Congenital Heart Disease
Congenital heart disease (CHD) is any birth defect which affects the heart or the large blood vessels. Congenital means that the defect is present at birth.
What is going on in the body?
There are many different birth defects that can affect the heart. For example, the valves of the heart may be missing or not work properly. In other cases, there may be holes in the walls of the heart or abnormal connections between blood vessels and the heart.
The defects can range from mild abnormalities that cause no problems to life-threatening ones that require surgery hours after birth.
Some common congenital heart defects include:
- atrial septal defect (ASD), an abnormal opening between the two upper chambers of the heart
- ventricular septal defect (VSD), an abnormal opening between the two lower chambers of the heart
- tetralogy of Fallot, a set of four typical heart abnormalities
- coarctation of the aorta, which is a narrowing of the aorta
- pulmonary atresia, an abnormality of the opening between the heart and the arteries to the lungs
- patent ductus arteriosus, an abnormal opening between the aorta and the artery to the lung
- transposition of the great vessels, a switch in the normal positions of the aorta and the artery to the lung
What are the causes and risks of the disease?
Many times the cause of CHD is unknown. Known causes of CHD include:
- alcohol and drug abuse by a mother during pregnancy
- certain medicines used by a mother during pregnancy such as those used to treat seizures
- diseases affecting the mother, such as diabetes
- genetic, inherited, or chromosomal defects such as those that occur with Down syndrome
- viral infections of the fetus during pregnancy, especially rubella
What can be done to prevent the disease?
Often nothing can be done to prevent CHD. Women of childbearing age should make sure they have received all standard vaccines. This can help prevent cases due to certain viral infections during pregnancy, such as rubella. Avoiding alcohol and substance abuse during pregnancy will further reduce the risk for CHD.
How is the disease diagnosed?
CHD is usually evident on physical exam, though further tests are generally needed to define what kind of CHD the infant has. Some of these include:
- an EKG, which measures the electrical activity of the heart
- a chest X-ray, which allows the doctor to see the size and position of the heart
- an echocardiogram, which is a test that uses sound waves to see the beating heart. This test can check how well the heart is beating and also makes many heart defects visible.
- a cardiac catheterization, which allows measurement of blood flow and pressure within the heart and great vessels
- a special three-dimensional computerized X-ray (ultra fast CT) which is less invasive and exposes the infant to less radiation than catheterization
Long Term Effects
What are the long-term effects of the disease?
Small defects may eventually repair themselves and cause no long-term effects. The long-term effects usually depend on how severe the CHD is. Some untreated heart defects can be fatal. Larger defects usually cause more symptoms. The outcome of these is largely dependent on whether surgery is feasible and technically successful.
Until the defect is corrected, the heart is under a lot of strain. It may become larger in size and may not beat in a normal rhythm. People who have this disease can develop high blood pressure, and their lungs can become congested. Those with heart defects are often at an increased risk for heart infections, which may be life threatening.
What are the risks to others?
CHD itself is not contagious and poses no risk to others. However, infections that cause CHD, such as the rubella virus, may be contagious. Genetic causes of CHD may be passed on to one's children. Genetic counseling may be helpful for some parents.
What are the treatments for the disease?
Treatment often involves open heart surgery to correct the heart defect. Sometimes more than one defect occurs at the same time and more than one operation is needed. With certain defects, medication alone may be sufficient treatment, and other cases may need no treatment other than observation.
What are the side effects of the treatments?
Surgery to correct a heart defect can be simple or very complicated. Side effects of treatment depend on the severity of the defect. Some people recover completely, while others may still have a problem with high blood pressure and a very strained heart. The heart may not beat in a normal rhythm. Surgery itself can be very risky and sometimes fatal. Bleeding and infection may also occur.
What happens after treatment for the disease?
The person needs time to recover fully after surgery. Antibiotics to help fight infection and other medicines to help the heart may be given after surgery. Close monitoring of the heart and lungs is needed. Sometimes, a person will need more surgery later in life.
If the problem is corrected, the person can live a normal life and participate in sports and other activities like anyone else. Those whose defects cannot be totally corrected may face some limitations; however, as with any other disability, each person should be encouraged to challenge him or herself within reasonable limits. The healthcare provider can help determine the best approach for each individual.
How is the disease monitored?
A person with CHD should make regular visits to the healthcare provider. He or she will check the heartbeat, blood pressure, and the status of the blood circulation and lungs. Annual influenza vaccination is very important for people with CHD because complications of flu can be serious or even fatal. Any new or worsening symptoms should be reported to the doctor.
Harrisons Textbook of Medicine 1991
Merck Manual 2000
Current Therapy and diagnosis 1996