Ischemic Stroke

Understanding the most common type of stroke

What is an Ischemic Stroke?

An ischemic stroke is a "brain attack" caused by a blockage in a blood vessel that supplies blood to the brain. It is the most common type of stroke, accounting for about 87% of all strokes.

The word "ischemic" means a lack of blood flow. Without a constant supply of oxygen- and nutrient-rich blood, brain cells begin to die within minutes. This can lead to permanent brain damage, long-term disability, or even death.

How It Happens: The Blockage

The core problem is a blocked artery that prevents blood flow to part of the brain. This blockage occurs in two primary ways:

Thrombotic Stroke (Cerebral Thrombosis)

A blood clot (thrombus) forms directly in an artery supplying the brain. This often occurs in arteries that have been damaged or narrowed over time by atherosclerosis, which is a buildup of fatty deposits called plaque.

Embolic Stroke (Cerebral Embolism)

A clot or other debris (called an embolus) forms somewhere else in the body—most commonly in the heart or the large arteries of the neck. This clot then travels through the bloodstream until it reaches a brain artery too narrow for it to pass, where it lodges and creates a blockage. A common cause is atrial fibrillation (AFib), an irregular heart rhythm.

Risk Factors

Several conditions increase the risk of ischemic stroke. Key factors include atherosclerosis, high blood pressure (the #1 controllable risk factor), high cholesterol, atrial fibrillation, diabetes, smoking, obesity, and physical inactivity.

Recognizing the Symptoms: Act F.A.S.T.

Brain damage from a stroke is time-sensitive. Recognizing the signs and getting immediate medical help is critical.

F - Face Drooping: Does one side of the face droop or is it numb? Ask the person to smile. Is the smile uneven?

A - Arm Weakness: Is one arm weak or numb? Ask the person to raise both arms. Does one arm drift downward?

S - Speech Difficulty: Is speech slurred, strange, or hard to understand? Ask the person to repeat a simple sentence.

T - Time to Call Emergency Services: If you see any of these signs, even if they go away, call for an ambulance immediately. Note the time when symptoms first appeared.

Other sudden symptoms can include numbness or weakness in the leg, face, or especially on one side of the body; confusion; trouble speaking or understanding speech; vision problems; trouble walking; dizziness; loss of balance or coordination; or a severe headache with no known cause.

Diagnosis and Treatment

In the emergency room, doctors perform a physical exam and use brain imaging scans like CT scans or MRIs to confirm a stroke and determine if it's ischemic.

Treatment focuses on quickly restoring blood flow to the brain. Time is critical - every minute of delay kills more brain cells.

Clot-Busting Drugs (Thrombolytics)

The most common is tPA (tissue plasminogen activator). This IV medication can dissolve the clot but must be administered within a few hours (typically 4.5 hours) of symptom onset.

Mechanical Thrombectomy

A procedure where a doctor threads a catheter through an artery to physically remove the clot. This is highly effective for large clots and can be performed up to 24 hours after symptoms for some patients.

After emergency treatment, long-term care focuses on preventing another stroke using medications like antiplatelets (e.g., aspirin) or anticoagulants (e.g., warfarin), along with managing underlying conditions like high blood pressure and diabetes.

Remember: Time = Brain. If you suspect a stroke, call emergency services immediately. Quick action can save lives and reduce long-term disability.

Medical Information Resource | This information is for educational purposes and not a substitute for professional medical advice.