Marfan Syndrome
What is Marfan syndrome?
The Marfan syndrome is a genetic disorder that affects the body's connective tissues, or the tissues in between the main cells of each organ of the body.
All organs contain connective tissue and, hence, the manifestations of Marfan syndrome appear in many parts of the body, especially the skeletal system, the eyes, the heart and blood vessels and the lungs.
The term "syndrome" refers to the collection of physical findings that occur together often enough to provide a recognizable pattern that allows the diagnosis to be made. It was first described in a six year old girl by the French pediatrician, Antoine Marfan, in 1896.
Manifestations of Marfan syndrome
The heart is affected in nearly 80 percent of patients with this syndrome. The most important finding is enlargement or dilation of the aorta, the main blood vessel that carries blood to the body. This abnormality in connective tissue of the first few inches of the aorta allows the aorta to stretch sufficiently to cause tearing or rupture.
Additionally, as the aorta widens, the leaflets of the aortic valve may be stretched to a point where they fail to close completely and will thereby allow blood to leak back into the heart, causing the left ventricle to enlarge. If left untreated, the heart can go into failure.
Another valve of the heart that frequently is affected is the mitral valve, which may also leak causing the heart to become large and work harder.
In general, the skeletal system may be affected in different ways. A person with Marfan syndrome will usually be tall, slender and somewhat loose jointed or limber.
The arms, legs, fingers and toes may be disproportionately long when compared to the trunk.
Scoliosis is frequently common, and the breastbone may be either very prominent or depressed.
Lenses in eyes of patients with Marfan syndrome are dislocated in a high percentage of cases. This most often causes nearsightedness, and the degree of visual disturbance may be mild or quite severe. In addition, the retina of the eye may become detached.
The skin often exhibits stretch marks, known as stria atrophicae. These can occur in anyone particularly as a result of pregnancy or marked weight gain and loss. However, patients with Marfan syndrome tend to develop stria at an early age and without weight change. These stria tend to appear on the shoulders, hips and lower back.
The lungs also need connective tissue to provide stability and elasticity to the tiny air sacs. Although the altered lung elasticity rarely causes any noticeable problems, patients with Marfan syndrome may develop spontaneous collapse (or pneumothorax) of a lung at a rate of about 50 times greater than the general population. This can occur after a minor blow to the chest or out of the blue.
Marfan syndrome causes
The cause of the Marfan syndrome is now known. A gene located on chromosome 15 encodes a specialized protein called "fibrillin" that contributes to the production of normally functioning connective tissue in our body. In Marfan syndrome, a mutation of that gene occurs.
Unfortunately, not all patients with Marfan syndrome have the same abnormal genetic protein. There may be slight variations or mutations in the fibrillin gene, which can produce the same findings in all patients.
The gene is inherited as an autosomal dominant condition, which means that only one parent needs to have the mutation to pass it on to their children. Usually everyone in the same family who has the Marfan syndrome has the same variation or mutation.
Unrelated patients or families appear to have different mutations. Identifying the mutations is a very time-consuming job, and a routine medical test to diagnose the syndrome is not yet available.
How Marfan syndrome is diagnosed
Although Marfan syndrome is more common than previously thought -- it may affect one out of 3,000 to 5,000 individuals -- it remains an uncommon condition. Because of this, the diagnostic evaluation for this syndrome should be performed by physicians experienced with the condition. Evaluation includes a detailed family history and physical examination.
Since the syndrome involves many bodily systems, the syndrome can be divided into major or minor criteria.
Approximately 80 percent of patients with Marfan syndrome will have a positive family history, which is one major criterion of the syndrome. This requires a very specific diagnosis of the syndrome in other family members, not just someone who is unusually tall. In the rest of the patients, the syndrome results from a new mutation in the sperm and ova of the parents.
A second major criterion for diagnosing the syndrome involves the skeleton. The most consistent and reliable measure is an abnormally low ratio of the upper trunk of the body to the lower extremities. This ratio is generally less than 0.87 in African-Americans to 0.92 in Caucasians.
Another abnormal measurement includes the comparison of the arm span to the total height of the individual, where the arm span to height ratio exceeds 1.05. Other features include abnormalities of the sternum (breastbone), joint hyperextensibility, scoliosis, etc.
A third major criterion for this diagnosis is ocular, or related to the eyes. Virtually all patients with Marfan syndrome have myopia or nearsightedness.
About 70 percent of patients have ectopia lentis or dislocated lenses of the eyes. This may be very mild. Hence, determination of this abnormality requires dilation of the pupils and slit lamp examination by an experienced physician or practitioner.
The fourth major criterion is cardiovascular and includes aortic dilation or dissection.
Minor criteria include mitral valve prolapse, spontaneous pneumothorax, stretch marks, or recurrent incisional hernias.
In order for the diagnosis of Marfan syndrome to be made in the first identifiable case of a family, at least two major criteria in different systems and involvement of a third system must be present. If there is a positive family history, a major criterion in one system and involvement of either major or minor criteria in a second system will permit the diagnosis to be made.
Treating Marfan syndrome patients
Although there is no "cure" for this condition, effective treatment is available. Management and treatment of the Marfan syndrome are best discussed and understood by directing attention to the affected organ systems.
The Heart and Aorta: Perhaps one of the most well-known and frightening complications of this syndrome is the sudden rupture of the aorta. Recently, there has been much media attention regarding this tragic event in several athletes.
Therefore, the first line of defense is detection of this abnormality. It can only be accurately diagnosed and monitored through routine imaging techniques.
The most common of these is echocardiography, which can not only evaluate the size of the aorta and the progression but also the size of the heart and any involvement of the valves of the heart.
Routine echocardiography for those patients without obvious cardiovascular problems can be performed on a yearly basis. Enlargement of the aorta, particularly significant enlargement, is often monitored every six months to observe sudden increases in the size of the aorta or progressive enlargement, which may require treatment.
If the aortic valve begins to leak or if the aorta begins to enlarge excessively, surgical intervention by repairing or replacing either the valve or the enlarged aorta may be necessary.
Presently, Marfan patients are best advised to have this surgical intervention performed in a medical center that has a good deal of experience with the syndrome.
In some instances, magnetic resonance imaging (MRI) may be utilized to diagnose and regularly evaluate the size of the aorta after surgery or a rupture.
In addition to monitoring the size of the aorta once it is enlarged, several important medical recommendations are made.
Patients with an enlarged aorta will be advised against participating in any high impact or high isometric or static activities, such as weight lifting, football, basketball, etc. These activities can cause sudden excessive enlargement of the aorta leading to tearing or possible rupture.
In addition, medications, called "beta blockers," will be prescribed to regulate blood pressure and heart rhythm. These medications help blunt the sudden rise in blood pressure and/or heart rate that occur during activities and may prevent further enlargement of the aorta or reduce the aortic size. Stress tests may be ordered to help monitor the effectiveness of these drugs.
Skeletal System: In the skeletal system, severe curvature of the spine and/or deformity of the breast bone (sternum) represent the most serious problems, mostly related to the impact these have on lung function.
These skeletal abnormalities need to be evaluated by general surgeons or orthopedic surgeons who are experienced in the skeletal deformities, since many of them may require specialized surgery to correct them.
Various surgical procedures can stabilize the spine if there is significant spinal deformity, and techniques are available to correct severe depression of the breast bone.
The Eyes: The major problem with the eyes is dislocation of the lenses. In most patients, dislocation of the lens is a minor problem and may actually interfere with vision requiring special eyeglasses or contact lenses. On rare occasions the lens may have to be removed.
Because of the increased risk of retinal detachments, activities that involve blows to the head such as football, boxing and diving should be avoided.
Other Systems: Because of the risk of lung collapse (pneumothorax), Marfan syndrome patients should not subject themselves to extremes of air pressure or rapid changes in pressure. For example, Marfan syndrome patients should avoid riding in unpressurized aircraft or diving under water more than several feet.
As mentioned above, the stretch marks on the skin do not cause problems and, although they are unsightly, cannot be prevented.
Dental hygiene is especially important for people at risk for infection of the heart valves when there is leakage. It is certainly crucial for those with artificial valves. Good dental care and evaluation are also important if there is malalignment or malocclusion (faulty contact of the upper and lower teeth) of the jaw.
please see links to the right for Marfan Association UK for further help, advice and support
Wednesday, March 28, 2007
Wednesday, March 14, 2007
Interrupted Aortic Arch / Ventricular Septal Defect
Interrupted Aortic Arch / Ventricular Septal Defect
What is Interrupted Aortic Arch / ventricular septal defect?
The aorta is the main blood vessel that carries oxygen-rich blood away from the heart to the organs of the body. After it leaves the heart it ascends in the chest to give off blood vessels to the arms and head, then arches turns downward towards the lower half of the body.
Interrupted Aortic Arch (IAA) is the absence or discontinuation of a portion of the aortic arch. There are three types of Interrupted Aortic Arch, and they are classified according to the site of the interruption.
Type A: the interruption occurs just beyond the left subclavian artery. Approximately 30 percent to 40 percent of the infants with Interrupted Aortic Arch have Type A.
Type B : the interruption occurs between the left carotid artery and the left subclavian artery. Type B is the most common form of Interrupted Aortic Arch. It accounts for about 53 percent of reported cases.
Type C:
the interruption occurs between the innominate artery and the left carotid artery. Type C is the least common form of Interrupted Aortic Arch, accounting for about 4 percent of reported cases.
Interrupted Aortic Arch is thought to be a result of faulty development of the aortic arch system during the fifth to seventh week of fetal development. This defect is almost always associated with a large ventricular septal defect (VSD). Patients with Interrupted Aortic Arch (particularly those with type B) often have a chromosomal abnormality called DiGeorge syndrome. In addition to Interrupted Aortic Arch, patients with DiGeorge syndrome may have problems with low calcium, developmental delay, and immune system abnormalities.
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Problems caused by Interrupted Aortic Arch / ventricular septal defect
In patients with Interrupted Aortic Arch, oxygen-rich blood from the left side of the heart is not able to reach all areas of the body because of the defect in the aortic arch. An infant with Interrupted Aortic Arch must depend on an alternate way to get adequate blood flow to the lower body.
While the ductus arteriosus is open, infants may not have noticeable symptoms and may not be diagnosed. As the ductus arteriosus starts to close, however, the infant begins to show signs and symptoms of inadequate blood flow to the area after the interruption, resulting in severe symptoms including shock congestive heart failure.
If a ventricular septal defect is present, blood will be diverted (shunted) from the left side to the right side of the heart. This shunting causes an increase blood flow to the lungs, which leads to congestive heart failure as well.
What are the signs and symptoms of interrupted aortic arch with ventricular septal defect?
Signs and symptoms of poor perfusion or congestive heart failure may develop when the ductus arteriosus begins to close, usually within the first day or two of life.
The infant may develop weakness, fatigue, poor feeding, rapid breathing, fast heart rate, or low oxygen levels, particularly when measured in the legs and feet.
This condition can worsen and lead to shock. The infant will then be pale, mottled, cool, with decreased urine output and poor pulses especially in the lower extremities.
Diagnosing Interrupted Aortic Arch
Diagnosis of Interrupted Aortic Arch may be suspected based on the symptoms the infant has on presentation. It is then confirmed by an echocardiogram. Once the diagnosis is suspected and confirmed, treatment and surgical intervention are vitally important.
Interrupted aortic arch treatment
Immediate treatment includes the administration of a prostaglandin infusion. Prostaglandin is a medication that is administered intravenously and keeps the ductus arteriosus open. This allows blood flow to the lower body until surgery is done to re-establish continuity of the aortic arch.
Goals of treatment are aimed at stabilizing and supporting the infant until surgical intervention. Such treatment may include:
intubation (endotracheal tube placed in the airway to support breathing);
diuretic therapy to help the infant urinate excess fluid; administration of inotropic medications (medications to help improve the pumping action of the heart);
monitoring and correction of abnormal blood gases (carbon dioxide and oxygen levels in the blood) and electrolytes (potassium and calcium levels in the blood); and administration of nutrition.
The goal of surgery is to reconnect the aortic arch to create a continuous "tube" and close the ventricular septal defect. Surgery is typically performed urgently but after the infant is stabilized.
Open-heart surgery will be done to connect the two separate portions of the aorta, close the ventricular septal defect, and tie off (ligate) the patent ductus arteriosus.
Complications after Interrupted Aortic Arch repair may include residual obstruction or stenosis (narrowing) at the aortic repair site.
The aortic valve or the area below the valve are often small and may not grow, which can result in stenosis (narrowing) months or years following surgery.
Surgery results
The risk of complications both early and late following the repair of interrupted aortic arch with ventricular septal defect depends on a number of factors.
Very small size of the aortic valve region or significant instability in the preoperative period increase the chance of later problems.
Survival after complete repair of the aortic arch and ventricular septal defect in the newborn period is 90 percent or greater in most pediatric heart centers.
Long-term follow-up by the cardiologist to assess growth of the aortic valve region and the reconstructed aortic arch is essential. Reoperation to address further problems with these areas may be needed in 10 to 20 percent of patients.
What is Interrupted Aortic Arch / ventricular septal defect?
The aorta is the main blood vessel that carries oxygen-rich blood away from the heart to the organs of the body. After it leaves the heart it ascends in the chest to give off blood vessels to the arms and head, then arches turns downward towards the lower half of the body.
Interrupted Aortic Arch (IAA) is the absence or discontinuation of a portion of the aortic arch. There are three types of Interrupted Aortic Arch, and they are classified according to the site of the interruption.
Type A: the interruption occurs just beyond the left subclavian artery. Approximately 30 percent to 40 percent of the infants with Interrupted Aortic Arch have Type A.
Type B : the interruption occurs between the left carotid artery and the left subclavian artery. Type B is the most common form of Interrupted Aortic Arch. It accounts for about 53 percent of reported cases.
Type C:
the interruption occurs between the innominate artery and the left carotid artery. Type C is the least common form of Interrupted Aortic Arch, accounting for about 4 percent of reported cases.
Interrupted Aortic Arch is thought to be a result of faulty development of the aortic arch system during the fifth to seventh week of fetal development. This defect is almost always associated with a large ventricular septal defect (VSD). Patients with Interrupted Aortic Arch (particularly those with type B) often have a chromosomal abnormality called DiGeorge syndrome. In addition to Interrupted Aortic Arch, patients with DiGeorge syndrome may have problems with low calcium, developmental delay, and immune system abnormalities.
Return to Top
Problems caused by Interrupted Aortic Arch / ventricular septal defect
In patients with Interrupted Aortic Arch, oxygen-rich blood from the left side of the heart is not able to reach all areas of the body because of the defect in the aortic arch. An infant with Interrupted Aortic Arch must depend on an alternate way to get adequate blood flow to the lower body.
While the ductus arteriosus is open, infants may not have noticeable symptoms and may not be diagnosed. As the ductus arteriosus starts to close, however, the infant begins to show signs and symptoms of inadequate blood flow to the area after the interruption, resulting in severe symptoms including shock congestive heart failure.
If a ventricular septal defect is present, blood will be diverted (shunted) from the left side to the right side of the heart. This shunting causes an increase blood flow to the lungs, which leads to congestive heart failure as well.
What are the signs and symptoms of interrupted aortic arch with ventricular septal defect?
Signs and symptoms of poor perfusion or congestive heart failure may develop when the ductus arteriosus begins to close, usually within the first day or two of life.
The infant may develop weakness, fatigue, poor feeding, rapid breathing, fast heart rate, or low oxygen levels, particularly when measured in the legs and feet.
This condition can worsen and lead to shock. The infant will then be pale, mottled, cool, with decreased urine output and poor pulses especially in the lower extremities.
Diagnosing Interrupted Aortic Arch
Diagnosis of Interrupted Aortic Arch may be suspected based on the symptoms the infant has on presentation. It is then confirmed by an echocardiogram. Once the diagnosis is suspected and confirmed, treatment and surgical intervention are vitally important.
Interrupted aortic arch treatment
Immediate treatment includes the administration of a prostaglandin infusion. Prostaglandin is a medication that is administered intravenously and keeps the ductus arteriosus open. This allows blood flow to the lower body until surgery is done to re-establish continuity of the aortic arch.
Goals of treatment are aimed at stabilizing and supporting the infant until surgical intervention. Such treatment may include:
intubation (endotracheal tube placed in the airway to support breathing);
diuretic therapy to help the infant urinate excess fluid; administration of inotropic medications (medications to help improve the pumping action of the heart);
monitoring and correction of abnormal blood gases (carbon dioxide and oxygen levels in the blood) and electrolytes (potassium and calcium levels in the blood); and administration of nutrition.
The goal of surgery is to reconnect the aortic arch to create a continuous "tube" and close the ventricular septal defect. Surgery is typically performed urgently but after the infant is stabilized.
Open-heart surgery will be done to connect the two separate portions of the aorta, close the ventricular septal defect, and tie off (ligate) the patent ductus arteriosus.
Complications after Interrupted Aortic Arch repair may include residual obstruction or stenosis (narrowing) at the aortic repair site.
The aortic valve or the area below the valve are often small and may not grow, which can result in stenosis (narrowing) months or years following surgery.
Surgery results
The risk of complications both early and late following the repair of interrupted aortic arch with ventricular septal defect depends on a number of factors.
Very small size of the aortic valve region or significant instability in the preoperative period increase the chance of later problems.
Survival after complete repair of the aortic arch and ventricular septal defect in the newborn period is 90 percent or greater in most pediatric heart centers.
Long-term follow-up by the cardiologist to assess growth of the aortic valve region and the reconstructed aortic arch is essential. Reoperation to address further problems with these areas may be needed in 10 to 20 percent of patients.
Ebstein's Anomaly
Ebstein's Anomaly
What is Ebstein's Anomaly?
Ebstein's anomaly is an abnormality in the tricuspid valve. The tricuspid valve separates the right atrium (the chamber that receives blood from the body) from the right ventricle (the chamber that pumps blood to the lungs).
In Ebstein's anomaly, two leaflets of the tricuspid valve are displaced downward into the pumping chamber and the third leaflet is elongated and may be adherent to the wall of the chamber. These abnormalities cause the tricuspid valve to leak blood backwards into the right atrium when the right ventricle contracts and as a result, the right atrium becomes enlarged and. If severe enough, congestive heart failure can result. More rarely, the valve is so deformed that it will not allow blood to flow easily in the normal direction (right atrium to right ventricle).
If pressure within the right atrium becomes very high due to the excessive backflow into it, a communication between the right atrium and left atrium known as the foramen ovale (which is normally present in the fetus and usually closes after birth) will remain open. This connection allows unoxygenated ("blue") blood to flow from the right atrium, bypassing the lungs and going directly to the body. This will result in lower oxygen levels in the blood.
Ebstein's anomaly may occur with other heart lesions, such as pulmonary valve stenosis or atresia, atrial septal defect or ventricular septal defect. In addition, many patients with Ebstein's anomaly have an accessory (extra) conduction pathway in the heart (Wolff-Parkinson-White syndrome) leading to episodes of abnormal fast heart rate (supraventricular tachycardia.)
What signs or symptoms are associated with Ebstein's anomaly?
Ebstein's anomaly can range from very mild, with little symptoms, to very severe.Many patients with milder forms of Ebstein's anomaly do not have symptoms are diagnosed due to the presence of a heart murmur. Abnormal or extra heart sounds may also be present on the physical examination.
Some babies and children have bluish discoloration to their lips and nail beds (cyanosis), due to the flow of blood from the right atrium to the left atrium. Children may complain that their heart races, skips a beat, or "hiccoughs." They may tire more easily than other children or become short of breath, particularly during play. In adolescents and young adults, the sensation of "heart skipping" (palpitations) or fast heart rate, shortness of breath, and chest pain may be the first symptoms. Growth and development are usually normal in patients with Ebstein's anomaly.
Severely affected babies are often critically ill at birth, with low oxygen saturations (cyanosis) and heart failure requiring intensive care.
What is Ebstein's Anomaly?
Ebstein's anomaly is an abnormality in the tricuspid valve. The tricuspid valve separates the right atrium (the chamber that receives blood from the body) from the right ventricle (the chamber that pumps blood to the lungs).
In Ebstein's anomaly, two leaflets of the tricuspid valve are displaced downward into the pumping chamber and the third leaflet is elongated and may be adherent to the wall of the chamber. These abnormalities cause the tricuspid valve to leak blood backwards into the right atrium when the right ventricle contracts and as a result, the right atrium becomes enlarged and. If severe enough, congestive heart failure can result. More rarely, the valve is so deformed that it will not allow blood to flow easily in the normal direction (right atrium to right ventricle).
If pressure within the right atrium becomes very high due to the excessive backflow into it, a communication between the right atrium and left atrium known as the foramen ovale (which is normally present in the fetus and usually closes after birth) will remain open. This connection allows unoxygenated ("blue") blood to flow from the right atrium, bypassing the lungs and going directly to the body. This will result in lower oxygen levels in the blood.
Ebstein's anomaly may occur with other heart lesions, such as pulmonary valve stenosis or atresia, atrial septal defect or ventricular septal defect. In addition, many patients with Ebstein's anomaly have an accessory (extra) conduction pathway in the heart (Wolff-Parkinson-White syndrome) leading to episodes of abnormal fast heart rate (supraventricular tachycardia.)
What signs or symptoms are associated with Ebstein's anomaly?
Ebstein's anomaly can range from very mild, with little symptoms, to very severe.Many patients with milder forms of Ebstein's anomaly do not have symptoms are diagnosed due to the presence of a heart murmur. Abnormal or extra heart sounds may also be present on the physical examination.
Some babies and children have bluish discoloration to their lips and nail beds (cyanosis), due to the flow of blood from the right atrium to the left atrium. Children may complain that their heart races, skips a beat, or "hiccoughs." They may tire more easily than other children or become short of breath, particularly during play. In adolescents and young adults, the sensation of "heart skipping" (palpitations) or fast heart rate, shortness of breath, and chest pain may be the first symptoms. Growth and development are usually normal in patients with Ebstein's anomaly.
Severely affected babies are often critically ill at birth, with low oxygen saturations (cyanosis) and heart failure requiring intensive care.
Friday, March 02, 2007
Non-surgical technique replaces the need for open-heart surgery
Due to this being a very new proceedure by Professor Philipp Bonhoeffer for the Pulmonary Valve replacment I am leaving the links for the description and the images for you to see for yourself on the GOSH (Great Ormond Street) web site. So please go and take a look..
valve replacment
Images
valve replacment
Images
Pulmonary Valvar Stenosis
Pulmonary Valvar Stenosis
What is Pulmonary Valvar Stenosis?
Pulmonary stenosis is a condition characterized by obstruction to blood flow from the right ventricle to the pulmonary artery.
This obstruction is caused by narrowing or stenosis at one or more of several points from the right ventricle to the pulmonary artery. It includes obstruction from thickened muscle below the pulmonary valve, narrowing of the valve itself, or narrowing of the pulmonary artery above the valve.
The most common form of pulmonary stenosis is obstruction at the valve itself, referred to as pulmonary valvar stenosis.
The normal pulmonary valve consists of three thin and pliable valve leaflets. When the right ventricle ejects blood into the pulmonary artery, the normal pulmonary valve leaflets spread apart easily and cause no obstruction (blockage) to outflow of blood from the heart.
Pulmonary valve stenosis occurs when abnormalities of the pulmonary valve lead to narrowing and obstruction between the right ventricle and the pulmonary artery.
Most commonly, the pulmonary valve leaflets are thickened and fused together along their separation lines (commissures).
When the tissue is thickened, the leaflets become less pliable than normal and this also contributes to the obstruction. At times, the diameter of the pulmonary valve itself is small or hypoplastic.
When the pulmonary valve is obstructed, the right ventricle must work harder to eject blood into the pulmonary artery. To compensate for this additional workload, the muscle of the right ventricle (the myocardium) gradually thickens to provide additional strength to right ventricular ejection.
The increased right ventricular muscle, known as hypertrophy, is rarely a problem in itself, but instead is an indication that significant valve obstruction exists.
When the pulmonary valve is severely obstructed, especially in newborns with critical degrees of pulmonary stenosis, the right ventricle cannot eject sufficient volume of blood flow into the pulmonary artery.
In these instances, blue blood bypasses the right ventricle flowing from the right atrium to left atrium, through the foramen ovale, a communication or "hole" between these two chambers that is normally present in newborns. Newborns with critical pulmonary stenosis therefore will have cyanosis (blue discoloration of the lips and nailbeds) due to lower oxygen levels in their blood.
Right ventricular failure rarely occurs with pulmonary valve stenosis.
Pulmonary valvar stenosis signs and symptoms
Children with pulmonary valvar stenosis are usually asymptomatic and in normal health.
A heart murmur is the most common sign detected by a physician indicating that a valve problem may be present. Children with mild-to-moderate degrees of pulmonary valve stenosis have easily detectable heart murmurs, but typically do not have any symptoms.
Symptoms occur only with severe pulmonary valve stenosis.
A newborn with critical pulmonary valve stenosis develops cyanosis in the first few days of life. This is due to diminished volume of blood flow into the lungs, together with a shunt of blue blood from right to left atrium.
A newborn with critical pulmonary stenosis presents an emergency situation that requires immediate treatment, either balloon dilation of the valve or surgery.
In an older child, severe pulmonary valve stenosis may cause easy fatigue or shortness of breath with physical exertion. Severe pulmonary valve stenosis rarely results in right ventricular failure or sudden death.
Diagnosing pulmonary valvar stenosis
The diagnosis of pulmonary stenosis is usually first suspected because a physician detects a heart murmur.
The heart murmur of pulmonary stenosis is a turbulent noise caused by ejection of blood through the obstructed valve.
There is often an associated click sound when the thickened valve snaps to its open position. These sounds can be detected through careful examination of the heart by a physician well-trained in cardiac diagnosis.
Other testing may confirm the presence of pulmonary stenosis and help to document its severity.
The electrocardiogram is typically normal in the presence of mild pulmonary stenosis. With moderate-to-severe pulmonary stenosis the electrocardiogram may show enlargement of the right ventricle and thickening of its muscle.
The echocardiogram is the most important non-invasive test to detect and evaluate pulmonary valve stenosis. The echocardiogram accurately documents that the obstruction is present at the valve level and Doppler studies are used to estimate the degree of obstruction.
The echocardiogram is also important to exclude other problems that may be associated with pulmonary stenosis, such as an atrial septal defect (ASD) or ventricular septal defect (VSD).
Cardiac catheterization is an invasive technique that enables physicians to accurately measure the degree of pulmonary stenosis that is present. During cardiac catheterization, pressure measurements are made above and below the valve to define the amount of obstruction and motion pictures are taken to visualize the pulmonary valve.
During the past 15 years, echocardiography has generally replaced cardiac catheterization for the detection and measurement of pulmonary valve stenosis. Cardiac catheterization is rarely needed to make the diagnosis but, instead, is typically done to perform a balloon dilation procedure described below.
Pulmonary valvar stenosis treatments
Children with mild pulmonary valve stenosis rarely require treatment. Patients with mild pulmonary valve stenosis are healthy, can participate in all types of physical activities and sporting events, and lead normal lives.
Mild pulmonary valve stenosis in childhood rarely progresses after the first year of life. However, mild pulmonary stenosis in a young infant may progress to more severe degrees and requires careful follow-up.
Children with moderate-to-severe degrees of pulmonary stenosis require treatment, the timing of which is often elective.
The type of treatment required depends on the type of valve abnormality present. Most commonly, the stenotic pulmonary valve is of normal size, and the obstruction is due to fusion along the commissures or lines of valve leaflet opening.
This "typical" form of pulmonary valve stenosis responds very nicely to balloon dilation. Balloon dilation valvuloplasty is performed at the time of cardiac catheterization and does not require open-heart surgery.
In the newborn, balloon dilation for critical pulmonary valve stenosis can be a technically challenging procedure as these newborns are often critically ill and unstable.
More typically, in older children the procedure is performed electively on an outpatient basis.
Open-heart surgical procedures are required for more complex valves, where balloon dilation is not sufficient therapy. These valves may be obstructed by thick and dysplastic leaflet tissue (such as in patients with Noonan Syndrome), and the diameter of the valve itself may be small in some cases.
For these conditions surgical pulmonary valvotomy (opening of the valve), partial valvectomy (removal of a portion of the leaflet), and possibly a transannular patch (patch from the right ventricle to pulmonary artery) may be required during the open-heart surgery repair.
What is Pulmonary Valvar Stenosis?
Pulmonary stenosis is a condition characterized by obstruction to blood flow from the right ventricle to the pulmonary artery.
This obstruction is caused by narrowing or stenosis at one or more of several points from the right ventricle to the pulmonary artery. It includes obstruction from thickened muscle below the pulmonary valve, narrowing of the valve itself, or narrowing of the pulmonary artery above the valve.
The most common form of pulmonary stenosis is obstruction at the valve itself, referred to as pulmonary valvar stenosis.
The normal pulmonary valve consists of three thin and pliable valve leaflets. When the right ventricle ejects blood into the pulmonary artery, the normal pulmonary valve leaflets spread apart easily and cause no obstruction (blockage) to outflow of blood from the heart.
Pulmonary valve stenosis occurs when abnormalities of the pulmonary valve lead to narrowing and obstruction between the right ventricle and the pulmonary artery.
Most commonly, the pulmonary valve leaflets are thickened and fused together along their separation lines (commissures).
When the tissue is thickened, the leaflets become less pliable than normal and this also contributes to the obstruction. At times, the diameter of the pulmonary valve itself is small or hypoplastic.
When the pulmonary valve is obstructed, the right ventricle must work harder to eject blood into the pulmonary artery. To compensate for this additional workload, the muscle of the right ventricle (the myocardium) gradually thickens to provide additional strength to right ventricular ejection.
The increased right ventricular muscle, known as hypertrophy, is rarely a problem in itself, but instead is an indication that significant valve obstruction exists.
When the pulmonary valve is severely obstructed, especially in newborns with critical degrees of pulmonary stenosis, the right ventricle cannot eject sufficient volume of blood flow into the pulmonary artery.
In these instances, blue blood bypasses the right ventricle flowing from the right atrium to left atrium, through the foramen ovale, a communication or "hole" between these two chambers that is normally present in newborns. Newborns with critical pulmonary stenosis therefore will have cyanosis (blue discoloration of the lips and nailbeds) due to lower oxygen levels in their blood.
Right ventricular failure rarely occurs with pulmonary valve stenosis.
Pulmonary valvar stenosis signs and symptoms
Children with pulmonary valvar stenosis are usually asymptomatic and in normal health.
A heart murmur is the most common sign detected by a physician indicating that a valve problem may be present. Children with mild-to-moderate degrees of pulmonary valve stenosis have easily detectable heart murmurs, but typically do not have any symptoms.
Symptoms occur only with severe pulmonary valve stenosis.
A newborn with critical pulmonary valve stenosis develops cyanosis in the first few days of life. This is due to diminished volume of blood flow into the lungs, together with a shunt of blue blood from right to left atrium.
A newborn with critical pulmonary stenosis presents an emergency situation that requires immediate treatment, either balloon dilation of the valve or surgery.
In an older child, severe pulmonary valve stenosis may cause easy fatigue or shortness of breath with physical exertion. Severe pulmonary valve stenosis rarely results in right ventricular failure or sudden death.
Diagnosing pulmonary valvar stenosis
The diagnosis of pulmonary stenosis is usually first suspected because a physician detects a heart murmur.
The heart murmur of pulmonary stenosis is a turbulent noise caused by ejection of blood through the obstructed valve.
There is often an associated click sound when the thickened valve snaps to its open position. These sounds can be detected through careful examination of the heart by a physician well-trained in cardiac diagnosis.
Other testing may confirm the presence of pulmonary stenosis and help to document its severity.
The electrocardiogram is typically normal in the presence of mild pulmonary stenosis. With moderate-to-severe pulmonary stenosis the electrocardiogram may show enlargement of the right ventricle and thickening of its muscle.
The echocardiogram is the most important non-invasive test to detect and evaluate pulmonary valve stenosis. The echocardiogram accurately documents that the obstruction is present at the valve level and Doppler studies are used to estimate the degree of obstruction.
The echocardiogram is also important to exclude other problems that may be associated with pulmonary stenosis, such as an atrial septal defect (ASD) or ventricular septal defect (VSD).
Cardiac catheterization is an invasive technique that enables physicians to accurately measure the degree of pulmonary stenosis that is present. During cardiac catheterization, pressure measurements are made above and below the valve to define the amount of obstruction and motion pictures are taken to visualize the pulmonary valve.
During the past 15 years, echocardiography has generally replaced cardiac catheterization for the detection and measurement of pulmonary valve stenosis. Cardiac catheterization is rarely needed to make the diagnosis but, instead, is typically done to perform a balloon dilation procedure described below.
Pulmonary valvar stenosis treatments
Children with mild pulmonary valve stenosis rarely require treatment. Patients with mild pulmonary valve stenosis are healthy, can participate in all types of physical activities and sporting events, and lead normal lives.
Mild pulmonary valve stenosis in childhood rarely progresses after the first year of life. However, mild pulmonary stenosis in a young infant may progress to more severe degrees and requires careful follow-up.
Children with moderate-to-severe degrees of pulmonary stenosis require treatment, the timing of which is often elective.
The type of treatment required depends on the type of valve abnormality present. Most commonly, the stenotic pulmonary valve is of normal size, and the obstruction is due to fusion along the commissures or lines of valve leaflet opening.
This "typical" form of pulmonary valve stenosis responds very nicely to balloon dilation. Balloon dilation valvuloplasty is performed at the time of cardiac catheterization and does not require open-heart surgery.
In the newborn, balloon dilation for critical pulmonary valve stenosis can be a technically challenging procedure as these newborns are often critically ill and unstable.
More typically, in older children the procedure is performed electively on an outpatient basis.
Open-heart surgical procedures are required for more complex valves, where balloon dilation is not sufficient therapy. These valves may be obstructed by thick and dysplastic leaflet tissue (such as in patients with Noonan Syndrome), and the diameter of the valve itself may be small in some cases.
For these conditions surgical pulmonary valvotomy (opening of the valve), partial valvectomy (removal of a portion of the leaflet), and possibly a transannular patch (patch from the right ventricle to pulmonary artery) may be required during the open-heart surgery repair.
Truncus Arteriosus
Truncus Arteriosus
What is Truncus Arterious?
Normally there are two main blood vessels leaving the heart: the aorta carrying blood to the body and the pulmonary artery that branches immediately to carry blood to each lung.
Instead of having a separate pulmonary artery and aorta, each with their own three-leafed valves, a baby with truncus arteriosus has only one great blood vessel or trunk leaving the heart, which then branches into blood vessels that go to the lungs and the body.
This great vessel usually has one large valve which may have between two and five leaflets. Usually this great vessel sits over both the left and right ventricle. The upper portion of the wall between these two chambers is missing resulting in what is known as a ventricular septal defect (VSD). In rare cases, the ventricular septal defect is absent.
Truncus arteriosus signs and symptoms
A baby with truncus arteriosus usually begins to have problems in the first week of life. Their oxygen levels are often slightly lower than normal resulting in cyanosis.
Because of the excessive amount of blood flow to the lungs with this anomaly, congestive heart failure (CHF) develops in the first week or two of life. On chest X-ray, the heart looks big and the lung fields look hazy indicating pulmonary overcirculation.
Signs of congestive heart failure are rapid breathing, shortness of breath, wheezing, grunting or very noisy breathing, nasal flaring, retractions, and restlessness.
The liver may be large due to a backup of blood or systemic congestion. Neck vein distention, poor feeding, and facial swelling are also seen.
Most often parents report rapid breathing, poor feeding, and a bluish color of the skin, especially around the mouth and nose. The signs and symptoms often increase when the infant eats.
Truncus arteriosus diagnosis
While the diagnosis may be suspected by physical examination, the echocardiogram will confirm the presence of truncus arteriosus. The anatomy of the great vessels, the single, complex truncal valve and the ventricular septal defect are easily seen.
A cardiac catheterization may be done on rare occasions if anatomy appears very unusual, or the diagnosis is made later as information is needed regarding the pressures in the pulmonary arteries. In most cases, however, the echocardiogram gives enough information to plan for surgery.
Treating truncus arteriosus
Initial treatment begins with stabilizing the infant. Medications to control congestive heart failure such as diuretics are often begun.
Ensuring good nutrition may require the use of a feeding tube or intravenous hyperalimentation. Surgical correction is typically carried out in the first few weeks of life after the infant is maximally stabilized.
The surgical repair of truncus arteriosus requires the use of heart-lung bypass machine support. It involves three major components:
Separating the pulmonary arteries from the main truncus (the truncus will remain as the first part of the aorta);
closure of the ventricular septal defect using a patch
creating a connection between the right ventricle and the pulmonary arteries using a valved conduit, usually a homograft pulmonary artery.
Most infants will require a period of very close monitoring in the Cardiac Intensive Care Unit while their heart function recovers from the major reconstruction.
The use of mechanical ventilation, special monitoring lines, and strong intravenous medications is typical during this period.
Gradually, as the heart function stabilizes, the supporting measures may be withdrawn and conversion to oral medications and attention to feeding dominates the management program.
Time in hospital following surgery may vary from one to three weeks in most cases.
Truncus arteriosus treatment results
Currently over 90 percent of children survive repair of truncus arteriosus. As the child grows, they will be followed by their cardiologist.
Typically, there will be no physical restrictions imposed on the child. As a child grows, the conduit that was used to connect the right ventricle and pulmonary arteries will not, and this will lead to obstruction to blood flow. The progression of this narrowing is easily followed by the cardiologist using physical examination and echocardiograms.
Recommendation for surgery to replace the right ventricle to pulmonary artery conduit with a larger one is usually made long before any symptoms would be evident.
This conduit will often need to be replaced two or three times during childhood to accommodate for growth. These operations are typically tolerated very well with a hospitalization of less than a week.
Problems with the truncal valve are more serious and can significantly affect the early and late mortality of these children. The more leaky (or narrowed) this valve is, the greater the chance that some intervention has to be done sooner than later (on average within 5 to 7 years) to prevent severe damage to the heart.
Delayed Sternal Closure
On occasion after an open-heart procedure, the child’s hemodynamics may be tenuous. Added to that, not infrequently there is some swelling of the heart muscle from surgery and the inflammation induced by the heart-lung machine.
For that reason, at times surgeons elect to leave the chest open only to close it a few days later. In this way, the breastbone is prevented from pushing on the heart in the most critical and early hours after an operation. Despite this, the heart itself is not exposed; a layer of soft protective material is sewn to the skin edges to provide coverage of the heart, along with sterile bandages.
To minimize the slightly increased risk of infection, antibiotics are continued during the time the chest is open. Generally, the chest is closed in the intensive care unit under the same heavy sedation and analgesia that is provided to the infant during this time.
Intraaortic Balloon Pump
The intraaortic balloon pump (IABP) is a device used in some critically ill patients to help reduce the work of the failing heart. The IABP is sometimes used during cardiac surgery to help remove the patient from the heart-lung bypass machine. It is sometimes used to help the heart of severely ill patient who is awaiting a cardiac transplant. At times it is used for a patient suffering from cardiogenic shock, a condition when the heart cannot pump well enough to keep adequate blood pressures.
The IABP is a long tube (catheter) with a collapsed, 8-inch, sausage-shaped plastic balloon at its tip. The catheter is inserted in an artery in the groin. The doctor directs the tube through the artery and positions it in the aorta. A pump is attached to the hub end of the catheter. The balloon is rapidly inflated and deflated using the heartbeat as a trigger. The end result is increased blood flow to the body at less cost to the heart.
Since blood clots can form around the catheter, blood thinners (anticoagulants) must be used after inserting the IABP. These clots can dislodge and embolize to other parts of circulation, causing blockage of arteries or even stroke. Although IABP can be used for weeks, when the catheter is left in for more than a few days, there is risk of infection. The IABP itself is rarely the cause of death. The disease requiring its use is usually responsible.
Left Ventricular Assist Device (LVAD)
A left ventricular assist device (LVAD) is a mechanical pump that helps a weakened heart pump blood throughout the body. It is typically used as a "bridge-to-transplant", but on occasion it is used in place of ECMO support, while the heart recovers. More recently, at some centers the LVAD device is being provided as an alternative to transplant or "destination therapy."
These devices are mostly geared toward adults, although some recent progress has been made in developing LVAD support for children. Often in the pediatric setting LVAD is used in the place of ECMO when the problem is strictly limited to the left side of the heart and the lungs appear to be fine. Although a right ventricular assist device (RVAD) can also be implemented when the right side of the heart is failing, generally ECMO support is preferred in that setting.
There are a variety of LVAD devices, but the one used most commonly in the pediatric setting is called the Biomedicus pump. Risk of bleeding and the need for anticoagulation (and therefore the need for transfusion of blood products) may be less with LVAD than ECMO.
Post-Pericardiotomy Syndrome (PPS)
Post-pericardiotomy syndrome is a condition that develops in about 2 to 15% of patients after open heart surgery. In this condition, the patient typically develops chest discomfort, fever and evidence of "inflammation" on blood tests. Although the etiology is unknown, it is believed to be some kind of immunologic reaction to the heart and pericardium as consequence of surgery.
The condition often occurs 1 to 2 weeks after open heart surgery and is associated with developing a pericardial effusion (fluid around the heart). An echocardiogram and EKG are performed and treatment is initiated based on signs and symptoms and the size of the pericardial effusion. If the fluid collection is large enough to be compromising heart function, the doctors may recommend tapping and removing the fluid under ultrasound guidance. Otherwise medical therapy is often adequate and consists of anti-inflammatory medications (e.g. ibuprofen or steroids).
What is Truncus Arterious?
Normally there are two main blood vessels leaving the heart: the aorta carrying blood to the body and the pulmonary artery that branches immediately to carry blood to each lung.
Instead of having a separate pulmonary artery and aorta, each with their own three-leafed valves, a baby with truncus arteriosus has only one great blood vessel or trunk leaving the heart, which then branches into blood vessels that go to the lungs and the body.
This great vessel usually has one large valve which may have between two and five leaflets. Usually this great vessel sits over both the left and right ventricle. The upper portion of the wall between these two chambers is missing resulting in what is known as a ventricular septal defect (VSD). In rare cases, the ventricular septal defect is absent.
Truncus arteriosus signs and symptoms
A baby with truncus arteriosus usually begins to have problems in the first week of life. Their oxygen levels are often slightly lower than normal resulting in cyanosis.
Because of the excessive amount of blood flow to the lungs with this anomaly, congestive heart failure (CHF) develops in the first week or two of life. On chest X-ray, the heart looks big and the lung fields look hazy indicating pulmonary overcirculation.
Signs of congestive heart failure are rapid breathing, shortness of breath, wheezing, grunting or very noisy breathing, nasal flaring, retractions, and restlessness.
The liver may be large due to a backup of blood or systemic congestion. Neck vein distention, poor feeding, and facial swelling are also seen.
Most often parents report rapid breathing, poor feeding, and a bluish color of the skin, especially around the mouth and nose. The signs and symptoms often increase when the infant eats.
Truncus arteriosus diagnosis
While the diagnosis may be suspected by physical examination, the echocardiogram will confirm the presence of truncus arteriosus. The anatomy of the great vessels, the single, complex truncal valve and the ventricular septal defect are easily seen.
A cardiac catheterization may be done on rare occasions if anatomy appears very unusual, or the diagnosis is made later as information is needed regarding the pressures in the pulmonary arteries. In most cases, however, the echocardiogram gives enough information to plan for surgery.
Treating truncus arteriosus
Initial treatment begins with stabilizing the infant. Medications to control congestive heart failure such as diuretics are often begun.
Ensuring good nutrition may require the use of a feeding tube or intravenous hyperalimentation. Surgical correction is typically carried out in the first few weeks of life after the infant is maximally stabilized.
The surgical repair of truncus arteriosus requires the use of heart-lung bypass machine support. It involves three major components:
Separating the pulmonary arteries from the main truncus (the truncus will remain as the first part of the aorta);
closure of the ventricular septal defect using a patch
creating a connection between the right ventricle and the pulmonary arteries using a valved conduit, usually a homograft pulmonary artery.
Most infants will require a period of very close monitoring in the Cardiac Intensive Care Unit while their heart function recovers from the major reconstruction.
The use of mechanical ventilation, special monitoring lines, and strong intravenous medications is typical during this period.
Gradually, as the heart function stabilizes, the supporting measures may be withdrawn and conversion to oral medications and attention to feeding dominates the management program.
Time in hospital following surgery may vary from one to three weeks in most cases.
Truncus arteriosus treatment results
Currently over 90 percent of children survive repair of truncus arteriosus. As the child grows, they will be followed by their cardiologist.
Typically, there will be no physical restrictions imposed on the child. As a child grows, the conduit that was used to connect the right ventricle and pulmonary arteries will not, and this will lead to obstruction to blood flow. The progression of this narrowing is easily followed by the cardiologist using physical examination and echocardiograms.
Recommendation for surgery to replace the right ventricle to pulmonary artery conduit with a larger one is usually made long before any symptoms would be evident.
This conduit will often need to be replaced two or three times during childhood to accommodate for growth. These operations are typically tolerated very well with a hospitalization of less than a week.
Problems with the truncal valve are more serious and can significantly affect the early and late mortality of these children. The more leaky (or narrowed) this valve is, the greater the chance that some intervention has to be done sooner than later (on average within 5 to 7 years) to prevent severe damage to the heart.
Delayed Sternal Closure
On occasion after an open-heart procedure, the child’s hemodynamics may be tenuous. Added to that, not infrequently there is some swelling of the heart muscle from surgery and the inflammation induced by the heart-lung machine.
For that reason, at times surgeons elect to leave the chest open only to close it a few days later. In this way, the breastbone is prevented from pushing on the heart in the most critical and early hours after an operation. Despite this, the heart itself is not exposed; a layer of soft protective material is sewn to the skin edges to provide coverage of the heart, along with sterile bandages.
To minimize the slightly increased risk of infection, antibiotics are continued during the time the chest is open. Generally, the chest is closed in the intensive care unit under the same heavy sedation and analgesia that is provided to the infant during this time.
Intraaortic Balloon Pump
The intraaortic balloon pump (IABP) is a device used in some critically ill patients to help reduce the work of the failing heart. The IABP is sometimes used during cardiac surgery to help remove the patient from the heart-lung bypass machine. It is sometimes used to help the heart of severely ill patient who is awaiting a cardiac transplant. At times it is used for a patient suffering from cardiogenic shock, a condition when the heart cannot pump well enough to keep adequate blood pressures.
The IABP is a long tube (catheter) with a collapsed, 8-inch, sausage-shaped plastic balloon at its tip. The catheter is inserted in an artery in the groin. The doctor directs the tube through the artery and positions it in the aorta. A pump is attached to the hub end of the catheter. The balloon is rapidly inflated and deflated using the heartbeat as a trigger. The end result is increased blood flow to the body at less cost to the heart.
Since blood clots can form around the catheter, blood thinners (anticoagulants) must be used after inserting the IABP. These clots can dislodge and embolize to other parts of circulation, causing blockage of arteries or even stroke. Although IABP can be used for weeks, when the catheter is left in for more than a few days, there is risk of infection. The IABP itself is rarely the cause of death. The disease requiring its use is usually responsible.
Left Ventricular Assist Device (LVAD)
A left ventricular assist device (LVAD) is a mechanical pump that helps a weakened heart pump blood throughout the body. It is typically used as a "bridge-to-transplant", but on occasion it is used in place of ECMO support, while the heart recovers. More recently, at some centers the LVAD device is being provided as an alternative to transplant or "destination therapy."
These devices are mostly geared toward adults, although some recent progress has been made in developing LVAD support for children. Often in the pediatric setting LVAD is used in the place of ECMO when the problem is strictly limited to the left side of the heart and the lungs appear to be fine. Although a right ventricular assist device (RVAD) can also be implemented when the right side of the heart is failing, generally ECMO support is preferred in that setting.
There are a variety of LVAD devices, but the one used most commonly in the pediatric setting is called the Biomedicus pump. Risk of bleeding and the need for anticoagulation (and therefore the need for transfusion of blood products) may be less with LVAD than ECMO.
Post-Pericardiotomy Syndrome (PPS)
Post-pericardiotomy syndrome is a condition that develops in about 2 to 15% of patients after open heart surgery. In this condition, the patient typically develops chest discomfort, fever and evidence of "inflammation" on blood tests. Although the etiology is unknown, it is believed to be some kind of immunologic reaction to the heart and pericardium as consequence of surgery.
The condition often occurs 1 to 2 weeks after open heart surgery and is associated with developing a pericardial effusion (fluid around the heart). An echocardiogram and EKG are performed and treatment is initiated based on signs and symptoms and the size of the pericardial effusion. If the fluid collection is large enough to be compromising heart function, the doctors may recommend tapping and removing the fluid under ultrasound guidance. Otherwise medical therapy is often adequate and consists of anti-inflammatory medications (e.g. ibuprofen or steroids).
Hypoplastic Right Heart Syndrome
Hypoplastic Right Heart Syndrome
Hypoplastic right heart syndrome (HRHS) refers to underdevelopment of the right sided structures of the heart. These defects cause inadequate blood flow to the lungs and thus, a blue or cyanotic infant. The major problem is pulmonary valve atresia (absence). This valve normally opens and closes to let blood flow to the pulmonary artery. Secondary problems include a very small (hypoplastic) right ventricle (lower chamber which normally pumps blood to the lungs); a small tricuspid valve (this valve allows blood to flow into the right ventricle) and a small (hypoplastic) pulmonary artery. Also, the blood flow into the coronary arteries may be abnormal causing damage to the heart muscle.
The infant is born with two connections that help blood flow. These are a foramen ovale (hole between the atria) and patent ductus arteriosus (or PDA, a blood vessel between the aorta and pulmonary artery). As these connections begin to close, the infant becomes critically ill.
Because the blue blood cannot pass through the right side of the heart to get to the lungs, it crosses into the left atrium and mixes with red blood returning from the lungs. This mixed blood is pumped out of the aorta. The only way in which blood gets to the lungs is through the PDA. The PDA must be maintained open with medicine (PGE1). Surgery is usually performed shortly after starting PGE1 to create an artificial connection (shunt) between the aorta and the pulmonary artery to deliver blood to the lungs.
Hypoplastic right heart syndrome (HRHS) refers to underdevelopment of the right sided structures of the heart. These defects cause inadequate blood flow to the lungs and thus, a blue or cyanotic infant. The major problem is pulmonary valve atresia (absence). This valve normally opens and closes to let blood flow to the pulmonary artery. Secondary problems include a very small (hypoplastic) right ventricle (lower chamber which normally pumps blood to the lungs); a small tricuspid valve (this valve allows blood to flow into the right ventricle) and a small (hypoplastic) pulmonary artery. Also, the blood flow into the coronary arteries may be abnormal causing damage to the heart muscle.
The infant is born with two connections that help blood flow. These are a foramen ovale (hole between the atria) and patent ductus arteriosus (or PDA, a blood vessel between the aorta and pulmonary artery). As these connections begin to close, the infant becomes critically ill.
Because the blue blood cannot pass through the right side of the heart to get to the lungs, it crosses into the left atrium and mixes with red blood returning from the lungs. This mixed blood is pumped out of the aorta. The only way in which blood gets to the lungs is through the PDA. The PDA must be maintained open with medicine (PGE1). Surgery is usually performed shortly after starting PGE1 to create an artificial connection (shunt) between the aorta and the pulmonary artery to deliver blood to the lungs.
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