The coronary arteries sit on top of the heart and provide blood supply to the heart muscle itself. Blockages in the coronary arteries can lead to symptoms of chest pain or shortness of breath and may occasionally lead to congestive heart failure or heart attack. The cardiologist evaluates patients with suspected coronary artery disease and determines the optimal method for evaluating the heart. If blocked arteries are ultimately diagnosed, decisions are then made by the cardiologist and the patient on optimal therapy for the coronary artery disease. Treatment often involves medications to alleviate symptoms and to prevent the progression of plaque deposition. It is sometimes necessary to treat severe blockages with the placement of coronary stents or with bypass surgery. The cardiologist guides the patient through the diagnostic evaluation and counsels the patient on how to avoid heart attack and heart failure.