What is atherosclerosis?

Although the exact process isn't completely understood, scientists have described different stages of atherosclerosis. These include:

Fatty streak.

The "fatty streak" appears as a yellow streak running inside the walls of an artery. The streak is made of cholesterol, white blood cells, and other cellular matter. The fatty streak can develop into a more advanced form of atherosclerosis, called fibrous plaque.

Plaque formation.

A plaque forms in the inner layer of the artery. Plaque is a buildup of cholesterol, white blood cells, calcium, and other substances in the walls of arteries. Over time, plaque may narrow the artery. This narrowing may limit the blood flow in the artery.

Stable and unstable plaque.

Plaques are defined based on the risk that they will tear or rupture.

• Stable plaque is less likely to rupture. These plaques have a thick fibrous cap. They are made of substances that are stable and not likely to rupture.
• Unstable plaque is more likely to rupture. These plaques have a thin fibrous cap. They are made of substances like fats that can expand. Inflammation within the plaque can make the fibrous cap unstable and more likely to tear apart.

Blocked artery.

A blockage in the artery can happen if the plaque tears or ruptures. This rupture exposes the cholesterol and tissue that was under the fibrous cap. Blood clots form in response to this rupture. The blood clot blocks the blood flow in the artery. This can cause a heart attack or stroke.

Many people don't have any symptoms. If you have symptoms, they may depend on where the affected arteries are in your body. For example, symptoms can include chest pain or pressure (angina), leg pain or weakness, or belly pain. Sometimes the first symptom is a heart attack or stroke.

Treating atherosclerosis may include having a heart-healthy lifestyle and taking medicines.

Atherosclerosis is a process. There are ways you can slow it down and help lower your risk for heart attack and stroke. A heart-healthy lifestyle can lower your risk. This includes eating heart-healthy foods, being active, staying at a healthy weight, and not smoking. All of these things have many benefits for your body, your heart, and your blood vessels.

If your risk for heart attack and stroke is high, you might also take medicines that lower your risk. Medicines may help reduce high cholesterol, control high blood pressure, and manage other things that increase a person's risk of heart attack, stroke, and other problems.

Your doctor will ask about your past health and will do a physical exam. You may have tests to see if your arteries are narrowed. Which tests you have depends on which arteries the doctor thinks are affected. Tests may include an electrocardiogram (EKG), an echocardiogram, heart stress tests, or a coronary angiogram.

There are many things you can do to help prevent problems. A heart-healthy lifestyle can lower your risk for heart attack and stroke. This includes eating healthy foods. Be active. If you smoke or vape, try to quit. Stay at a weight that's healthy for you. And try to get enough sleep.

Smoking plays a large role in atherosclerosis. The carbon monoxide and nicotine in tobacco smoke affect blood flow through your arteries. These substances:

• Make it easier for cholesterol-carrying lipoproteins to enter the walls of your arteries.
• Lead to the formation of fibrous plaque.
• Lead to the formation of blood clots. These clots can completely block your arteries.

Atherosclerosis is one of the causes of abdominal aortic aneurysm. Atherosclerosis seems to cause the walls of the aorta to weaken. Over time, the wall starts to grow larger in the area of the plaque. The end result is an aneurysm.

Atherosclerosis is sometimes called "hardening of the arteries." It occurs when fat (cholesterol) and calcium build up inside the lining of the artery wall. This forms a substance called plaque. Over time, the fat and calcium buildup may narrow the artery.

Atherosclerosis in the heart (coronary) arteries is called coronary artery disease. Atherosclerosis in the leg arteries is called peripheral arterial disease of the legs. If atherosclerosis affects the brain arteries (carotid or cerebral arteries), a stroke can occur.

If you have this buildup in one of your arteries, there's a good chance that you have it in other blood vessels throughout your body.

Atherosclerosis might start when the delicate inner lining of an artery is damaged. It might be damaged by things like high cholesterol, diabetes, high blood pressure, or smoking. Cholesterol in the blood moves into the wall of the artery and builds up.

This buildup of cholesterol seems to trigger inflammation and immune system responses from the body. These responses create plaque in the artery wall. Plaque contains fats, white blood cells, calcium, and other substances.