What is atherosclerosis?

Atherosclerosis thickening or hardening of the arteries. It is caused by a buildup of plaque in the inner lining of an artery. 

Normal artery and artery with plaque buildup

Plaque is made up of deposits of fatty substances, cholesterol, cellular waste products, calcium, and fibrin. As it builds up in the arteries, the artery walls become thickened and stiff.

Atherosclerosis is a slow, progressive disease that may start as early as childhood. However, it can progress rapidly.

What causes atherosclerosis?

It’s not clear exactly how atherosclerosis starts or what causes it. However, a gradual buildup of plaque or thickening due to inflammation occurs on the inside of the walls of the artery. This reduces blood flow and oxygen supply to the vital body organs and extremities.

What are the risk factors for atherosclerosis?

Risk factors for atherosclerosis, include:  

  • High cholesterol and triglyceride levels
  • High blood pressure
  • Smoking
  • Type 1 diabetes
  • Obesity
  • Physical inactivity
  • High saturated fat diet

What are the symptoms of atherosclerosis?

Signs and symptoms of atherosclerosis may develop gradually, and may be few, as the plaque gradually builds up in the artery. Symptoms may also vary depending on the affected artery. However, when a major artery is blocked, signs and symptoms may be severe, such as those occurring with heart attack, stroke, or blood clot.

The symptoms of atherosclerosis may look like other heart conditions. See your healthcare provider for a diagnosis.

How is atherosclerosis diagnosed?

First, your doctor will do a complete medical history and physical exam. You may also have one or more of these tests:

  • Cardiac catheterization. With this procedure, a long thin tube (catheter) is passed into the coronary arteries. X-rays are taken after a dye is injected into an artery to locate the narrowing, blockages, and other abnormalities of specific arteries.
  • Doppler sonography. A special probe is used to direct sound waves into a blood vessel to evaluate blood flow. An audio receiver amplifies the sound of the blood moving though the vessel. Faintness or absence of sound may mean there is a blockage. This is used to identify narrowing of the blood vessels of the abdomen, neck, or legs.
  • Blood pressure comparison. Comparing blood pressure measurements in the ankles and in the arms helps determine any constriction in blood flow. Significant differences may mean blood vessels are narrowed due to atherosclerosis.
  • MUGA/radionuclide angiography. This is a nuclear scan to see how the heart wall moves and how much blood is expelled with each heartbeat, while the person is at rest.
  • Thallium/myocardial perfusion scan. This is a nuclear scan given while the person is at rest or after exercise that may reveal areas of the heart muscle that are not getting enough blood.
  • Computerized tomography or CT. This is a type of X-ray test that can see if there is coronary calcification that may suggest a future heart problem. 
CT scan