Cardiac diseases are also known as heart diseases. Cardiac diseases are a very broad term for a number of conditions that affect the heart and as of 2007, it is the leading cause of death in England, Wales, and the United States.

The leading cause of cardiac disease is a narrowing of the lumen of arteries that supply blood to the heart, commonly called coronary artery disease (CAD).

There are various other heart conditions that come under the umbrella of cardiac diseases.

A number of conditions that affect the heart itself or any of the arteries or veins leading to and from the heart are called cardiovascular diseases. Long studies have suggested that women are more prone to conditions that affect the blood vessels themselves while men are more prone to conditions that affect the heart muscles. The most common conditions that cause cardiovascular diseases are:

A disease of the heart itself where the arteries supplying the heart muscles are clogged by atheromatous plaques. An atheroma is a collection or a swelling on the vessel wall composed of fats, cell debris, calcium, connective fibrous tissues, etc.

a Angina - chest pain due to the insufficient blood supply to the heart 'Ischemic heart disease', is another term used to denote a condition where the blood supply to the heart is reduced.