Enlarged heart has no scientific name because it is not a specific condition – rather, a problem caused by another problem. In someone born with an enlarged heart, a congenital birth defect may have caused the change in size. The abnormal size may affect the ability of the heart to function normally. An enlarged heart also can be caused by other conditions, such as heart attack, high blood pressure, abnormal heartbeat and cardiomyopathy (thickening and stiffening of heart muscle). You are at great risk for developing an enlarged heart if you have a family history of heart disease, heart attack or high blood pressure.