A congenital heart defect is a malformation of the heart that is present at birth. Some congenital heart defects are very minor and will never cause health problems. Others are very serious and complicated. These defects are usually discovered in infancy or early childhood due to symptoms and may be surgically repaired at that time.
Adult congenital heart disease normally takes one of two forms: a defect with no symptoms early in life that becomes associated with symptoms later on, or a complex defect repaired during childhood that requires further repair or new treatment in adulthood. Because repaired congenital heart defects can still cause problems later on, patients with a defect repaired in childhood need regular follow-up cardiac care throughout their lives. Occasionally, an adult will experience symptoms of a more complicated defect for the first time as an adult.
The Adult Congenital Heart Clinic at the University of Ottawa Heart Institute takes over the care of patients with congenital heart defects once they become adults.
The most common types of minor congenital heart defects diagnosed in adults are:
Septal Defects (“holes in the heart”)
A septal defect (see illustration) can occur between the two ventricles (pumping chambers) of the heart, called a ventricular septal defect, or between the two atria (filling chambers), called an atrial septal defect. With either type, oxygenated blood coming from the lungs gets mixed with deoxygenated blood returning from the body. A serious complication of septal defects is seen when the direction of the mixing of blood causes the blood supply leaving the heart to contain less oxygen than normal (a shunt, or “septal hole,” that is right to left). A shunt, whether left to right or right to left, makes the heart work harder to distribute the same amount of oxygen to the body.
A valve in the heart may be unable to open completely or unable to close completely due to a defect, or may be misshapen. These defects force the heart to work harder to move a normal volume of blood through the heart in meeting the demands of the body.
Narrow Blood Vessels
Blood vessels that are too narrow at a certain point cause the heart to work harder to pump a normal supply of blood. Blood vessels can be connected incorrectly, sending deoxygenated blood to the body or already oxygenated blood back to the lungs.
A congenital heart defect is a condition one is born with. Some genetic (inherited) diseases or disorders, such as Down's syndrome, are associated with congenital heart defects. Some substances or diseases that a pregnant woman is exposed to can cause a congenital heart defect in her unborn child, including some prescription medications, rubella (German measles), and uncontrolled diabetes.
Common symptoms of adult congenital heart defects include:
- Shortness of breath, especially during exercise
- Cyanosis (a blue tint to the lips, skin, or fingernails caused by a lack of oxygen)
- A heart murmur
- Abnormal heart rhythms (arrhythmias)
- Swelling of the extremities
Many of these symptoms can be confused with other diseases affecting the heart or lungs and less serious conditions, as well as with the effects of aging and physical inactivity.
Tests commonly used to diagnose adult congenital heart defects include:
- Echocardiogram: to determine the anatomical structure of the heart as well as the volume of blood pumped by the heart and the pressures within the heart
- Electrocardiogram: to identify problems with heart rhythm
- Chest X-rays: to look at the size and shape of the heart
- Coronary catheterization: to identify blocked or restricted blood vessels
- Magnetic resonance imaging (MRI): to take detailed pictures of the heart's chambers and blood vessels
- Stress (exercise) testing: to measure how well the heart functions when challenged to work harder than normal
A variety of approaches can be taken in treating and managing a congenital heart defect depending on the type and severity of the defect.
Some minor congenital heart defects discovered in adults will never need to be treated or repaired. However, these patients should receive regular cardiac checkups to make sure that the defect does not deteriorate over time.
Some minor congenital heart defects can be treated with drugs to help the heart work better. These include drugs to:
- Slow the heartbeat (beta blockers)
- Help relax the blood vessels (calcium channel blockers)
- Help prevent blood clots, such as warfarin
- Remove excess fluid in the body (diuretics)
Not all drugs work for all types of congenital heart defects. Some drugs that work for one type of defect can actually make other types worse.
Many patients with a congenital heart defect are at risk for an infection of the heart, especially a condition called endocarditis, even if their defect has been repaired. Some patients need to take antibiotics before any dental or surgical procedure to reduce the risk of a life-threatening infection. Ask your doctor whether you need to take antibiotics.
Some congenital heart defects discovered during adulthood will need to be repaired surgically. For many of these, the surgery can be performed through a catheter-a tube that is run through a blood vessel to the heart. Catheter techniques can be used to repair small septal defects and some defective valves. Catheter techniques are also employed in balloon angioplasty or to place a stent to open a blood vessel or valve. Some small adjustments to repairs performed in childhood can also be done using a catheter.
Valve replacement and the repair of more complicated congenital heart defects can be done through open-heart surgery.
Although it is rare, a patient with a life-threatening congenital heart defect may receive a heart transplant or a heart-lung transplant. These procedures are performed only in patients who are healthy enough to undergo major surgery.
- Canadian Congenital Heart Alliance
Organization supporting Canadians living with congenital heart disease
- Canadian Adult Congenital Heart Network
Canadian website presenting information for patients, their families, and physicians
- The Nevil Thomas Adult Congenital Heart Library
Canadian website providing access to multimedia learning resources on the subject of congenital heart defects in the adolescent and adult