The Different Types of Strokes

 An Ischemic Stroke happens when a blood clot blocks a blood vessel in the Brain. The build up of plaque* (see note below) on the walls of the arteries that supply blood to the brain, increases the chance of an ischemic stroke. The plaque could possibly stop the flow of blood to that part of the brain.

*Plaque is the build up of cholesterol, fatty deposits and other material. It gathers inside the wall of the blood vessel and narrows it (also called atherosclerosis). This may reduce blood flow to the brain. In certain situations a piece of plaque may break off and block an artery to the brain.

 

There are two types of Ischemic Strokes:

• A Thrombotic stroke is caused by a blood clot that forms in an artery directly leading to the brain.
• An Embolic stroke occurs when a clot develops some where else in the body and travels through the blood stream to the brain.

80% of Strokes are Ischemic. (Heart and Stroke Foundation)

 

A Hemorrhagic Stroke happens when a blood vessel ruptures in the brain, stopping normal blood flow and causing brain cells to die.

There are two main types of hemorrhagic stroke:

• Subarachnoid hemorrhage is uncontrolled bleeding on the surface of the brain, in the area between the brain and the skull.
• Intracerebral hemorrhage happens when a blood vessel ruptures deep within the brain.

Both types of hemorrhage (bleeding) can be caused by structural problems with the blood vessels in the brain. These include:

• Aneurysm: A weakened area in the wall of a blood vessel that fills with blood and bulges. High blood pressure or trauma can cause the bulge to rupture, causing uncontrolled bleeding into the brain.
• AVM (Arteriovenous Malformation): Brain blood vessels that were not formed properly during pregnancy that are usually present at birth. This causes the blood vessel walls to be weak and increases the risk of hemorrhagic stroke.

20 % of strokes are Hemorrhagic. (Heart and Stroke Foundation)