Cardiology s a branch of medicine that deals with the disorders of the heart as well as some parts of the circulatory system. The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology. Physicians who specialize in this field of medicine are called cardiologists, a specialty of internal medicine. Pediatric cardiologists are pediatricians who specialize in cardiology. Physicians who specialize in cardiac surgery are called cardiothoracic surgeons or cardiac surgeons, a specialty of general surgery.Cardiology is a medical, not surgical, discipline. Cardiologists provide the continuing care of patients with cardiovascular disease, performing basic studies of heart function and supervising all aspects of therapy, including the administration of drugs to modify heart functions.