Cardiomyopathy: Cardiomyopathy is a disease of the heart that can be caused by a variety of other diseases, conditions, medications, and heredity. Cardiomyopathy causes can be categorized in several ways. One classification system is primary and secondary cardiomyopathy, another is extrinsic or intrinsic. The most common symptoms of cardiomyopathy are shortness of breath, chest pain, and fatigue. Treatment is generally directed toward the underlying cause of the disease. Prognosis can be very good, or in some cases very poor with heart transplant as the only option.