Cardiology is a branch of internal medicine. A cardiologist is not the same as a cardiac surgeon. A cardiac surgeon opens the chest and performs heart surgery.

A cardiologist specializes in diagnosing and treating diseases of the cardiovascular system. The cardiologist will carry out tests, and they may perform some procedures, such as heart catheterizations, angioplasty, or inserting a pacemaker.

Heart disease relates specifically to the heart, while cardiovascular disease affects the heart, the blood vessels, or both.

To become a cardiologist in the United States, it is necessary to complete 4 years of medical school, 3 years of training in internal medicine, and at least 3 years specializing in cardiology.