Common Types of Pediatric Congenital Heart Defects
Septal defects
A septal defect means that blood flows from one chamber of the heart to
the other, instead of taking its normal path. For instance, with an
atrial septal defect, blood flows from one atrium to the other, instead
of going to the ventricle.
Similarly, with a VSD, the blood flows from the left ventricle to the
right ventricle, rather than through its normal path to the aorta and
the rest of the body. As a result, blood that has picked up oxygen from
the lungs mixes with oxygen-poor blood. This can mean that parts of the
body aren’t getting enough oxygenated blood.
ASDs and VSDs can be small or large. Some ASDs close up on their own as
the child grows older. Others may be repaired using catheters or with
open heart surgery.
Although some small VSDs may close on their own, some are so large that
the left side of the heart is forced to work much harder. If it is not
treated, a VSD can lead to heart failure. These defects have to be
repaired with open heart surgery.
Valve defects
Another type of defect involves the heart valves. Defective valves may be caused by:
- Stenosis (narrowing) — the valve is not able to open completely. As a result, the heart has to work harder to pump blood through it.
- Regurgitation — The valve does not close correctly and allows blood to leak backward.
- Atresia — the valve is missing a hole for the blood to pass through. This is considered a more complex defect.
Pulmonary valve stenosis is the most common valve defect. In this
defect, the flaps of the pulmonary valve don’t work properly—they are
too thick, or they become stiff, or even fuse together, making it
difficult for the blood to move to the lung via the pulmonary artery.
Children who have a pulmonary valve stenosis may have a heart murmur, an
irregular sound heard during a heartbeat. Children who are born with a
severe pulmonary valve stenosis may have such symptoms as fatigue,
breathing problems, and trouble eating.
Pulmonary valve stenosis may also be accompanied by other defects, such
as an ASD or patent ductus arteriosis (PDA). The ductus arteriosis is a
blood vessel in the fetus that connects the aorta and the pulmonary
artery. The ductus arteriosis usually closes within minutes or days of
birth; if it does not close, it is called a patent (open) ductus
arteriosis (PDA).
A PDA lets oxygenated blood and deoxygenated blood mix and puts pressure
on lung arteries. In the event of certain heart defects, doctors might
choose to keep the PDA open until surgery to correct other blood flow
defects can be done.
Stenosis can also affect the aortic valve. If this valve cannot open or
close properly, blood may leak or pool. This can increase pressure on
the heart and cause heart damage. A balloon catheter procedure might be
performed in order to widen the valve and increase the blood flow.
Other types of congenital heart defects
- Coarctation of the aorta — This defect happens when the aorta narrows and prevents blood from flowing freely to the lower part of the body. Coarctation of the aorta can cause hypertension (high blood pressure) and heart damage. Surgery or balloon catheterization in selected cases can be used to correct this problem.
- Complete atrioventricular canal defect (CAVC) — The heart has a hole in all four chambers in the spot where the chambers would normally be divided. Symptoms may not appear until the baby is several weeks old; infants may have trouble breathing, eating, and growing. This defect can be corrected with surgery.
- D-transposition of the great arteries — The positions of the pulmonary artery and the aorta are reversed. The blood flow to either the body or the lungs is interrupted. Surgery is needed to fix this problem.
- Ebstein’s anomaly — The tricuspid valve does not work as it should and allows blood to leak back into the upper chambers of the heart from the lower pumping chambers. This defect often occurs along with an ASD. Ebstein’s anomaly may be mild enough to never require surgery. In some cases, however, it may cause cyanosis (the skin turns blue because of a lack of oxygen) or heart failure.
- Single ventricle defects — These include hypoplastic left heart syndrome, pulmonary atresia/intact ventricular septum, and tricuspid atresia:
- In hypoplastic left heart syndrome, the left side of the heart is underdeveloped. Without treatment, the baby will usually die. Treatment might include a series of heart operations or a heart transplant.
- In pulmonary atresia, the pulmonary valve has become narrowed or blocked. Blood can only get to the lungs through openings that usually close as the baby gets older.
- In tricuspid atresia, there is no tricuspid valve. Blood has to circulate through an ASD. Surgery is necessary to repair these defects.
- Tetralogy of Fallot — This defect combines four problems: a ventricular septal defect; pulmonary stenosis (a blockage between the heart and the lungs); right ventricular hypertrophy (the muscle around the lower right chamber of the heart is enlarged); and the aorta is in the wrong position (over both ventricles, instead of just the left ventricle). Surgery is needed to correct this defect.
- Total anomalous pulmonary venous connection — The veins from the lungs connect to the heart in the wrong place and let oxygenated blood into the wrong heart chamber. This defect requires open heart surgery early in infancy.
- Truncus arteriosis — This defect occurs when there is one large artery instead of the usual two separate ones to carry blood to the body and the lungs. Surgery is needed to close the VSD and to add another tube to act as the second artery.
What are the symptoms of pediatric congenital heart disease?
Often, there are no symptoms associated with these defects. The defects
are usually found during routine physical examinations. In cases where
there are symptoms, they may include:
- Trouble breathing
- Bluish tones to the skin (cyanosis)
- Poor eating habits
- Fatigue (tiredness)
- Swelling in the abdomen or around the eyes
- Rapid heartbeat
How are pediatric congenital heart defects diagnosed?
Tests to diagnose heart defects might include:
- Physical examination, including listening to the heart with a stethoscope
- Chest X-ray
- Electrocardiogram to test heart rate patterns
- Echocardiogram (takes pictures of the heart using sound waves)
- Cardiac catheterization (a thin tube is inserted through a vein into the heart to obtain details on heart function)
Some defects can be diagnosed while the baby is still developing in the womb.
What causes pediatric congenital heart defects?
In most cases, the reasons defects happen are not known, but some connections have been identified:
- Women who get German measles (rubella) during their first trimester of pregnancy have a higher risk of having a baby with a congenital heart defect.
- The risk may also be higher if the woman has some types of viral infections, is exposed to industrial solvents, takes certain kinds of medications, drinks alcohol, or uses cocaine while pregnant.
- Women who have given birth to a child with a congenital heart defect are at higher risk of giving birth to another child with a heart defect.
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