A number of conditions can lead to heart enlargement, also called cardiac hypertrophy, in infants. Around 1 percent of infants have congenital cardiac defects, the most common congenital defect found in newborns, the American Heart Association reports.

An enlarged heart, also referred to as cardiomegaly, is a symptom of another medical condition, such as heart valve problems and coronary artery disease. Symptoms of an enlarged heart include difficulty breathing, cough, dizziness and chest pain.

An enlarged heart, or cardiomegaly, is often a symptom of one of several underlying conditions. Some conditions that can cause an enlarged heart include high blood pressure, heart failure, coronary artery disease, a heart valve problem, and pregnancy.

Cardiomegaly is the medical term used to describe an enlarged heart. While usually detected by an X-ray, this condition is considered a symptom of an underlying disease, such as coronary artery disease. In some cases, however, it may be a temporary condition due to stress placed on your body due to pregnancy.

An enlarged heart, or cardiomegaly, is a symptom of another medical condition; it is not a disease in itself. The condition is often treatable if therapy is directed at treating the underlying cause of the heart enlargement.