Types of Strokes

Strokes are life-threatening emergencies.

Strokes happen when blood flow to the brain is disrupted, preventing brain cells from getting the oxygen and nutrients they need. Quick action is critical to limit damage. 

Knowing the difference between types of strokes helps with preventing them and with getting the right treatment. For example, clot-busting drugs can be lifesaving in ischemic strokes but could make a hemorrhagic stroke worse.

What are the different types of strokes?

The three main types of strokes are: 

• Ischemic stroke 
• Hemorrhagic stroke 
• Transient ischemic attack (TIA) 

Ischemic stroke

An ischemic stroke is the most common type of stroke. About 87% of all strokes are this type. 

An ischemic stroke occurs when an artery that supplies blood to the brain becomes blocked. That usually happens due to a blood clot that forms in the blood vessels in or leading to the brain. A buildup of fatty deposits in the artery walls (atherosclerosis) may make the arteries more narrow and increase the risk of clots forming in them.

With an ischemic stroke, brain cells in the area begin to die. You start to lose the functions controlled by that part of the brain. How severe the effects are depends on where in the brain the stroke is located and how much of the brain tissue is blocked.

Types of ischemic stroke

There are two main types:

• Thrombotic stroke: These strokes happen when a clot forms directly in one of the brain’s arteries. They are usually linked to atherosclerosis. You’re at higher risk for a thrombotic stroke if you have high cholesterol, diabetes or a family history of heart disease. Smoking, eating a lot of unhealthy foods and being physically inactive increase your risk. 
• Embolic stroke: These strokes happen when a clot forms somewhere else in the body, often the heart, and travels to the brain. The clot becomes lodged in a smaller artery and blocks blood flow. You’re at higher risk for an embolic stroke if you have a history of heart attack or heart failure or you have certain heart conditions, including atrial fibrillation, which causes irregular heartbeats that can lead to clots.

Hemorrhagic stroke

A hemorrhagic stroke happens when a blood vessel in the brain ruptures and causes bleeding in or near the brain. Hemorrhagic strokes are less common than ischemic strokes, but they are usually more severe and can be life-threatening. A hemorrhagic stroke is a medical emergency.

They are often caused by: 

• High blood pressure 
• Weak blood vessel walls 
• Aneurysms 
• Arteriovenous malformations (AVMs) 
• Liver disease 

Types of hemorrhagic stroke

There are two main types:

• Intracerebral hemorrhage: These strokes happen when you have bleeding directly into the brain tissue. They are often caused by high blood pressure, which stresses and weakens small arteries in the brain. Other causes include trauma, blood-thinning medications (anticoagulants) and brain tumors.
• Subarachnoid hemorrhage: These strokes happen when you have bleeding in the space between the brain and the surrounding membrane (the subarachnoid space). They are often caused by ruptured aneurysms or head injuries. With one, you may have a sudden, severe headache that feels like the worst headache of your life.

What is a transient ischemic attack (TIA)?

A transient ischemic attack (TIA), often called a mini stroke, happens when the blood flow to the brain is blocked temporarily. TIAs have similar symptoms to other strokes but the symptoms go away in minutes or hours. 

TIAs happen when a clot blocks an artery, but your body dissolves it and your blood flow returns to normal.

Risk factors for TIA include: 

• High blood pressure 
• High cholesterol 
• Atrial fibrillation  

A TIA is a major warning sign that you might have a stroke in the future. About one-third of people who have a TIA have a more severe stroke within a year if they don’t manage their risk factors. If you have a TIA, you need an immediate medical evaluation to identify and reduce your risk of another stroke.

How to recognize stroke symptoms  

Time is critical with any type of stroke. Recognizing symptoms and acting quickly can make a difference.

The letters FAST can help you remember the main stroke symptoms:

• Face drooping: One side of the face may droop or feel numb.
• Arm weakness or numbness: Try to raise both arms and notice if one drifts down.
• Speech issues: Speech may be slurred or hard to understand.
• Time to call 911: A stroke is a medical emergency. Call for help immediately. Even with a TIA, where symptoms often disappear quickly, you need care right away.

You may also notice other symptoms based on the type of stroke:

• Ischemic stroke or TIA: Sudden confusion, trouble walking
• Hemorrhagic stroke: Sudden severe headache, nausea, vomiting or loss of consciousness 

Describing stroke symptoms you notice in yourself or someone else can help health care providers figure out which type of stroke is happening so they can provide the right treatment.

Stroke care at Banner Health

At Banner Health, we are committed to expert stroke care and prevention. Our team can help you: 

• Understand your stroke risk 
• Manage related conditions like high blood pressure or atrial fibrillation 
• Take steps to prevent future strokes 

If you or a loved one experiences stroke symptoms, getting fast care matters. We’re here to guide you every step of the way.  

Learn more about stroke symptoms, diagnosis and treatment.