What Is Coronary Artery Disease (CAD)?

Transcript

Dr. Mansfield
Coronary artery disease is a condition in which the arteries that supply blood to the heart become hardened and narrowed. Dr. Patel, can you tell us more?

Dr. Patel
Sure, Dr. Mansfield. Plaque is a waxy substance made up of fat, cholesterol, calcium, and other substances in the blood, and covered by a thin outer shell called the fibrous cap. When plaque builds up inside the arteries, which are vessels that carry oxygen-rich blood to tissues and organs throughout the body, it's a condition called atherosclerosis.

The coronary arteries supply oxygen-rich blood to the heart. Coronary artery disease occurs when atherosclerosis affects these arteries. Over time, the plaque that builds up can harden and narrow the arteries, which reduces the blood supply to the heart muscle.

Plaque buildup also makes it more likely that blood clots will form in the arteries. If the plaque breaks open or part of the fibrous cap breaks off, blood cell fragments called platelets stick to the site of the rupture. When the platelets clump together, they form a blood clot. A large blood clot can mostly or completely block blood flow.

When blood flow to the heart muscle is reduced or blocked, it can cause chest pain, called angina, or a heart attack. In addition, coronary artery disease can weaken the heart muscle over time, which can lead to heart failure and arrhythmias, or problems with the rate or rhythm of the heartbeat.