The term heart disease is a very broad term. Problems can arise within the heart muscle, arteries supplying blood to the heart muscle, or the valves within the heart that pump blood in the correct direction. Understanding the differences between each disease of the heart can help with the confusing applications of the term heart disease.

Coronary artery disease or CAD is the most common type of heart disease and the leading cause of death in both genders in the U.S. Coronary artery disease affects the arteries supplying blood to the heart muscle. These coronary arteries harden and narrow due to the buildup of a waxy cholesterol, fatty substance referred to as plaque.