Arteriosclerosis is the medical term used to describe changes within the lining of an artery leading to “hardening” of the arteries. It is the chief precursor to heart attacks, peripheral artery disease (PAD) and some strokes.
The arteries are the body’s plumbing, allowing oxygen-carrying blood to travel to all parts of the body. Since all cells need oxygen to create energy for life-sustaining processes, the arteries play an integral part in normal body function. Without oxygen and nutrients, cells will die.
Lining the inside of each artery are specialized layers of cells that work to keep the artery open and the blood flowing. The innermost layer is very thin and smooth to allow the blood cells easy passage. Beneath the inner layer are multiple layers of cells that provide both structural support and flexibility to the vessel. Embedded smooth muscles both dilate and constrict the blood vessel.
As we age, time takes its toll on the arteries. They will lose some of their flexibility, getting stiffer. Years of traffic through the vessels can cause microscopic damage to the inner lining. Elevated blood pressure similarly affects the arteries. These changes as well as oxidative stress produce areas within the arteries that are prone to blockage.
Oxidative stress refers to the effects that certain reactive byproducts from normal chemical reactions have on the body. These byproducts, also called free radicals or oxidants, are normally eliminated by the body’s natural antioxidants. Over time, however, they may accumulate and lead to damaged tissues.
Another process that affects the walls of the arteries is the collection of cholesterol on the arterial lining. When too much cholesterol is flowing through the blood stream, it can attach to and is taken up by scavenger cells within the vessel wall. This leads to an inflammatory reaction within the artery wall resulting in thickening and scarring (sclerosis); the thicker the wall, the less space there is for blood to travel through the vessel.
This is what happens in the arteries of the heart in coronary artery disease and in the legs with peripheral arterial disease (PAD). Symptoms of these conditions reflect the degree of blockage that has occurred in the heart or leg arteries.
For example, let’s say an individual has moderate hardening of a coronary artery. This vessel supplies blood flow to the heart muscle. During exertion or exercise, the muscles are working harder and require more blood flow/oxygen. However, enough blood can’t get through that tight artery to meet the demand. As the activity continues, the individual starts to experience pain in the chest. This is called “angina.” When referring to pain in the legs with exercise, it is called “claudication.”
If the heart muscle or other vital tissues are repeatedly deprived of blood flow and oxygen, the muscle cells can die and eventually scar. This is why it is so important to prevent, diagnose and treat arteriosclerosis early.
Prevention starts with regular aerobic exercise, a heart healthy, low-fat, low-cholesterol diet and avoiding smoking. High blood pressure and cholesterol should be identified early through regular checkups and aggressively treated to lower the risk of arteriosclerosis.
The content in this column is for informational purposes only. Consult your physician for appropriate individual treatment. Dr. Reynolds practices Family Medicine in Chesterfield.