Atherosclerosis is a disease in which fatty substances such as cholesterol, cellular waste, calcium and other substances are deposited along the lining of artery walls in a person's body. These sticky, yellowish deposits, known as plaque, build up over time, hindering blood flow. If this hinderance occurs in the coronary blood vessels of the heart the person could experience a heart attack. If it occurs in the brain the person can experience a stroke.

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What is the cause of atherosclerosis?

Is atherosclerosis rare amongst healthy individuals? Explain.

How can a fat deposit, accumulating under the surface of the arterial wall cause a heart attack or stroke?

Blood flows through blood vessels with very little resistance, as shown on the right. Diseases, such as atherosclerosis, cause the blood to flow slowly or not at all through blood vessels. Atherosclerosis is often referred to as hardening of the arteries and is a normal degenerative condition associated with ageing. However, lifestyle and diet can significantly accelerate atherosclerosis.

Atherosclerosis typically affects medium and large arteries in the body and is believed to start with damage to the endothelium, the innermost layer of the artery.

The fat deposit, plaque, may just disrupt the flow of blood but not completely stop it. At worst the plaque may burst through the endothelial layer of the artery and cause a blood clot which stops the flow of blood. A surgical procedure may be required to insert a stent.

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