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        Health | Heart

Atherosclerosis occurs when fatty substances, cholesterol, cellular waste products, calcium, and other materials build up on the inside lining of the arteries. The buildup is more likely to be in parts of the artery that have been injured. The injury usually occurs where the artery bends or branches. Once plaque builds up, it may cause the cells in the artery lining to make chemicals that cause more plaque buildup.

Two problems can result from the plaque:

  • First, the blood vessel can become narrow, preventing blood flow to the area served by the artery. For example, if an artery to the heart becomes 80% to 90% blocked, a person can develop chest pain.
  • Second, the plaque can rupture and send a blood clot streaming through the artery. A blood clot that goes to other parts of the body is called an embolus. The embolus can be deposited in a smaller area of the artery or in another artery, completely cutting off the blood supply. This blockage can cause a heart attack, stroke, pulmonary embolus, or other serious medical problem.

What are the signs and symptoms of the disease?

The symptoms of atherosclerosis depend on which arteries are most affected by the buildup of plaque.

Atherosclerosis can affect the heart, the kidneys, and virtually any other organ.

  • Atherosclerosis of the arteries in the heart is called coronary artery disease. It can cause chest pain (angina), heart attack, or any of several other heart conditions.
  • Atherosclerosis of the blood vessels leading to the brain can cause a stroke.
  • Atherosclerosis of the blood vessels in the legs can result in leg pain during or after exercise. This is called intermittent claudication.
  • Atherosclerosis of the blood vessels that supply the kidneys can cause kidney failure.

What are the causes and risks of the disease?

There are several factors that increase a person's risk of developing atherosclerosis, such as: cigarette smoking and secondhand smoke, diabetes, high blood cholesterol, especially a high level of LDL ("the bad" or "lethal" cholesterol), high blood pressure, high levels of triglycerides in the blood, increased age, lack of exercise, male gender obesity.

What can be done to prevent the disease?

In some cases, atherosclerosis cannot be prevented. A person may be able to reduce his or her risk for developing atherosclerosis in the following ways:

  • Control diabetes
  • Eat a heart-healthy diet
  • Follow the American Heart Association, or AHA, recommendations for controlling high cholesterol
  • Get 30 minutes of physical activity every day or almost every day
  • Maintain a healthy body weight
  • Seek effective treatment for high blood pressure

How is the disease diagnosed?