Coronary artery disease (CAD) occurs when the coronary arteries - the blood vessels that supply blood to the heart - are narrowed or blocked. Arteries become narrowed or blocked when fat (cholesterol) and calcium and other products in the blood build up inside the lining of the arteries forming a plaque. This process is called atherosclerosis or hardening of the arteries.
Atherosclerosis can, and often does, affect arteries throughout the body, including the ones that supply blood to the heart, the brain (cerebrovascular disease), and your arms and legs (peripheral vascular disease).
When plaque builds up inside the coronary arteries, the blood flow to the heart is reduced. Ischemia is the term doctors use to describe the condition in which blood flow to the heart is reduced.· When an area of the heart doesn't receive enough blood, chest pain or discomfort (angina) may occur.
Over time, reduced blood flow may weaken the heart muscle so that it is not able to pump effectively. This may result in other serious conditions, such as cardiomyopathy or heart failure.
If a plaque should break open or rupture, a blood clot could form which could block blood flow to the heart muscle. This is when a heart attack (myocardial infarction or MI) occurs. During a heart attack, portions of the heart muscle cells die because they are deprived of blood, oxygen, and nutrients.
The following conditions are strong risk factors for coronary artery disease:
- Smoking
- Obesity
- Uncontrolled high blood pressure
- High cholesterol
- Diabetes
- A family history of heart disease
- Stress
- Sedentary lifestyle
If any of these risk factors are detected and treated at an early stage, it may be possible to prevent or, in some cases, even reverse the effects of coronary artery disease. With lifestyle changes and the use of new cholesterol-lowering medication, some risk factors can be reduced before CAD develops. Medical evidence has shown that lowering cholesterol is a good step for almost everyone - especially people with heart disease and people who have two or more risk factors for coronary artery disease. Lowering cholesterol can help reduce the risk of heart attack, stroke, and death in many individuals with average to high cholesterol levels.
If coronary artery disease exists or is causing problems, doctors can prescribe medication or surgical procedures to treat the blocked arteries and to relieve symptoms while possibly preventing a heart attack, heart failure, or early death.
