My dad has an enlarged heart. I am worried sick. Help?

Without reviewing the records from 6 years ago, it would be impossible to tell if this has occurred since that time. Enlargement of the heart occurs when the heart has to work harder to compensate for either damage caused by a heart attack or congestive heart failure which is a fluid build-up in the lungs plus other causes. This can often be treated with adjustment or adding new medications to keep his heart functioning at it's best that it can. You will have to wait and see what his cardiologist says. If he is going to his family physician, a visit to a cardiologist would also be indicated.