Congenital Heart Disease

What is Congenital Heart Disease?

Congenital heart defects – the most common birth defect – include abnormal formation of heart valves, holes in the heart, obstruction of blood flow through the heart chambers and blood vessels, and abnormal formation of blood vessels taking blood to or from the heart.

Simple congenital heart defects have only a single problem in heart formation, such as a single hole in the heart (atrial septal defect or ventricular septal defect, or VSD) or a malformed valve. Nearly half of patients with congenital heart disease, however, have what are considered to be either moderate or complex forms of congenital heart disease.

These more complicated forms often include multiple malformations of the heart. For example, tetralogy of Fallot is a moderately complex defect that includes a hole in the heart (VSD), abnormal positioning of the aorta, and obstruction of blood flow to the lungs (usually with an abnormal heart valve) that results in an inability to pump enough oxygen-rich blood through the body. Highly complex lesions include defects in which there might be only one major pumping chamber or failure of one of the heart valves to form.

Several congenital heart defects are relatively simple to correct, such as atrial septal defect or a blocked valve or blood vessel. While surgeries to repair these conditions have been successfully performed for decades, newer catheter-based techniques can be used in many cases to correct these simple defects without requiring open-heart surgery. Likewise, catheter-based techniques, such as insertion of catheter-based valves, can be helpful in certain patients with moderate or complex defects.

Significant improvements in surgical techniques have allowed for more complex malformations to be treated, resulting in good survival and quality of life for the majority of patients, including patients who have one pumping chamber instead of two.

Such advances have transformed the lives of many people with congenital heart disease. Each year, about 20,000 young patients now survive into adulthood. However, for about half of these survivors, including those whose heart defects were repaired when they were infants or children, congenital heart disease remains a lifelong condition. Patients can be at elevated risk for arrhythmias, heart failure, stroke, or sudden death. Women who wish to have children can face complications during pregnancy and birth.

That’s why it’s extremely important for people with congenital heart disease to receive ongoing care from pediatric cardiologists throughout childhood and then transition to a skilled adult congenital heart disease clinic as they mature. In addition, adults who have symptoms of heart disease should always receive comprehensive evaluation. A thorough diagnostic workup occasionally reveals a congenital heart defect that was never diagnosed and did not cause problems until adulthood.

Types of Congenital Heart Disease

The many types of congenital heart conditions include:

• Aortic stenosis: An abnormal aortic valve that restricts blood flow from the left ventricle to the aorta
• Atrial septal defect: A hole in the septum (muscle wall) between the atria
• Coarctation of the aorta: A constriction in the aorta
• Ebstein anomaly: A rare heart defect in which parts of the tricuspid valve are abnormal
• Patent ductus arteriosus: A small vessel connecting the aorta to the pulmonary artery that does not close after birth
• Tetralogy of Fallot: A combination of four heart defects that can cause babies to have insufficient oxygen throughout their bodies
• Transposition of the great arteries: Reversed positions of the aorta and pulmonary artery, causing low blood oxygen
• Ventricular septal defect: One or more holes in the muscular wall that separates the left and right ventricles

Risk Factors for Congenital Heart Disease

Congenital heart defects seem to occur spontaneously during a critical time in pregnancy for reasons not yet understood. Researchers are working to identify genes that control the development of the heart, as well as genetic abnormalities that can predispose a child to develop congenital heart disease.

Genetic testing is now available for certain gene defects and can be useful for patients with specific types of congenital heart disease or families with a strong history of congenital heart disease.

The risk for congenital heart disease can also increase if a pregnant woman has measles or other viral infections, abuses alcohol, or is exposed to certain chemicals or medications early in her baby’s development. However, a definitive cause for most cases of congenital heart disease has not been established. Most patients are the only ones in their families with the condition.

Caring for Patients with Heart Conditions Present Since Birth

Congenital heart disease refers to a variety of structural heart defects that are present at birth. Thanks to major advances in surgical treatment, more than 90 percent of infants and children diagnosed with congenital heart disease now survive into adulthood, many of them reaching middle age and beyond.

Most adults with congenital heart disease don’t get the long-term follow-up care that’s recommended. Even when heart defects are surgically repaired during infancy or childhood, patients with congenital heart disease can experience recurring problems or develop complications years later. In addition, patients can be at higher risk for new heart problems as adults.