Types of Stroke: What is a Stroke? Stroke Symptoms and Signs

There are two primary types of stroke called Ischemic and Hemorrhagic stroke.

There are also two secondary types of stroke called a TIA and Silent Stroke. TIA stands for Transient Ischemic Attack, and this type of stroke is also known as “mini-strokes. “

Ischemic Stroke

Ischemic stroke is responsible for the vast majority of stroke cases worldwide. Statistics say anywhere from 82% to 88% of strokes are caused by Ischemic stroke.

Ischemic strokes occur because of a blockage (or blood clot) within a blood vessel or artery that supplies the brain with oxygen and glucose. Without oxygen and glucose being supplied to the brain, cells within the brain begin to die rapidly. The underlying cause for most Ischemic stroke cases is atherosclerosis – or the buildup of fat deposits within blood vessel structures.

As a result of these fat deposit buildups, there can be two root causes for Ischemic stroke:

  1. Thrombosis
  2. Embolism


Thrombosis is a blood clot that occurs where fatty deposits clog a blood vessel.


Embolism is a blood clot that forms somewhere else in the bloodstream. The clot or part of the clot can break loose and travel through the bloodstream until it reaches a blood vessel that is too narrow or obstructed to allow the clot to pass, causing a blockage.

Most embolisms are formed near the heart or other large arteries within the body and are often the result of an irregular heartbeat (known as Atrial Fibrillation). It is important to know or find out if you have an irregular heartbeat to prevent embolisms from occurring.

Transient Ischemic Attack

A Transient Ischemic Attack is a temporary episode of weakness or paralysis due to a very short-term blood flow blockage to the brain. Transient Ischemic Attack is not a true stroke because the symptoms are temporary and typically conclude within 24 hours, and does not cause permanent brain damage or disability. TIA is a risk factor for having more traumatic strokes in the future or silent strokes.

Silent Stroke

A Silent stroke is a type of stroke that has no symptoms. A person may lose blood flow or hemorrhage in the brain without even knowing that a minor stroke occurred. These types of strokes can be detected via neuroimaging tools such as a CT scan, resulting in verifiable lesions on or within the brain. A person who has suffered Silent Stroke is at risk of having Transient Ischemic Attacks or a major Ischemic or Hemorrhagic stroke.

Hemorrhagic Stroke

A “hemorrhage” is another word for bleeding. In this type of stroke, a hemorrhage or bleeding occurs within the brain due to a weakened or ruptured blood vessel. Hemorrhagic is much less common than Ischemic Stroke and accounts for approximately 10%-18% of stroke cases worldwide.

Many types of conditions affect blood vessels. Here we will list the three most common reasons why a hemorrhage in a blood vessel may occur.

  • Uncontrolled high blood pressure (also known as Hypertension)
  • Aneurysms or weak spots in a blood vessel wall
  • Arteriovenous Malformation (known as AVM) rupture. This is more uncommon and is an abnormal “tangle” of blood vessels that is genetic, and a person is born with.

There are two sub-types of Hemorrhagic Stroke:

  1. Intracerebral Hemorrhage
  2. Subarachnoid Hemorrhage

Intracerebral Hemorrhage

Intracerebral hemorrhage is a type of hemorrhagic stroke where a blood vessel ruptures in the brain and begins to bleed into the nearby brain and kill nearby tissues. Adjacent tissue and cells are also damaged. Hypertension or high blood pressure is the primary root cause of an Intracerebral hemorrhage.

Small arteries within your brain become weakened over time due to prolonged pressure and can burst or break. It is important to monitor and control your blood pressure to prevent this type of hemorrhage.

Subarachnoid Hemorrhage

Subarachnoid is a scientific name for the space between your brain and your skull. A Subarachnoid Hemorrhage is another type of hemorrhagic stroke most commonly caused by the bursting or rupture of an aneurysm at or near the brain surface.

The bleeding subsequently creates pressure on the brain’s surface and can cut off oxygen and blood flow to nearby brain tissues.