There are two types of strokes. The most common is the ischemic stroke, which accounts for almost 84% of all strokes. Ischemic strokes occur when a blood vessel to the brain becomes blocked by a clot or fatty deposit. The blockage prevents vital blood and oxygen from reaching part of the brain, causing damage to the brain. It is estimated that at least 31% of ischemic strokes are caused by an embolus. An embolus is a clot that forms in another part of the body and travels in the blood vessel until it becomes lodged in the brain.
The second type of stroke is a hemorrhagic stroke. Hemorrhagic strokes occur when a blood vessel wall in the brain ruptures, causing bleeding into the surrounding brain tissue. Hemorrhagic strokes account for 16% of all strokes.