Atherosclerosis

Overview

You’ve probably heard of plaque on your teeth, but your body also has another type of plaque. This is plaque that builds up in your arteries, the blood vessels that carry oxygen and nutrient-rich blood from your heart to your body’s tissues.

Plaque in the arteries is a fatty, waxy substance that forms deposits in your artery walls that can narrow the arteries and reduce blood flow. This is called atherosclerosis or “hardening of the arteries.” Plaque can also rupture and create a blood clot at the rupture site, as your body’s natural processes try to repair the “injury.” The blood clot can cut off blood flow through the artery and starve your body’s tissues of oxygen and nutrients. Thus, a ruptured plaque can be serious, as it’s the most common cause of a heart attack or stroke.

What is plaque made of?

Arterial plaque is made up of materials that enter the artery wall from the bloodstream. These include fat, cholesterol, calcium, waste products from cells, and a clotting agent called fibrin. This is why your doctor tests your cholesterol levels. High levels of low-density lipoprotein (LDL) — or “bad” — cholesterol can indicate a higher risk of plaque buildup.

What causes plaque in arteries?

Unfortunately, plaque buildup in your arteries is a natural part of living. Even children and adolescents have early evidence of the process.

However, diet and other lifestyle factors play an important role. High blood pressure, high LDL cholesterol, and smoking can all worsen atherosclerosis. High blood pressure and the toxins in tobacco products damage the smooth inner lining of the arteries, called the endothelium. These and other causes of inflammation of the artery lining contribute to cholesterol and other materials embedding in the artery wall to form plaque.

Additionally, some people are predisposed to having atherosclerosis. A genetic condition called familial hypercholesterolemia causes some people to have abnormally very high LDL cholesterol levels in the bloodstream.

Is all plaque dangerous?

Plaque builds up in arteries throughout the body, but not all plaque is equally dangerous. You might hear the term vulnerable plaque. This refers to a soft plaque that has a thin, fibrous cap. This plaque is more likely to rupture, causing a blood clot to form at the rupture site and cutting off or restricting blood flow, thereby potentially causing a heart attack or stroke.