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Stroke Care Center at the Gates Vascular Institute
What is a Stroke

A stroke or “brain attack” is the sudden interruption of blood flow to the brain. Because blood vessels deliver nutrients and oxygen to the brain, the lack of blood flow causes brain cells to die.

Types of Stroke

Ischemic

A) Ischemic

Ichemic Stroke

An ischemic stroke can be caused by a sudden blockage of one or more blood vessels leading to or within the brain. The blockage can be due to a “thrombus.”
A thrombus occurs when a blood clot forms within the blood vessel. Another form of blockage is caused by a blood clot that forms in a different part of the body such as the heart, neck or legs and travels to the brain. This type of blood clot is called an “embolus."

In general, blood clots, whether a “thrombus” or “embolus,” are formed when fatty substances form cholesterol deposits in the lining of blood vessel walls. This condition is called atherosclerosis. Ischemic stroke caused by an embolus is more common than that caused by a thrombus.

B) Hemorrhagic

A hemorrhagic stroke is caused by the rupture of weakened blood vessels in the brain. Blood then accumulates and compresses the surrounding brain tissue. Weakened blood vessels can be caused by longstanding high blood pressure or cerebral aneurysms.

An aneurysm is a weak or thin spot on a blood vessel wall. These weak spots may be present at birth or may be the result of atherosclerosis. Aneurysms develop over many years and usually do not cause problems until they rupture.


There are two types of hemorrhagic strokes:

  1. Intracerebral hemorrhage (ICH): Bleeding occurs from blood vessels within the brain itself. Poorly controlled blood pressure is the most common cause of this type of hemorrhage.
  2. Subarachnoid hemorrhage (SAH): Bleeding occurs when blood vessels just outside the brain rupture. Patients with SAH usually experience the worst headache of their life.

C) Transient Ischemic Attack (TIA) or Mini-Stroke

A TIA occurs when blood flow to certain parts of the brain are cut off for a short period of time. Symptoms usually last less than one hour but not more than 24 hours. TIAs should be treated seriously, as they are warning signs that a stroke may follow.