Congenital Heart Defect Awareness Week, observed from and sponsored by the American Heart Association, encourages awareness and education about congenital heart defects (CHDs).
No parent ever wants to hear the words congenital heart disease. These heart defects that children are born with affect the structure of the heart and the way blood flows through the heart’s chambers and valves. Congenital heart defects (CHDs) are the most common type of birth defect. There is about a one in 100 chance that a baby will be born with a CHD. That comes out to about 40 thousand babies each year.
The good news is that advances in diagnosis, care, and surgery for these babies have improved steadily over the last 30 years. At the end of 1990, less than 70 percent of babies survived the first year. Today, close to 70 percent of all babies born with CHDs are living into their adult years. In fact, for the first time, there are more adults alive with CHD than children.
What Causes CHDs?
In most cases, the cause of a CHD is never known. It may be a change (mutation) in a gene or combination of genes that occur during development in the womb. It may also be a combination of mutations that are passed down through families and triggered by a condition that effects a mother’s pregnancy. These conditions, called risk factors, include:
- Drinking alcohol
- Having German measles (rubella) during pregnancy
- Taking certain medications, such as thalidomide, ACE inhibitors, statins, and some acne medications
In most cases, there is nothing you can do to prevent a CHD. You should go over all your medications with your doctor before planning to get pregnant. Don’t drink or smoke. If you have diabetes, work with your doctor to get really good control of your blood sugar during pregnancy. Most people in America have been vaccinated for rubella with the MMR vaccine.
How Are CHDs Diagnosed?
Many CHDs can be diagnosed early in pregnancy with a routine fetal echocardiogram, an imaging study done with sound waves. Early diagnosis can allow for planning of treatment options before birth.
Some CHDs are not evident until after birth and doctors will look for early symptoms. Listening to the heart may reveal an abnormal heart sound called a heart murmur. One way to screen for a CHD is by placing a simple monitor on a newborn’s skin that measures oxygen in the blood. This painless test is called pulse oximetry. Signs and symptoms of a CHD in a baby include:
- Difficulty breathing
- A pounding heart
- A weak pulse
- Pale or blue color of the skin
- Poor feeding
- Unusual sleepiness
If a doctor suspects a CHD, other tests are done to diagnose the type of defect.
What Are Critical CHDs?
There are two types of CHDs. They are critical and non-critical defects. Non-critical defects are more common. These defects may not need surgery or they may be corrected without open heart surgery by placing a catheter into the heart (cardiac catheterization). They include:
- Ventricular Septal Defect. This is the most common defect. It is a hole between the lower chambers of the heart.
- Atrial Septal Defect. This defect is a hole between the upper chambers of the heart. This hole may cause increased blood flow into the lungs.
Critical heart defects almost always cause a low pulse oximetry reading in a newborn. These defects make up about 25 percent of CHDs. Critical CHDs will need surgery or a procedure in the first year of life, some of these will need open heart surgery. They include:
- Coarctation of the Aorta, narrowing of the main blood vessel leaving the heart
- Dextro-Transposition of the Great Arteries, the two main blood vessels leaving the heart – one going to the body and the other to the lungs – get switched
- Hypoplastic Left Heart Syndrome, the left side of a baby’s heart does not form correctly
- Pulmonary Atresia, the valve that controls flow of blood from the heart to the lungs does not form
- Tetralogy of Fallot, a hole between the lower chambers, narrowing of the pulmonary artery, an aortic valve defect, and thickening of the right lower chamber
- Total Anomalous Pulmonary Venous Return, blood from the lung returns to the right side of the heart instead of the left
- Tricuspid Atresia, failure of the valve that controls blood flow from the right upper to the right lower chamber of the heart
- Truncus Arteriosus, the aorta and the pulmonary artery leave the heart as a single, fused artery
Who Treats Children With CHDs?
The improved survival of children with CHD is due to advances in technology and the skills of a team of health care specialists who have trained for many years to care for these children. They include pediatric cardiac surgeons, pediatric cardiologists, neonatologists, pediatric intensive care specialists, and many other health care providers for nursing care, nutrition, and physical therapy.
The survival of babies, children, and adolescents with CHDs is now so common, that a whole new group of specialists has evolved to take care of adults with CHDs. Adult congenital heart disease specialists will help most babies born with a CHD live longer and more productive lives into their adult years.