About Stroke
A stroke occurs either when bleeding occurs in the brain--a hemorrhagic stroke--or a blood clot, blockage or plaque buildup in a blood vessel blocks blood flow to the brain--an ischemic stroke. The severity of a stroke and its effects can vary depending on damage to the brain, but strokes can be fatal or cause severe disability. There are many known risk factors for stroke, but high blood pressure is the greatest risk indicator. According to the World Heart Federation, high blood pressure is the primary cause of as many as 50 percent of ischemic strokes.
Damage to the Arteries
High blood pressure causes significant damage to the arteries when it goes untreated for a long period, says the American Heart Association, or AHA. When the force, or pressure, of the blood flowing through the arteries is greater than normal, those arteries weaken over time. Weakened arteries are more susceptible to burst, or rupture, leading to a hemorrhagic stroke. Chronic high blood pressure is one of the primary reasons why hemorrhagic stroke occurs, says the AHA.
Buildup in the Arteries
The damage inside the blood vessels in the brain causes plaque buildup, says Johns Hopkins. Plaque is a thick substance composed of fats and cholesterol that build up inside blood vessels and reduce blood flow. These plaques can rupture, creating a blood clot, which can then become lodged in a blood vessel and block blood supply to the brain, resulting in a stroke.
