Congenital Heart Defects

Birth defects can affect many systems of the body, including the heart. As a group, these birth defects are sometimes called "congenital heart defects."

The heart is a complex organ made up of many parts working in concert. Congenital defects that affect the heart can involve any of the heart's structures, including the four chambers, valves, the musculature and the blood vessels. In addition, a heart defect can cause problems in structure, function or both. Some genetic syndromes can include a heart defect as a symptom; however, the cause of most congenital heart defects is unknown.

The Human Heart

The heart is composed of four chambers:

• Left atrium
• Left ventricle
• Right atrium
• Right ventricle.

The left atrium receives oxygenated blood from the lungs. It is then pumped into the left ventricle, which pumps this blood to the rest of the body via the aorta. Deoxygenated blood is pumped from the body back into the right atrium, and then travels into the right ventricle. The right ventricle then pumps this blood into the lungs, where it can be saturated with oxygen and pumped back into the heart to begin the process anew.

Heart Defect Types

In the heart, congenital defects can affect any of the organ's four chambers, as well as the valves and blood vessels by which the blood travels from one chamber to another, or from the heart to and from the body. Common congenital heart defects include:

• Aortic/pulmonary valve stenosis
• Hypoplastic left heart syndrome
• Tetralogy of fallot
• Transposition of the great arteries.

Heart Defect Diagnosis

Doctors use many different tests to examine the heart and diagnose a heart defect. In the heart, congenital defects may be found using the following:

• Cardiac catheterization involves threading a tube up through a blood vessel and into the heart. This procedure is more invasive than others, but can be used to diagnose and even treat some congenital heart defects.
• Chest x-rays useelectromagnetic waves and ionizing radiation to capture an image of the heart, resulting in minimal radiation exposure.
• Echocardiograms/ultrasounds use sound waves to find structural and functional heart defects. These tests can also be performed in utero in order to identify congenital defects before a baby is born. An echocardiogram is the primary tool used to diagnose congenital heart defects.
• Electrocardiograms measure the heart's activity and can detect irregular heart rhythm.
• MRIs (magnetic resonance imaging) use magnets and radio waves and can provide both still (MRI) and moving (fMRI) images of the heart.

Tests performed on fetuses, infants and young children are usually noninvasive and non-surgical whenever possible. Early detection, usually via fetal ultrasound, can help you to prepare for any surgery or other medical intervention that may treat the heart defect once your child is born.

If a heart defect is not diagnosed before birth, symptoms of possible heart problems may include:

• Bluish tinge to lips or nails (cyanosis)
• Difficulty breathing or feeding
• Failure to thrive
• Weak pulse.

If you see these symptoms in your infant, report them to your pediatrician immediately.

Resources

Kids Health. (n.d.). Congenital heart defects. Retrieved April 11, 2010, from: http://kidshealth.org/parent/medical/heart/congenital_heart_defects.html.

Medline Plus. (n.d.). Congenital heart defects.Retrieved April 11, 2010, from: http://www.nlm.nih.gov/medlineplus/congenitalheartdefects.html .

National Heart Lung and Blood Institute. (n.d.). Congenital heart defects.Retrieved April 11, 2010, from: http://www.nhlbi.nih.gov/health/dci/Diseases/chd/chd_what.html.