Stroke is a brain attack. It happens when blood flow to the brain is either cut off (ischemic stroke) or when there is too much blood on the brain (hemorrhagic stroke).

More than 80 percent of strokes are ischemic strokes. When blood flow to the brain is reduced by a blood clot or blocked artery, your brain cells do not get the oxygen and nutrients needed, and can begin to die within minutes. A blood clot can form in the arteries of the brain or in the carotid arteries in your neck that carry blood to the brain. A stroke can also be caused by an “embolus” – a blood clot that forms in a blood vessel not located in your brain. Emboli are most often formed in your heart and are carried through your bloodstream into the much smaller blood vessels in your brain where they block normal blood flow.  

Hemorrhagic stroke is a less common type of stroke, but have a much greater risk of death and permanent disability. This type of stroke occurs when a blood vessel in your brain leaks or ruptures. Bleeding can be caused by many conditions – uncontrolled high blood pressure, untreated high cholesterol and weak portions of your blood vessels (aneurysms). 

In either type of stroke, quick action is extremely important!  The faster you recognize symptoms in you or a loved one, the faster you can make it to a hospital to receive treatment.  It is possible for doctors to treat a stroke, but stroke treatment  depends on how quickly you can get to the hospital. In most cases, the treatment window is between three and eight hours. 

Learn more about how to recognize the symptoms of a stroke.