Cardiomegaly is a condition where the heart enlarges in response to damage of the heart muscle. Enlarged heart is usually a symptom of another condition such as coronary artery disease, structural heart disease, a thyroid disorder, high blood pressure, abnormal heart rhythms or problems with the heart muscle itself. While some people may experience no symptoms for enlarged heart, others may experience shortness of breath, swelling or abnormal heart rhythm. A physician can diagnose cardiomegaly using an imaging test, such an x-ray to look at the heart. Problems with the heart can also be identified with a stress test, where the heart function is check during stress (e.g. while exercising). Another way to diagnose cardiomyopathy is with blood tests or a biopsy, where a needle is used to take out heart tissue to look at under a microscope. Treatments for cardiomegaly focus on treating the cause of cardiomegaly. Medications, specialized procedures and surgeries may be prescribed by a physician to treat cardiomegaly.