Cerebral Infarction (Ischemic Stroke)

Overview

A cerebral infarction, also called an ischemic stroke, occurs when blood flow to part of the brain is suddenly blocked. Without a steady supply of oxygen and nutrients, brain cells in the affected area begin to die within minutes. The result is loss of the functions that part of the brain controlled, such as movement, speech, or vision.

Cerebral infarction is one of the most common and serious causes of disability and death worldwide. It is a medical emergency: the faster blood flow is restored, the more brain tissue can be saved. The phrase "time is brain" reflects how quickly damage accumulates, which is why recognizing the warning signs and calling for emergency help immediately is critical.

Symptoms

Symptoms usually begin suddenly and depend on which part of the brain is affected. A useful way to remember the main signs is the word FAST:

• F — Face: drooping or numbness on one side of the face
• A — Arm: weakness or numbness in one arm or leg
• S — Speech: slurred speech or trouble speaking or understanding
• T — Time: call emergency services right away

Other symptoms can include sudden confusion, vision loss in one or both eyes, severe dizziness or loss of balance, difficulty walking, and a sudden severe headache. Any sudden neurological symptom is an emergency. Call emergency services immediately even if the symptoms seem to improve.

Causes

A cerebral infarction happens when an artery supplying the brain becomes blocked. The main mechanisms are:

• Thrombosis: a blood clot forms directly in a narrowed brain artery, often where fatty plaque has built up.
• Embolism: a clot or debris forms elsewhere, often in the heart, and travels to the brain where it lodges and blocks a vessel.
• Small-vessel disease: tiny deep arteries become narrowed and blocked, often related to long-standing high blood pressure or diabetes.

Conditions such as an irregular heartbeat (atrial fibrillation), hardening of the arteries, and clotting disorders all raise the chance of these blockages.

Risk Factors

Many risk factors for cerebral infarction can be managed. They include:

• High blood pressure, the leading risk factor
• Atrial fibrillation and other heart conditions
• Diabetes
• High cholesterol and atherosclerosis
• Smoking
• Obesity and physical inactivity
• Previous stroke or transient ischemic attack (TIA)
• Older age and family history

Diagnosis

Rapid diagnosis is essential so that treatment can begin within the narrow time window. Doctors use:

• CT scan of the head: performed quickly to rule out bleeding and help guide treatment.
• MRI: shows the area of brain injury in greater detail.
• CT or MR angiography: maps the blood vessels to find the blockage.
• Blood tests and ECG: check blood sugar, clotting, and heart rhythm.
• Carotid ultrasound and echocardiogram: look for the source of clots after the emergency phase.

Treatment

Treatment focuses on restoring blood flow quickly and preventing further strokes. Options include:

• Clot-dissolving medication: a drug given through a vein can break up the clot if given within a few hours of symptom onset.
• Mechanical thrombectomy: a procedure to physically remove a large clot using a catheter, effective in selected patients.
• Blood-thinning and antiplatelet drugs: to prevent new clots after the acute phase.
• Managing risk factors: controlling blood pressure, cholesterol, diabetes, and irregular heart rhythm.
• Rehabilitation: physical, occupational, and speech therapy to recover lost function.

Recovery varies widely and depends on the size and location of the infarction and how quickly treatment was given.

Prevention

Many cerebral infarctions can be prevented by controlling risk factors. Helpful steps include:

• Keeping blood pressure in a healthy range
• Managing diabetes and cholesterol
• Not smoking
• Treating atrial fibrillation, often with blood thinners
• Staying physically active and maintaining a healthy weight
• Eating a balanced diet low in salt and saturated fat
• Taking prescribed medications after a stroke or TIA

When to See a Doctor

Call emergency services immediately if you or someone else has any sudden sign of a stroke:

• Face drooping on one side
• Weakness or numbness in an arm or leg
• Slurred or confused speech
• Sudden vision loss, severe dizziness, or trouble walking
• Sudden, severe headache with no known cause

Note the time symptoms began, because this affects which treatments can be used. Do not wait to see if symptoms pass, even if they briefly improve.

Related Topics

Frequently Asked Questions

References

1. National Institute of Neurological Disorders and Stroke (NINDS). Stroke Information.
2. Centers for Disease Control and Prevention (CDC). About Stroke.
3. Mayo Clinic. Stroke — Symptoms and causes.
4. American Stroke Association. Ischemic Stroke (Clots).