Structural defects

Congenital Heart Disease (CHD) is caused by defects in the structure of the heart and its great vessels occurring at birth and accounts for 10% of infant mortality in India. One in every 125 babies born alive has CHD, which, incidentally, is also the most common birth defect. It is estimated that 2 lakh children are born every year with CHD in India. A large number of these infants are critically ill and need life-saving intervention in the first year of life. Many of these children, however, will have curable conditions with good long-term prognosis. Although the burden of CHD is huge, there are very few centres across the country that are capable of treating this condition.

Decoding CHD
The heart has valves, arteries and chambers that carry the blood in a circulatory pattern: body-heart-lungs-heart-body. When all chambers and valves work correctly, the blood is pumped through the heart, to the lungs for oxygen, back to the heart from the lung and out to the body for delivery of oxygen. When valves, chambers, arteries and veins are malformed, this pattern of circulation changes leading to different types of problems.

CHDs are structural problems of the heart present at birth. This happens during the development of the heart, due to many factors like viral illness, malnutrition, some medications and  causes such as point mutation like irradiation that the mother may be inadvertently exposed to soon after conception (which is often even before one is aware that she is pregnant).

Defects range from simple problems, such as ‘holes’ between chambers of the heart, to very severe malformations, such as complete absence of one or more chambers or valves.
Rarely can the cause be genetic. In such cases there is 2-15% chance of a heart defect happening again in the offspring. Most congenital heart problems are structural issues such as holes and leaky valves. For instance:

n Heart valve defects: A valve may be too narrow or completely closed, so the blood has a hard time passing through or can’t pass through at all. Or a valve might not close properly, so the blood leaks backwards.

n Problems with the heart walls: This includes problems between the chambers (atria and ventricles) of the heart. Holes or passageways between the left and right side of the heart might cause the impure and pure blood to mix together, when it shouldn’t.

n Issues with the heart muscle: Such complications can even lead to heart failure in some cases.

n Bad connections among blood vessels: In babies, this may let blood that should go to the lungs to get oxygen go to other parts of the body instead or vice versa. These defects can lead to heart failure, which means the heart doesn’t pump as efficiently as it should.

Symptoms
The symptoms of CHD in infants and children may include any of the following:
n A bluish tint to the skin, fingernails, and lips (doctors call this cyanosis)
n Fast breathing and poor feeding
n Poor weight gain
n Getting frequent lung infections
n Tiring easily during play
n Palpitations

In India, because congenital diseases are not covered by insurance, many patients do not come forward for treatment. Although some of the CHDs can be cured completely by timely treatment, others can only be palliated, which means procedures can be done to make the symptoms better.

It is important to get treatment at the right time to help manage the symptoms and reduce the risk of further problems. Some congenital defects of the heart need more than one procedure or surgery to correct them.

(The author is consultant cardiac surgeon, Fortis Hospital, Bengaluru)