Ventricular Septal Defect

A Ventricular Septal Defect is also known as a VSD or “hole in the heart”. It is a type of congenital heart defect, which means it was present at the time of birth. It can be an isolated defect or can be associated with other cardiac defects. The abnormal opening or “hole” is in the septum between the two lower chambers of the heart called ventricles. The defect can vary in size from pinhole to a complete absence of the septum resulting in a common ventricle. Because of this opening, blood can flow from the oxygen-rich left ventricle to the oxygen-poor right ventricle. The blood is mixed and goes back out to the lungs to pick up more oxygen. Because too much blood is trying to get into the lungs, sometimes it gets pushed back into the right ventricle and this can result in an enlarged right ventricle. This increased blood flow makes a “whooshing” sound, called a murmur. It can be heard by listening with a stethoscope.

Causes

A congenital defect occurs during fetal development. The heart is developed during the 5th week of pregnancy. VSD is the most common congenital cardiac malformation. Sometimes, birth defects can be caused by exposure to a poison in the environment, an infection, uncontrolled diabetes, alcohol or drug abuse, or chromosomal abnormalities (extra or missing pieces of genetic material). But most of the time, the cause of a congenital heart defect is simply unknown.

Signs/Symptoms

The size of the defect and its location along the septum determines the symptoms. The defect can be located in the membrane or the muscle. Kids with small defects often have no symptoms and those VSDs will usually close on their own. Babies with moderate to large VSDs may show symptoms such as:

  • Faster breathing
  • Tiring easily with feeds
  • Sweating or crying, especially with feeds
  • Slow weight gain

These types of symptoms often mean that the defect is not closing on its own and cardiac surgery may be needed. It is common for this type of surgery to be done within the first 3 months of life so that further complications can be prevented. However, a cardiologist may prescribe certain medications to lessen some of the symptoms so the baby can grow and be the healthy before having surgery.

Diagnosis

A murmur is often noted on a routine physical exam by the child’s pediatrician. The doctor should refer the patient to a pediatric cardiologist (a doctor who is a specialist in diagnosing and treating childhood heart conditions & diseases) for further evaluation. In addition to performing a complete exam and taking a full history, the cardiologist will most likely order a variety of tests such as:

  • Chest X-ray (CXR) – shows the heart, lungs and surrounding organs.
  • Electrocardiogram (EKG) – records the electrical activity of the heart and shows if the right side of the heart is enlarged due to increased blood flow.
  • Echocardiogram (Echo) – similar to an ultrasound; uses sound waves to bounce off the structures of the heart and produces a picture of the heart; shows the volume and direction of flow through the heart itself. This is generally the gold standard for diagnosis of a VSD.
  • Cardiac Catheterization (Heart Cath) – performed only if further information is needed; provides information about the heart’s structures, blood pressure & oxygen levels within the heart itself.

Treatment

Treatment of a VSD depends upon the age and size of the child as well as the location and severity of the defect. A cardiologist will regularly follow a patient with small defects who are asymptomatic to be sure that there are no concerns. Most of the time, a small defect will close on its own without surgery. If it remains open and doesn’t get any larger or cause problems, these kids will usually not have to restrict their physical activities.

If surgical correction is necessary, there are several options.

  1. Pulmonary artery banding: In infants, a band can be placed around the pulmonary artery to restrict the flow of blood into the lungs. This is sometimes done if there are multiple VSDs or more complex anatomy, and it is only palliative (a temporary “fix” to prevent damage to the lungs). A more corrective surgery will be needed once the baby grows.

  2. Complete repair: Open heart surgery is the procedure of choice. A cardio-thoracic surgeon will make an incision in the center of the chest (sternum) to expose the heart. The patient will be on a heart-lung bypass machine for a short period of time while the surgeon is performing the repair. Small defects are repaired by stitching the defect closed. For larger defects, a patch of knitted Dacron is sewn over the opening. The tissue of the heart will grow over the stitches or patch within about 6 months. The child will spend several days in the hospital, first in the cardiac ICU, then on a special cardiac unit where the doctors, nurses, and other staff will closely monitor for arrhythmias, breathing concerns, infection or poor eating. Generally, the younger the child is, the less pain they have during the recovery period. This is mainly because the sternum in infants and younger children is more pliable.

    These kids will have activity restrictions for 6 weeks post-op to prevent injury to the sternum. The parent will be instructed on Systemic Bacterial Endocarditis (SBE) Prophylaxis. This means that the child should have antibiotics before any routine dental work or surgical procedure to prevent an infection on the inside of the heart from occurring. The risk of this usually diminishes after 6 months. All risks and complications are discussed prior to a cath procedure or heart surgery.

  3. Cardiac Catheterization: Some of the smaller VSDs may be closed in the cath lab. This is being done in some facilities under investigational protocols. A catheter (a thin, flexible tube) is inserted into a blood vessel in the groin. It is threaded up into the heart to where the hole is located. A special implant made of flexible mesh is positioned over the hole to cover and seal the defect permanently from both sides. The patient’s own tissue grows over the mesh and completely covers it in about 6 months. This procedure usually requires only an overnight hospital stay. These patients will need to take a low-dose of aspirin for 6 months because of a small risk of clots forming on the device until the tissue grows over it. The child shouldn’t have a sit-down tub bath or swim for 3 days following the procedure, and they are usually kept out of gym class or sports for approximately one week or until cleared by their doctor. These kids should also have regular follow-ups with their cardiologist.

Prognosis

Most kids who have had a VSD repair recovery quickly and without further problems. Doctors will continue to monitor them regularly for any changes or concerns in their overall health. These kids generally have a normal life expectancy and go on to lead active and healthy lives.

DORV

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Atrial Septal Defect

An Atrial Septal Defect is also known as an ASD or a “hole in the heart”. It is a type of congenital heart defect, which means it was present at the time of birth. The abnormal opening or “hole” is in the septum (dividing wall) between the two upper chambers of the heart. These upper chambers are called atria. Because of this opening, blood is able to flow from the left atrium to the right atrium. Since pressure in the left side of the heart is higher and since the blood on the left side of the heart is oxygenated, this particular defect allows oxygen-rich blood to be pushed over to the oxygen-poor right side, resulting in too much blood being sent to the lungs. This increase in blood flow makes a “whooshing” sound called a heart murmur.

Causes

A congenital defect occurs during fetal development. The heart is developed during the 5th week of pregnancy. Most of the time, there is no clear cause as to why this happens. ASDs account for 7-10% of all cardiac defects, and 40-50% of them can spontaneously close by the age of 2 years. It is also possible that other genetic syndromes or more complicated cardiac defects can include an ASD.

Signs/Symptoms

This defect is commonly detected in childhood, but may also be found in infancy. These children may have no symptoms at all, and in fact, they may grow and develop normally. However, depending on the size and location of the defect, they may have these signs or symptoms:

  • Poor appetite
  • Poor growth
  • Shortness of breath
  • Tires easily
  • Respiratory infections such as RSV or pneumonia.

If kids with more severe ASDs are not treated, they may develop further complications such as arrhythmias, heart failure, pulmonary hypertension (high blood pressure in the lungs themselves) or stroke. The older a child is, the more complications there may be. If a significant defect is detected at age 2 years or older, the ASD should be surgically closed between ages 2 and 4 years to prevent complications.

Diagnosis

A murmur is often noted on a routine physical exam by the child’s pediatrician. The doctor should refer the patient to a pediatric cardiologist (a doctor who is a specialist in diagnosing and treating childhood heart conditions & diseases) for further evaluation. Because a defect can range in size and location, if the defect is small enough, a murmur may not actually be detected until adolescence or even into adulthood.

Diagnostic Tests

  • Chest X-ray (CXR) – shows the heart, lungs and surrounding organs.
  • Electrocardiogram (EKG) – records the electrical activity of the heart and shows if the right side of the heart is enlarged due to increased blood flow.
  • Echocardiogram (Echo) – similar to an ultrasound; uses sound waves to bounce off the structures of the heart and produces a picture of the heart; shows the volume and direction of flow through the heart itself. This is generally the gold standard for diagnosis of an ASD.

Treatment

There is no specific medical treatment appropriate for this defect. A cardiologist will follow a patient, especially those with small defects, with regular office visits to monitor growth and any other concerns. There is usually no physical activity restriction for these children.

If surgical correction is necessary, many small to moderate defects can be treated in the cardiac catheterization (cath) lab rather than have open heart surgery. This method is preferred since it is much less invasive. In the cath lab, a catheter (a thin, flexible tube) is inserted into a blood vessel in the groin. It is threaded up into the heart, passed through the hole in the heart, and device is deployed. The most common occlusive device is called an Amplatzer Septal Occluder. It resembles a 2-sided umbrella and it covers and seals the defect permanently from both sides. The patient’s own tissue grows over the device and completely covers it in about 6 months. This procedure usually requires only an overnight hospital stay. These patients will need to take a low-dose of aspirin for 6 months because of a small risk of clots forming on the device until the tissue grows over it. The child shouldn’t have a sit-down tub bath or swim for 3 days following the procedure, and they are usually kept out of gym class or sports for approximately one week or until cleared by their doctor. These kids should also have regular follow-ups with their cardiologist.

If open heart surgery is required, a cardio-thoracic surgeon will make an incision in the center of the chest (sternum) to expose the heart. The patient will be on a heart-lung bypass machine for a short period of time while the surgeon is performing the repair. This can be done either by stitching the defect closed or using a patch of special surgical material if the defect is too large to stitch. The tissue of the heart will grow over the stitches or patch within about 6 months. The child will spend several days in the hospital, first in the cardiac ICU, then on a special cardiac unit where the doctors, nurses, and other staff will closely monitor for arrhythmias, breathing concerns, infection or poor eating. Generally, the younger the child is, the less pain they have during the recovery period. This is mainly because the sternum in infants and younger children is more pliable.

The child will have activity restrictions for 6 weeks post-op to prevent injury to the sternum. The parent will be instructed on Systemic Bacterial Endocarditis (SBE) Prophylaxis. This means that the child should have antibiotics before any routine dental work or surgical procedure to prevent an infection on the inside of the heart from occurring. The risk of this is usually diminished after 6 months. All risks and complications will be discussed prior to either a cath procedure or open heart surgery.

Prognosis

After ASD closure, it is common for parents to notice that their child has an increase in exercise endurance and growth. These children have a favorable outlook and go on to live normal, active lives.

Aortic Stenosis

Aortic Stenosis is a condition that causes a blockage in the flow of blood between the left ventricle and the aorta. The obstruction can be below the aortic valve, at the valve itself, or just above the valve. The most common type of aortic stenosis is obstruction at the valve itself.

Anatomy/Causes

It is important to describe a normal valve first. The normal aortic valve has three thin, flexible leaflets. When the left ventricle pumps blood into the aorta to go out to the rest of the body, the normal aortic valve leaflets spread apart easily and cause no obstruction to the flow of blood out of the heart. In aortic stenosis, the leaflets of the valve are not formed correctly. The most common defect is when the valve has only two leaflets instead of three. This is called a bicuspid valve. It is a congenital defect. These two leaflets are often thickened and not as flexible as they should be. This causes the left ventricle of the heart to work harder to push the blood out of the aorta to the rest of the body. This extra work put on the left ventricle causes the muscle tissue of the left ventricle to get thicker. This is called left ventricular hypertrophy or LVH. If the obstruction of the aortic valve is severe, the left ventricle may not be able to work hard enough and it begins to fail. Fortunately, this is rare, but when it happens, the child goes into heart failure.

Signs/Symptoms

Kids with this defect are often healthy and have no symptoms. The most common indication that there is a problem is when a pediatrician hears a murmur, a “whooshing” sound heard with a stethoscope. If the stenosis is mild to moderate, a murmur will be heard easily. Later in childhood, kids may develop exercise intolerance, labored breathing and fainting upon exertion. If the stenosis is severe, it is an emergent situation. This happens in a newborn on the first day of life and requires immediate treatment since the infant is in heart failure. Older children rarely experience heart failure, but they may have chest pain, fainting spells or dizziness, especially when they exercise. An older child with undiagnosed severe aortic stenosis is at high risk of sudden death during strenuous activities such as sports.

Diagnostic Tests

  • Electrocardiogram (EKG) – records the electrical activity of the heart. It is usually normal in mild to moderate stenosis. If there is severe stenosis, it can show left ventricular enlargement.
  • Echocardiogram (Echo) – similar to an ultrasound; uses sound waves to bounce off the structures of the heart and produces a picture of the heart; shows the volume and direction of flow through the heart itself. It can accurately show the obstruction itself and how severe it is. This is the gold standard for diagnosis of aortic stenosis.
  • Stress Test – Attached to monitors and in the presence of a physician, the child runs on a treadmill while being closely observed for abnormal blood pressure and heart function in response to exercise. The results may help the doctor decide if treatment is needed.
  • Cardiac Catheterization (Heart Cath) – provides information about the heart’s structures, pressure measurements above and below the valve to determine the degree of valve obstruction, and oxygen levels within the heart itself.

Treatment

In kids with mild aortic stenosis, treatment is rarely required. Unfortunately, this can be progressive over time and these kids may eventually require treatment. Therefore, it is important that they be followed closely by a cardiologist.

Treatment itself is determined by the degree of stenosis and its location. For mild valvular stenosis, kids are typically managed with diuretics, antibiotics (to prevent infection in the heart) before any routine dental or surgical procedure, and exercise restriction.

Moderate to severe aortic stenosis requires intervention. Balloon dilation valvuloplasty, performed in the Cath Lab, is the first-line procedure. This is not open heart surgery, is done via the femoral artery in the groin, and generally requires only an overnight stay in the hospital. It can also be done as an outpatient in older children. If open heart surgery is necessary, the surgeon will perform a valvotomy where the stiff and malformed valve is opened. This is only done when the valve cannot be improved with simple balloon dilation. In some more complicated valve issues, the aortic valve may need to be completely replaced. This is called a Ross Procedure and with it, the patient’s own pulmonary valve is transplanted to the aortic valve position. The pulmonary valve is then replaced with a homograft (human donor graft) from the right ventricle to the pulmonary artery. This is a wonderful option for younger children since the newly replaced aortic valve can continue to grow with the child. This prevents more frequent surgeries to replace a valve that the child has outgrown and also does not require that the child take blood thinner medication. However, it will require eventual replacement of the pulmonary valve homograft.

There is another surgical procedure that may be necessary if the aortic valve is too small. The Konno procedure is a technique to enlarge the area where a new valve needs to be placed. This new valve is called a “mechanical valve” because it is not made from the patient’s own tissue. This will require that the patient be on blood thinner medication along with regular blood tests to monitor blood levels of the medication, usually Coumadin. A mechanical “click” sound of this valve can be heard with a stethoscope.

Prognosis

Balloon dilation valvuloplasty has shown excellent results, even though it causes mild valve insufficiency or leakage. This generally does not cause problems; however, recurrent narrowing does occur in many children within the next 5-10 years after the procedure. Many of these children will require repeat balloon dilation or surgical valve replacement.

Results of these open heart surgical procedures have also been excellent as they relieve all aortic stenosis with low complication rates. If an adult-sized artificial aortic valve is implanted in larger children or adolescents, they should see excellent function for 20 years or more. If the replacement of the valve is done as a younger child, the concern is that the child will outgrow the size of the artificial valve, and repeat surgical replacement will be needed in later years.

All treatments for aortic stenosis are palliative not a cure. Long-term follow-up with a cardiologist is essential for helping to provide the best outcome for these patients.