Stroke or Cerebral Vascular Accident (CVA)

By Joel Fuhrman, M.D.

A stroke is the sudden death of brain cells due to a problem with the blood supply. When blood flow to the brain is impaired, oxygen and important nutrients cannot be delivered. The result is injury and then death to brain cells resulting in abnormal brain function. Blood flow to the brain can be disrupted by either a blockage or rupture of an artery to the brain.

A stroke is also referred to as a Cerebral Vascular Accident (CVA). It is called a Temporary Ischemic Attack (TIA) when the symptoms are temporary (less than 24 hours), and a stroke when the loss of brain function is permanent.

Types of Strokes
There are two major types, embolic or ischemic stroke and hemorrhagic strokes.

Stroke by common usage usually refers to the more common embolic or ischemic stroke. These strokes occur from a blood clot that occurs inside the vessel and prevents blood flow to brain. Besides the development of atherosclerotic plaque and high blood pressure, other factors increasing the risk of stroke include smoking, diabetes, leukemia, aplastic anemia, brain tumors, gout and birth control pills. High homocysteine levels in the blood can also increase the risk of stroke.

Causes of Strokes
A clot that cuts off blood flow to a part of the brain is the most common cause. Plaque material or pieces of blood clots that travel to the brain are other common sources.

Overall, the chief cause of strokes are related to hardening of the arteries, which allows fatty deposits to accumulate inside the arteries causing a cascade of injury to the vessel walls eventually leading to clots that form inside the blood vessels. The slow development of asterosclerosis, which decreases blood flow to the brain, results in shrinkage of the brain and the development of dementia. A stroke can also result from bleeding or from a bursted blood vessel in the brain as the result of high blood pressure.

Most CVAs are the result of atherosclerosis, hypertension or a combination of both.