The most common types of birth defects involve the heart. In the U.S., more than 35,000 babies greet the world afflicted by congenital heart defects, affecting approximately eight out of every 1,000.
It’s unclear what causes most of these defects, but genetics seem often to play a part, as well as fetal exposure to adverse environmental conditions, such as if the mother smokes or takes certain types of medications. Defects tend to develop early in pregnancy, as major heart arteries and blood vessels are forming.
Congenital heart defects fall into six types.
Heart Valve Defects
Heart valves are very thin membranes attached to the wall of the heart. They open and close as they regulate blood flow. If they don’t operate correctly, blood won’t flow as it should. Pulmonary atresia — in which the pulmonary valve has failed to develop, leading to excessive blood flow to the lungs — is a common defect of this type. Ebstein’s anomaly — in which the tricuspid valve leaks due to malformation — is another.
Abnormal Blood Vessels
This describes arteries that are either positioned in the wrong way or are malformed. Coarctation of the aorta, for instance, is a condition in which the main blood vessel leading from the heart that supplies blood to the rest of the body is excessively narrow. High blood pressure is the result. If the aorta and the pulmonary artery are positioned on the wrong sides of the heart, the resulting condition is called transposition of the great arteries. It’s serious but rare and is usually detected within days of birth and corrected with surgery.
Holes in the Heart
Holes can occur in many places, such as between major blood vessels or in the walls between heart chambers. The problem here is that it can lead to a mix of oxygen-rich and oxygen-poor blood, leading to a general lack of oxygen being circulated throughout a child’s body. Symptoms can include shortness of breath and a blue tint to the skin and fingernails.
Heart Underdevelopment
This is when a large part of the heart fails to develop, hindering the organ’s ability to function properly.
Obstructed Blood Flow
This occurs due to valves or blood vessels being too narrow, leading to a bigger-than-normal workload for the heart as it struggles to push blood through a restricted space. This can lead to enlargement and thickening of the heart.
Combinations of Defects
Sometimes a complex of abnormalities can occur in the heart of the developing fetus. Tetralogy of Fallot is a prominent combination of this type, involving enlargement of the aorta, narrowing of the pulmonary valve, thickening of the muscular walls of the right ventricle and a hole between the right and left pumping chamber son the heart.
Serious congenital heart defects in infants are often diagnosed during pregnancy or soon after birth. Doctors may find a minor defect later in a child’s life, sometimes during a routine physical exam. If a pediatrician suspects a problem with a child’s heart, he or she may order diagnostic tests or refer the child to a pediatric cardiologist.
What Is a Congenital Heart Defect?
Congenital defects are abnormalities in the heart’s structure at or before birth. There are different types of defects, any of which may change the flow of blood through the heart.
Some defects are simple, have no symptoms and don’t need treatment. Others may require surgery to correct the problem. Heart defects are relatively common. Eight out of every 1,000 babies in the U.S. are born with heart problems according to the National Institutes of Health.
Physical Exams and Diagnostic Tests
A pediatrician uses a stethoscope to listen to a child’s heart and lungs. The physician will look for symptoms of heart problems. Signs of a heart defect include shortness of breath, delayed growth and cyanosis. Cyanosis is when the skin, lips and fingernails look blue.
The pediatrician may want a child to have further tests. Some tests used to look for defects are:
- Echocardiography: This test creates a moving picture of the heart. Sound waves bounce off the heart’s structures and are converted into images. Doctors examine the image, looking for problems. Fetal echocardiography can be done during pregnancy to create a picture of an unborn baby’s heart. A fetal echo is often done 18-22 weeks into a pregnancy.
- EKG (Electrocardiogram): An EKG records the heart’s electrical activity. Doctors can see the speed and rhythm of the heartbeat using this test. EKG’s are used to check for enlarged heart chambers which may indicate a problem.
- X-Ray: A chest X-ray creates an image of the internal organs. An X-ray will show if a heart is enlarged, or if the lungs show symptoms of heart problems.
- Pulseoximetry: This test estimates the amount of oxygen in the blood by placing a sensor on a finger or toe.
- Cardiaccatheterization: A tube, or catheter, is inserted into a vein and threaded into the heart. Dye is injected through the catheter. An X-ray shows doctors how the dye-stained blood is flowing through the vessels and heart.
Pediatric Cardiatric Center of Oregon provides in-office testing for heart defects in infants and children. Our doctors evaluate problems that range from the simple to the complex. Contact us today to make an appointment or learn more about our services.
