If you think you or a loved one might be having a stroke, call 911. For more information about Stroke Warning Signs, visit the Stroke Warning Signs page or view or download the F.A.S.T. Stroke Warning Signs PDF.

For information on stroke benchmarks and outcomes, visit the Stroke Outcomes page.

What is a Stroke?

A stroke, sometimes called a brain attack, occurs when a clot blocks the flow of blood to the brain (ischemic stroke) or when a blood vessel in the brain breaks (hemorrhagic stroke). The decrease in blood flow to the brain can result in temporary or permanent brain injury. This is why every minute counts in getting treated for stroke, which is the fifth-leading cause of death in the United States.

Effects of Stroke

Damage from stroke can affect your entire body resulting in mild to severe disabilities including the inability to move your arm, leg or both, and problems with memory, thinking, speaking, swallowing, and emotions. If a stroke occurs and blood flow can't reach the region that controls a particular body function, that part of the body won't function as it should. Your symptoms tell us where the stroke happened in the brain and how much of the brain is involved.

Types of Stroke

There are two types of stroke: ischemic and hemorrhagic.

Ischemic Stroke

Ischemic stroke is the most common type of stroke, accounting for approximately 87% of strokes. It occurs when a blood clot blocks the flow of blood to your brain. If the body cannot clear the blockage, then the area is permanently damaged.

There are 2 types of ischemic strokes:

  • Thrombotic strokes: These are caused by a blood clot (also called thrombus) that forms in the blood vessels inside the brain.
  • Embolic strokes: These are caused by a wandering blood clot (also called embolus) or plaque debris that forms somewhere else in your body (usually heart or neck) and then travels to one of the blood vessels in the brain through the bloodstream.

Hemorrhagic Stroke

A hemorrhagic stroke is less common than an ischemic stroke. It occurs when a weak blood vessel breaks and bleeds into the brain.

There are 2 types of hemorrhagic strokes:

  • An intracerebral hemorrhage (ICH) is caused by a weak blood vessel breaking in the brain.
  • A subarachnoid hemorrhage (SAH) is caused by a weak blood vessel breaking on the surface of the brain.

Transient Ischemic Attack (TIA)

A transient ischemic attack (TIA) — also referred to as a "mini-stroke" or "warning stroke" — is a temporary interruption of the blood flow to an area of the brain. A TIA indicates that someone is at risk for having a stroke. We are very aggressive about lowering the risk of a stroke in patients who have received this warning.

Stroke Treatment

Treatment for a stroke depends on whether it is an ischemic or hemorrhagic stroke, how long it’s been since your stroke happened and other factors. Your doctor will select the best treatment for you. Below is a list of common procedures your doctor may recommend.

Treatments for Ischemic Stroke

tPA Clot-Busting Medication: Clot-busting medication (tPA) can be administered if the patient arrives quickly and tPA can be started within 4.5 hours of the first stroke symptoms. This brain-saving treatment can reduce the long-term effects of stroke and provides the best chance for a full recovery.

Timing is critical for treating patients with ischemic stroke. Michigan Medicine has consistently exceeded the American Heart Association goals and national and Michigan benchmarks for expedited treatment.

Visit the Stroke Outcomes page for more information on benchmarks and outcomes.

Endovascular Thrombectomy: Endovascular thrombectomy is a minimally invasive procedure that uses a stent retriever to trap and remove the blood clot. Doctors thread a catheter through an artery in the groin or arm up to the blocked artery in the brain. The stent opens and "grabs" the clot, allowing doctors to remove the stent with the trapped clot. The procedure typically takes 60 to 90 minutes.

Illustration showing a surgical clip inserted at the bottom of a brain aneurysm

Treatments for Hemorrhagic Stroke

  • Clipping (aneurysm) - A surgery for treatment of brain aneurysms, involving placing a surgical clip at the bottom of the aneurysm to remove the blood flow and reduce the risk of rupture. An aneurysm is a ballooning of the artery from a weak artery wall.
  • Coiling (aneurysm) - A treatment of an aneurysm by filling it with detachable coils to reduce the risk of rupture
  • Craniotomy - A procedure that removes a section of the skull to access the brain for surgery, such as the clipping of an aneurysm. This piece of the skull is returned to its original position at the end of surgery. Sometimes craniotomies are referred to as stealth-guided craniotomies, as image guidance is used to perform the procedures.
  • Craniectomy -  Craniotomy is a procedure that removes a section of the skull, but with this method the bone plate is left off for an extended period of time. This method is less commonly used, mostly in cases where the underlying brain tissue has experienced major swelling.
Illustration showing detachable coils filling an aneurysm

Visit the Stroke Outcomes page for more information about clipping and coiling benchmarks and outcomes.





Treatments to Prevent Another Stroke

  • Carotid Endarterectomy - A surgery to remove fatty deposits from the carotid artery to prevent a stroke.
  • Carotid Stent Placement - A meshwork tube that widens a narrow artery usually done to prevent stroke or recurrent stroke.

Visit the Stroke Outcomes page for more information about carotid procedure outcomes.

Stroke Intervention for High-Risk Patients

We screen patients who are high risk for stroke in the stroke clinic located in the Frankel Cardiovascular Center and discuss preventive measures to decrease their risk for stroke.

The University of Michigan Stroke Program

The U-M Stroke Program is accredited as a Comprehensive Stroke Center by the Joint Commission. We have repeatedly been designated as an American Heart Association Gold Plus stroke hospital, the highest stroke quality designation. We also surpass state and national benchmarks for tPA treatment and treatment time.

Stroke patients at U-M are cared for in a dedicated Stroke Unit and Neuro-Intensive Care Unit (NICU). During the patient’s stay, vascular neurologists, neurosurgeons, neuroscience nurses with advanced training in stroke care, and a medical team containing experts in stroke treatment and complications all work together so patients can have optimal recovery for their individual situation.

For more information about our center, accreditations and awards, visit the About the U-M Comprehensive Stroke Center page.

Next Steps

For Patients: If you think you or a loved one might be having a stroke, call 911. If you have had a stroke in the past or think you might be at risk for one call us at 1-888-287-1082 to make an appointment for a consultation. Visit our Stroke Patient Resources page for more information about stroke, including videos and care guides.

For Physicians: If you are a physician and want to refer a patient, call M-LINE at 800-962-3555.

For Stroke Coordinators: If you are a stroke coordinator and want to find out more about our process or have questions, please contact our Comprehensive Stroke Center at