anomalies are coronary artery fistulae.

Mortality/Morbidity

Fistula-related complications are present in 11% of patients younger than 20 years and in 35% of patients older than 20 years.

Fistulae can be associated with the following complications:

· Myocardial ischemia

· Mitral valve papillary muscle rupture from chronic ischemia

· Ischemic cardiomyopathy

· Congestive heart failure from volume overload

· Bacterial endocarditis

· Sudden cardiac death

· Secondary aortic valve disease

· Secondary mitral valve disease

· Premature atherosclerosis

Small fistulas remain clinically silent and are recognized at routine echocardiography and autopsy. In the small fistulas, the myocardial blood supply is not compromised enough to cause symptoms. Spontaneous closure usually occurs; however, some can dilate over time.

Larger fistulae progressively enlarge over time, and complications, such as congestive heart failure, myocardial infarction, arrhythmias, infectious endocarditis, aneurysm formation, rupture, and death, are more likely to arise in older patients. Spontaneous closure has been rarely reported in the setting of large fistulas.

The mortality rate related to surgical repair of coronary artery fistula typically ranges from 0-4%. Variations that may increase surgical risk include the presence of giant aneurysms and a right coronary artery–to–left ventricle fistula. Complications of surgery include myocardial ischemia and/or infarction (reported in 3% of patients) and coronary artery fistula recurrence (4% of patients).

Race

No race predilection is noted.

Sex

No sex predilection is noted.

Age

Coronary artery fistula may present in patients at any age but is usually suspected early in childhood when a murmur is detected in an asymptomatic child or with symptoms of congestive heart failure. Older children with murmurs may present with symptoms of coronary insufficiency. In a multicenter review, appreciably more problems related to operative risks and postoperative complications occurred after age 20 years.

Congenital heart defect corrective surgeries – Overview

Congenital heart surgery; Patent ductus arteriosus ligation; Hypoplastic left heart repair; Tetralogy of Fallot repair; Coarctation of the aorta repair; Atrial septal defect repair; Ventricular septal defect repair; Truncus arteriosus repair; Total anomalous pulmonary artery correction; Transposition of great vessels repair; Tricuspid atresia repair; VSD repair; ASD repair; PDA ligation

Definition of Congenital heart defect corrective surgeries:

Congenital heart defect corrective surgeries fix or treat heart defects that a child is born with. A baby born with heart defects has congenital heart disease. Surgery is needed if the defects are dangerous to the child’ s health or well-being.

Description:

The surgeries described below are done to correct many different heart defects in children.

For more information about risks, how to prepare for surgery, and descriptions of open-heart and closed-heart surgery techniques, see: Pediatric heart surgery.

Patent ductus arteriosus (PDA) ligation

Before birth, there is a natural blood vessel between the aorta (the main artery to the body) and the pulmonary artery (the main artery to the lungs) called the ductus arteriosus. This opening usually closes shortly after birth. A PDA occurs when this opening fails to close after birth.
Sometimes the PDA can be closed with a procedure that does not involve surgery. The procedure is usually done in a laboratory that uses x-rays. In this procedure, the surgeon inserts a few small tubes into an artery in the leg and passes them up to the heart. There are no cuts, except for a tiny hole in the groin. Then, a small metal coil or another device is put into the child’s arteriosus artery. The coil or other device blocks the blood flow, and this corrects the problem.
Another method is to make a small surgical cut on the left side of the chest. The surgeon finds the PDA and either ties off the ductus arteriosus, or divides and cuts it. Tying off the ductus arteriosus is called ligation. This procedure may be done in the neonatal intensive care unit (NICU).

Coarctation of the aorta repair

Coarctation of the aorta occurs when a part of the aorta has a very narrow section, like in an hourglass timer.
To repair this defect, a cut is usually made on the left side of the chest, between the ribs. There are many ways to repair coarctation of the aorta.
The most common way to repair this is to cut the narrow section and make it bigger with a patch made of Gore-tex, a man-made (synthetic) material.
Another way to repair this problem is to remove the narrow section of the aorta and stitch the remaining ends together. This can usually be done in older children.
A third way to repair this problem is called a subclavian flap. First, a cut is made in the narrow part of the aorta. Then, a patch is taken from the left subclavian artery (the artery to the arm) to enlarge the narrow section of the aorta.
A fourth way to repair the problem is to connect a tube to the normal sections of the aorta, on either side of the narrow section. Blood flows through the tube and bypasses the narrow section.
A newer method does not require surgery. A small wire is placed through an artery in the groin and up to the aorta. A small balloon is then opened up in the narrow area. A stent or small tube is left there to help keep the artery open. The procedure is done in a laboratory with x-rays.

Atrial septal defect (ASD) repair

The atrial septum is the wall between the left and right atria (upper chambers) of the heart. There is a natural opening before birth that usually closes on its own when a baby is born. When the flap does not close, the child has an ASD.
Sometimes ASDs can be closed without open-heart surgery. First, the surgeon makes a tiny cut in the groin. Then the surgeon inserts tubes into a blood vessel that go into the heart. Next, two small umbrella-shaped “clamshell” devices are placed on the right and left sides of the septum. These two devices are attached to each other. This closes the hole in the heart. Not all medical centers do this procedure.
Open-heart surgery may also be done to repair ASD. Using open-heart surgery, the septum can be closed using stitches. Another way to cover the hole is with a patch.

Ventricular septal defect (VSD) repair

The ventricular septum is the wall between the left and right ventricles (lower chambers) of the heart. A hole in the ventricular septum is called a VSD.
By age 1, most small VSDs close on their own. However, those VSDs that do stay open after this age must be closed.
Larger VSDs, small ones in certain parts of the ventricular septum, or ones that cause heart failure or endocarditis (inflammation) need open-heart surgery. The hole in the septum is usually closed with a patch.
Some septal defects can be closed using heart catheterization. This procedure involves passing a small wire into the heart and placing a patch over the defect. It is guided by x-rays.

Tetralogy of Fallot repair

Tetralogy of Fallot is a heart defect that exists from birth (congenital). It usually includes four defects in the heart and causes the baby to turn a bluish color (cyanosis).
Open-heart surgery is needed, and it is often done when the child is between 6 months and 2 years old.
Different types of repairs are done, depending on the defects.

The ventricular septal defect is one repair, and it is described above.
The pulmonary valve is opened and the thickened muscle (stenosis) is removed.
A patch may be placed on the right ventricle and main pulmonary artery to improve blood flow to the lungs.

The child may have a shunt procedure done first. A shunt moves blood from one area to another. This is done if the open-heart surgery needs to be delayed because the child is too sick to go through surgery.

A shunt procedure requires making a cut between two of the ribs.
Once the child is older, the shunt is closed and the main repair in the heart is performed.

Transposition of the great vessels repair

In a normal heart, the aorta comes from the left side of the heart, and the pulmonary artery comes from the right side. In transposition of the great vessels, these arteries come from the opposite sides of the heart.
Correcting transposition of the great vessels requires open-heart surgery. If possible, this surgery is done shortly after birth.
The most common repair is called an arterial switch. The aorta and pulmonary artery are divided. The pulmonary artery is connected to the right ventricle, where it belongs. Then, the aorta and coronary arteries are connected to the left ventricle, where they belong.

Truncus arteriosus repair

Truncus arteriosus is a rare condition that occurs when the aorta, coronary arteries, and pulmonary artery all come out of one common trunk. This is a very complex defect, and it requires complex open-heart surgery to repair it.
Repair is usually done in the first few days or weeks of the infant’s life. The pulmonary arteries are separated from the aortic trunk, and any defects are patched. Usually, there is also a ventricular septal defect, and that is also closed. A connection is then placed between the right ventricle and the pulmonary arteries.
Most childreeed one or two more surgeries as they grow.

Tricuspid atresia repair

The tricuspid valve is found between the upper and lower chambers on the right side of the heart. Tricuspid atresia occurs when this valve is deformed, narrow, or missing.
Babies born with tricuspid atresia are blue because they cannot get blood to the lungs to pick up oxygen.
To get to the lungs, blood must cross an atrial septal defect (ASD), ventricular septal defect (VSD), or a patent ductus artery (PDA). (These conditions are described above.) This severely restricts blood flow to the lungs.
Soon after birth, a medicine called prostaglandin E may be given. This medicine will help keep the patent ductus arteriosus open so that blood can continue to flow to the lungs. However, this will only work for a while. Surgery is needed.
A series of shunts and surgeries may be necessary to correct this defect. The goal of this surgery is to allow blood from the body to flow into the lungs, and blood from the lungs to be pumped to the rest of the body.

Total anomalous pulmonary venous return (TAPVR) correction

TAPVR occurs when the pulmonary veins bring oxygen-rich blood from the lungs back to the right side of the heart, instead of the left side of the heart, where this usually occurs in healthy people.
This condition requires surgery to correct it. When the surgery is done will depend on how sick the baby is. The surgery may be done in the newborn period if the infant has severe symptoms. If it is not done right after birth, it is done in the first 6 months of the baby’s life.
TAPVR repair requires an open-heart surgery. The pulmonary veins are routed back to the left side of the heart, where they belong, and any abnormal connections are closed.
If a PDA is present, it is tied off and divided.

Hypoplastic left heart repair

This is a very severe heart defect that results from a severely underdeveloped left heart. If it is not treated, it causes death in most babies who are born with it. Operations to treat this defect are done at specialized medical centers. Usually surgery corrects this defect. A series of three heart operations is usually needed.
The first operation is done in the first week of the baby’s life. This is a complicated surgery where one blood vessel is created from the pulmonary artery and the aorta. This new vessel carries blood to the lungs and the rest of the body.
The second operation is usually done when the baby is 4 to 6 months old.
The third operation is done a year after the second operation.
A heart transplant is another option for this condition. But finding a donor heart for an infant is very difficult. Infant heart transplants can be done only at a few medical centers.

Open-Heart Surgery’s Use

The repair of many cardiac defects such as atrial septal defects, ventricular septal defects, AV canals, transposition of the great arteries, tetralogy of Fallot and other complex anomalies requires the use of cardiopulmonary bypass, stopping the heart, and opening the heart. Most pediatric heart procedures are open-heart procedures.

Description of Open-Heart Surgery

To get access to the heart, the surgeon has to open the chest. To do so, he or she has to cut through the breast bone (sternum). This is referred to as the sternotomy. The skin incision is generally smaller in size than the length of the breast bone, since the skin can be stretched to some extent. For repeat incisions (a redo-sternotomy) often the length is a little longer than the previous scar.

For many parents, the concept of a sternotomy raises much concern. Most parents are surprised to hear that a sternotomy is one of the safest and more comfortable incisions performed during surgery. Performing a sternotomy is nothing but an artificial fracture; at the end of the operation the two edges of the breast bone are put back together with steel wires. This usually does not lead to any deformities of the chest wall, even as a child grows. At the same time, performing a sternotomy does not prevent the progression of already existing chest wall deformities (e.g., “pigeon chest”).

Pain is sensed by the nerve endings in the affected tissues. In the bone, pain arises from movement at the site of a fracture. Infants don’t have much chest wall muscle mass to move the sternal edges and develop pain. For that reason, not surprisingly, most infants are discharged home on just ibuprofen and Tylenol.

After the chest is opened, a part (or all) of the thymus gland is removed. The thymus gland is involved in the immune system; however, its removal has not been shown to lead to any immune compromise. The removal of the thymus is necessary to allow the surgeon to see and operate on the heart. The heart sits in a thin, leather like sac called the pericardium. To get access to the heart, the pericardial sac has to be opened. The surgeon often removes a small portion of the pericardium, to be used later to patch holes in the heart or patch vessels to make them bigger. Often the removed piece is treated with a chemical called glutaraldehyde to increase the stiffness of the pericardium, making it easier to work with during surgery.

The removed pericardial piece is used during the operation as patch material for a variety of holes or defects within the heart. The removed piece of pericardium does not need to be replaced.

Risks and Complications of Open-Heart Surgery

All open-heart procedures carry risks related to the use of cardiopulmonary bypass. The safety of cardiopulmonary bypass has improved significantly over the years. Major complications are now exceedingly rare. Bypass times up to four to eight hours are well tolerated.

The risks of bypass itself include inadequate perfusion of organs or tissues, activation of a systemic inflammatory response, and embolization of air or particles. Especially concerning is the potential of embolization to the brain, but this risk should be quite low – less than 1 percent in most cases.

“Inadequate perfusion of organs and tissues” means that the bypass machine is not as efficient of a pump as your own heart, so some organs and tissues get a little less blood flow during surgery than they would normally. These organs protect themselves by slowing down. However, this is rare during modern cardiopulmonary bypass.

“Activation of a systemic inflammatory response” means that the heart-lung machine activates the body to release chemicals and cells that cause inflammation. This is why children after cardiopulmonary bypass can be somewhat swollen and their lungs can become “wet.” Lasix (a medicine that helps your child get rid of fluid by urinating) is usually given after surgery. “Embolization” occurs when a particle breaks loose and travels from one location in the body to another. Both air and clots can break lose and embolize, and can cause a potentially dangerous event (such as stroke). A potentially significant, yet rare, complication of cardiopulmonary bypass is neurologic injury resulting in stroke or seizures.

Bleeding is also a risk after open heart surgery. Due to the use of Heparin (a blood thinner) during bypass, bleeding sometimes occurs where we have placed sutures. Usually the bleeding is minimal and easily controlled with medications and bandages. The need for re-operation for bleeding following open-heart operations is low, about 2 percent.

In addition to the risks of bypass, the heart itself can be affected. First, the heart undergoes a period of cold ischemia (no blood flow) during most open-heart operations. Myocardial function may be compromised by this period of ischemia despite efforts to protect the heart muscle using cardioplegia and cooling. Second, the heart’s function may be decreased or “depressed” after surgery. The heart needs time to adapt to new anatomy and physiology after repair. Last, the heart rhythm may also be affected by open-heart procedures. Some patients require temporary or even permanent pacing (stimulation of the heart to assure a normal rhythm).

Preparing for Open-Heart Surgery

Patients requiring open-heart surgery will have had a complete evaluation by their cardiologist and cardiac surgeon.

The evaluation usually includes blood work, chest X-ray, an electrocardiogram, an echocardiogram and possibly a cardiac catheterization. All of this information helps guide the surgery and peri-operative care.

Blood is crossmatched to be available in the operating room or to prime the bypass machine if necessary.

Decision to Perform Open-Heart Surgery

When a patient’s cardiologist feels surgery may be indicated, the patient is discussed at Cincinnati Children’s Heart Institute’s weekly combined Cardiology-Cardiothoracic Surgery Case Management Conference.

The patient’s medical history, physical exam findings and all studies that have been performed are reviewed. The group then discusses your child’s case and decides on a recommendation on whether a procedure should be done, the timing of that procedure, and the type of procedure.

Often, the operatioeeded is clear-cut. However, more complex defects may have different possible approaches for either correction or palliation. Such cases benefit greatly from the input of many experts. Also, regardless of how good the pre-operative assessment, the anatomy is never really known until the surgeon is looking at the heart. Therefore, sometimes the operation done may change because of intra-operative findings.

References

а) Basic

1. Manual of Propaedeutic Pediatrics / S.O. Nykytyuk, N.I. Balatska, N.B. Galyash, N.O. Lishchenko, O.Y. Nykytyuk – Ternopil: TSMU, 2005. – 468 pp.

2. Kapitan T. Propaedeutics of children’s diseases and nursing of the child : [Textbook for students of higher medical educational institutions] ; Fourth edition, updated and translated in English / T. Kapitan – Vinnitsa: The State Cartographical Factory, 2010. – 808 pp.

3. Nelson Textbook of Pediatrics /edited by Richard E. Behrman, Robert M. Kliegman; senior editor, Waldo E. Nelson – 19^th ed. – W.B.Saunders Company, 2011. – 2680 p.

b) Additional

1. www.bookfinder.com/author/american-academy-of-pediatrics

2. www.emedicine.medscape.com

3. http://www.nlm.nih.gov/medlineplus/medlineplus.html