What Is an Ischemic Stroke?
An ischemic stroke occurs when a blood clot or blockage cuts off blood flow to a part of the brain. This deprives brain tissue of oxygen and nutrients, leading to brain cell death within minutes. It is the most common type of stroke, accounting for about 85% of all strokes.
Types of Ischemic Stroke
There are two main types:
- Thrombotic stroke – caused by a blood clot (thrombus) forming in an artery supplying the brain.
- Embolic stroke – caused by a clot or debris that travels from another part of the body (commonly the heart) to the brain.
What Causes It?
Ischemic strokes typically result from:
- Atherosclerosis – buildup of fatty deposits in blood vessels
- Blood clots from the heart (often due to atrial fibrillation)
- Narrowing of arteries in the neck or brain
- Heart attacks or valve disease
- Blood clotting disorders
Who’s at Risk?
Several factors increase the risk, including:
- High blood pressure
- Diabetes
- High cholesterol
- Smoking
- Obesity
- Sedentary lifestyle
- Heart conditions, especially atrial fibrillation
- Family history of stroke
- Age over 55
- Previous stroke or transient ischemic attack (TIA)
What Are the Symptoms?
Symptoms of an ischemic stroke usually come on suddenly. Key warning signs include:
- Sudden numbness or weakness, especially on one side of the body
- Confusion, trouble speaking, or understanding speech
- Sudden trouble seeing in one or both eyes
- Difficulty walking, dizziness, or loss of balance
- Severe headache with no known cause
Use the acronym FAST to remember the signs:
- Face drooping
- Arm weakness
- Speech difficulty
- Time to call emergency services
How Is It Diagnosed?
Quick diagnosis is vital. Tests may include:
- CT scan or MRI – to visualize the brain and rule out bleeding
- Blood tests – to check for clotting issues, sugar levels, and infection
- Carotid ultrasound – to check for narrowing in neck arteries
- Echocardiogram – to check for heart-related sources of clots
- Angiography – to view blood flow in brain vessels
What Are the Treatment Options?
Emergency Treatment (within hours of onset)
- tPA (Tissue Plasminogen Activator) – a clot-busting drug given within 4.5 hours of symptoms onset
- Mechanical thrombectomy – removal of the clot using a catheter (in selected patients)
Ongoing Management
- Antiplatelet drugs (e.g., aspirin, clopidogrel)
- Anticoagulants (e.g., warfarin, DOACs) – especially in atrial fibrillation
- Blood pressure and cholesterol control
- Diabetes management
- Lifestyle changes (healthy diet, exercise, quitting smoking)
Rehabilitation
- Physical therapy – to regain movement
- Speech therapy – if speech or swallowing is affected
- Occupational therapy – to relearn daily activities
Can It Be Prevented?
Yes, many strokes are preventable through:
- Managing blood pressure, cholesterol, and diabetes
- Taking prescribed medications
- Quitting smoking
- Staying physically active
- Eating a balanced diet
- Maintaining a healthy weight
- Monitoring and treating heart conditions like atrial fibrillation
When to Seek Medical Help
Stroke is a medical emergency. Call emergency services immediately if you or someone else shows symptoms. Time lost is brain lost — the sooner treatment begins, the better the chances of recovery.