Congenital heart defects, which affect the structure of the heart and how it performs, are the most common form of birth defects. The Centers for Disease Control and Prevention estimates that around 40,000 babies are born with a congenital heart defect every year. Some of those babies will need medical treatments and others may just need regular visits with a cardiologist who specializes in congenital heart defects.
More than 1 million adults alive today have a congenital heart defect. All of them should be seen regularly by a congenital heart specialist, but only about 200,000 actually do. Others may not be aware they have a defect or that they need regular visits to a specialist.
A Look Inside a Healthy Heart
The heart is about the size of a person’s fist and contains four chambers or sections. The top two chambers are called the atria, and the bottom two chambers are called the ventricles. The chambers on the right side of the heart deliver blood to the lungs and the chambers on the left deliver oxygenated blood to the body. Blood is pumped through the chambers and past four heart valves that open and close to let blood through.
The blood flows through the body and heart in a specific pattern.
- Blood flows into the right atrium from our veins.
- The right atrium empties the blood from our veins across the tricuspid valve into the right ventricle.
- The right ventricle pumps the blood across the pulmonary valve into the pulmonary artery (which carries the blood to the lungs).
- The oxygenated blood then returns from the lungs to the left atrium.
- The left atrium empties oxygenated blood across the mitral valve into the left ventricle.
- The left ventricle pumps oxygenated blood across the aortic valve into the aorta.
- The aorta branches into all the arteries that deliver oxygen to our body.
- After giving up oxygen to the body, the blood returns to our heart through our veins, and the cycle repeats itself.
Types of Congenital Heart Defects
The development of the fetal heart is a complex process. Throughout that development, an abnormality can occur. This leads to different types of congenital heart defects. Some people have one defect, and others may have more than one or a complex defect. Some of the common types are:
- Aortic valve stenosis—The aortic valve doesn’t open properly, which can cause pressure to build up in the left ventricle. The most common form of congenital heart defect is bicuspid aortic valve.
- Ventricular septal defect—A hole in the wall that separates the two ventricles. This is the second most common heart defect.
- Atrial septal defect—A hole occurs in the septum, the tissue between the heart’s two atria, or upper chambers.
- Coarctation of the aorta—Part of the aorta narrows, which causes high blood pressure above the narrowing and low blood pressure below the narrowing.
- Complete atrioventricular canal defect—A large gap occurs in center of the heart where the heart’s chambers and valves would normally meet, called the crux of the heart. This gap creates a single valve where there should normally be the mitral valve and the tricuspid valve.
- Ebstein’s anomaly—A malformed tricuspid valve doesn’t close properly, allowing blood to leak from the right ventricle back into the right atrium.
- Hypoplastic left heart syndrome—The left side of the heart is small and underdeveloped; therefore the left ventricle is unable to pump enough blood with oxygen to the body.
- Patent ductus arteriosus—A blood vessel that is needed only in fetal life—to connect the aorta and the pulmonary artery—stays open.
- Pulmonary valve stenosis—The pulmonary valve doesn’t open all the way and blocks the path of blood flow to the lungs.
- Single ventricle defects—A category of many defects that result in having only one pumping chamber instead of two.
- Tetralogy of Fallot—A complicated heart defect with four parts: an abnormal hole between the ventricles, an aorta that sits over that hole, an obstructed path to the lungs, and a right ventricle with thickened muscles.
- Total anomalous pulmonary venous connection—The blood vessels carrying oxygen-rich blood from the lungs connect abnormally to the heart.
- Dextro-transposition of the great arteries (D-TGA)—The aorta arises abnormally from the right ventricle and the pulmonary artery arises abnormally from the left ventricle; as a result, blood with low oxygen gets pumped from the veins back into the arteries.
- Levo-transposition of the great arteries (L-TGA)—A defect in which the right ventricle pumps blood to the body instead of the lungs and the left ventricle pumps blood into the lungs instead of the body; since the right ventricle is not used to pump blood to the body, it eventually fails.
- Truncus arteriosus—A ventricular-septal defect is present, and the pulmonary arteries arise abnormally from the aorta.
Causes and Prevention of Congenital Heart Defects
Some forms of congenital heart defects are caused by genetic abnormalities, nutritional deficits, diabetes, obesity, or exposures during pregnancy, including exposure to alcohol, chemicals, heat, infection, medication and smoking. However, for most people, the cause is not identifiable.
Treatment for Congenital Heart Defects
There is no cure for congenital heart defects, although some minor ones resolve spontaneously. All patients require monitoring throughout their lives. Some defects require heart surgery, cardiac catheterizations or a heart transplant. Even after surgery or catheterization, new heart conditions can happen later in life, such as:
- Arrhythmia
- Cardiomyopathy, or weakness in the heart
- Leaking or blocked heart valves
- Congestive heart failure
- Increased risk for heart infections
- Increased risk for blood clots
Patients require lifelong care and regular checkups with a congenital heart provider, but many people with a heart defect can live a normal, healthy life.
Living with Congenital Heart Defects
The most important thing is to maintain ongoing care with a congenital cardiologist. Of course, it is also important to follow a heart-healthy lifestyle including safe physical activity, eating a balanced diet and avoiding smoking. Some more specific tips to keep in mind:
- Ask your doctor if you need to follow any physical activity restrictions.
- Double-check any over-the-counter medications or supplements with your provider or pharmacist.
- Have regular appointments with a congenital cardiologist.
- Keep up with prescribed medications.
- Get all recommended vaccinations.
- Learn as much about your defect as possible.
