Slideshows Images Quizzes
font size

Coronary Angioplasty (cont.)

Medical Author:
Medical Editor:

How does coronary artery disease develop?

Arteries that supply blood and oxygen to the heart muscles are called coronary arteries. Coronary artery disease (CAD) occurs when cholesterol plaque (a hard, thick substance comprised of varying amounts of cholesterol, calcium, muscle cells, and connective tissue, which accumulates locally in the artery walls) builds up in the walls of these arteries, a process called arteriosclerosis. Over time, arteriosclerosis causes significant narrowing of one or more coronary arteries. When coronary arteries narrow more than 50% to 70%, the blood supply beyond the plaque becomes inadequate to meet the increased oxygen demand of the heart muscle during exercise. Lack of oxygen (ischemia) in the heart muscle causes chest pain (angina) in most people. However, some 25% of those with significant coronary artery narrowing experience no chest pain at all despite documented ischemia, or may only develop episodic shortness of breath instead of chest pain. These people are said to have "silent angina" and have the same risk of heart attack as those with angina. When arteries are narrowed in excess of 90% to 99%, people often have angina at rest (unstable angina). When a blood clot (thrombus) forms on the plaque, the artery may become completely blocked, causing death of a part of the heart muscles (heart attack, or myocardial infarction).

The arteriosclerotic process can be accelerated by smoking, high blood pressure, elevated cholesterol levels, and diabetes. Individuals are also at higher risk for arteriosclerosis if they are older (greater than 45 years for men and 55 years for women) or if they have a positive family history of coronary heart disease.


Heart Health

Get the latest treatment options.

Use Pill Finder Find it Now See Interactions

Pill Identifier on RxList

  • quick, easy,
    pill identification

Find a Local Pharmacy

  • including 24 hour, pharmacies

Interaction Checker

  • Check potential drug interactions
Search the Medical Dictionary for Health Definitions & Medical Abbreviations
Atrial Fibrillation Quiz

Health Solutions From Our Sponsors