Atherosclerosis: A process of progressive thickening and hardening of the walls of medium-sized and large arteries as a result of fat deposits on their inner lining.
Atherosclerosis comes from the Greek words athero (meaning gruel or paste) and sclerosis (meaning hardness). The combination of the two meanings provides a rather gruesome picture of a hard paste (plaque) being deposited in our blood vessels. Not a pretty sight from any angle.
It is believed by many scientists that this dreaded condition begins when damage occurs to the innermost layer of the artery. Such damage can be caused by…
- High levels of cholesterol
- High triglycerides
- High blood pressure
- Smoking
- Diabetes
- Obesity
Smoking (and other tobacco use) greatly increases atherosclerosis development and growth, especially in the aorta and large arteries such as those in the legs and those leading to the heart (coronary arteries).
Because of the damage, over time fats, cholesterol, platelets, cellular debris and calcium are deposited in the artery wall. These substances may stimulate the cells of the artery wall to produce still other substances. This results in more cells accumulating in the innermost layer of the artery wall where the atherosclerotic lesions form. These cells accumulate, and many of them divide. At the same time, fat builds up within and around these cells. They also form connective tissue.
The innermost layer of the artery becomes markedly thickened by these accumulating cells and surrounding material. If the wall is thickened sufficiently, the diameter of the artery will be reduced and less blood will flow, thus decreasing the oxygen supply.
Often a blood clot forms and blocks the artery, stopping the flow of blood. If the oxygen supply to the heart muscle is reduced, a heart attack can occur. If the oxygen supply to the brain is cut off, a stroke can occur. And if the oxygen supply to the extremities occurs, gangrene can result.
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