Atherosclerosis

Atherosclerosis

Atherosclerosis is a disease characterized by the deposition of fatty Insert non-formatted text herewalls. The resident cells interpret this as an intrusion, "call for help", and inflammation results. Immune cells called monocytes circulating in the blood enter the artery wall, turn into macrophages and ingest the LDL particles, thereby turning into large "foam cells". The inflammation also causes a fibrous cap to be formed between the fatty deposits and the artery. These capped fatty deposits (called atheromas) narrow the blood vessel. This can lead to narrowing (stenosis) of the artery. The atheromas are fragile. When they rupture, a partial blockage can be quickly converted into a complete obstruction, resulting in a heart attack or stroke, depending on which artery is obstructed.

Risk factors

These risk factors for atherosclerosis are known:

having high blood concentration of LDL ("bad cholesterol") or of triglycerides and low concentration of HDL - High_density_lipoprotein ("good cholesterol"). HDL particles transport cholesterol from the tissues back to the liver.
aging and being male (women are affected more after menopause)
having close relatives who had heart disease or a stroke at a relatively young age
having high blood pressure
having diabetes
tobacco smoking
having trouble managing stress
being obese
being physically inactive
some chemicals indicating ongoing inflammation may also point to high risk

High-risk patients are given a low-fat diet, exercise and cholesterol-lowering drugs.

Treatment

If atherosclerosis leads to symptoms, the symptoms (such as angina) can be treated. Medicines are usually the first step in treating cardiovascular diseases. Other treatments include angioplasty procedures to open up clogged arteries and surgery, such as bypass surgery.

High blood pressure, diabetes, or high blood cholesterol can be treated as well. Lowering the blood cholesterol level can slow, stop, or even reverse the buildup of plaque. Cholesterol lowering can reduce the cholesterol content in unstable plaques to make them more stable and less prone to rupture.

Some of the text on this page has been taken from the public domain document at http://www.4woman.gov/faq/atheroscle.htm

References:

Peter Libby: Atherosclerosis: The New View, Scientific American Vol 286, No. 5, May 2002
Merck Manual: Atherosclerosis, http://www.merck.com/pubs/mmanual/section16/chapter201/201b.htm