Types of Stroke

Strokes can be classified into two main categories:

  • 87 percent are ischemic strokes - strokes caused by blockage of an artery
  • 13 percent are hemorrhagic strokes - strokes caused by bleeding

Hemorrhagic Stroke

Hemorrhagic strokes occur when a blood vessel that supplies the brain ruptures and bleeds. When an artery bleeds into the brain, brain cells and tissues do not receive oxygen and nutrients. In addition, pressure builds up in surrounding tissues and irritation and swelling occur. About 13 percent of strokes are caused by hemorrhage (10 percent are intracerebral hemorrhage and 3 percent are subarachnoid hemorrhage strokes).

Ischemic Stroke

An ischemic stroke occurs when a blood vessel that supplies the brain becomes blocked or "clogged" and impairs blood flow to part of the brain. The brain cells and tissues begin to die within minutes from lack of oxygen and nutrients. The area of tissue death is called an infarct. 

About 87 percent of strokes fall into this category. Ischemic strokes are further divided into two groups, including the following:
• thrombotic strokes - caused by a blood clot that develops in the blood vessels inside the brain;
• embolic strokes - caused by a blood clot or plaque debris that develops elsewhere in the body and then travels to one of the blood vessels in the brain via the bloodstream.

Transient Ischemic Attack

Transient  Ischemic Attack (TIA) is often called a “mini stroke,” and is caused by a temporary clot. The only difference between a stroke and TIA is that the blockage is temporary in a TIA. The symptoms occur rapidly and last a relatively short time. Most TIAs last less than five minutes; the average is about a minute. Unlike a stroke, when a TIA is over, there’s usually no permanent injury to the brain. 

This mini-stroke is often characterized as a “warning stroke,” and any symptom should be taken very seriously. Stroke Warning Signs.

Copyright © 1997-2018 BJC HealthCare. All Rights Reserved.