Stroke

Causes

• Ischemic Stroke (Most Common, ~87% of strokes):
  • Occurs when the blood vessels supplying the brain become narrowed or blocked, leading to severely reduced blood flow (ischemia).
  • Thrombotic Stroke: A blood clot (thrombus) forms in an artery that supplies blood to the brain. Often occurs in arteries damaged by atherosclerosis (fatty deposits).
  • Embolic Stroke: A blood clot or other debris forms away from the brain, typically in the heart, and travels through the bloodstream to lodge in narrower brain arteries. A common cause is atrial fibrillation (an irregular heartbeat).
  • Risk Factors for Ischemic Stroke: High blood pressure, high cholesterol, diabetes, obesity, smoking, heart disease (e.g., atrial fibrillation, heart failure), carotid artery disease, sickle cell anemia, sedentary lifestyle, excessive alcohol consumption.
• Hemorrhagic Stroke (Less Common, but often more severe):
  • Occurs when a blood vessel in the brain leaks or ruptures. Blood spills into or around the brain, creating pressure and damaging brain cells.
  • Intracerebral Hemorrhage: The most common type of hemorrhagic stroke, where a blood vessel bursts within the brain tissue. High blood pressure is a primary cause.
  • Subarachnoid Hemorrhage: Bleeding occurs in the space between the brain and the membranes covering the brain (subarachnoid space). Often caused by a ruptured aneurysm (a balloon-like bulge in a blood vessel).
  • Risk Factors for Hemorrhagic Stroke: High blood pressure, ruptured brain aneurysm, arteriovenous malformation (AVM - abnormal tangle of blood vessels), anticoagulant medications, trauma, smoking, drug abuse (e.g., cocaine).
• Transient Ischemic Attack (TIA - "Mini-stroke"):
  • Caused by a temporary disruption of blood flow to part of the brain, spinal cord, or retina, causing stroke-like symptoms that last only a few minutes to an hour and cause no permanent damage.
  • A TIA is a warning sign of a future stroke and requires immediate medical attention.

Symptoms

• F - Face Drooping: One side of the face droops or is numb. Ask the person to smile. Is the smile uneven?
• A - Arm Weakness: One arm is weak or numb. Ask the person to raise both arms. Does one arm drift downward?
• S - Speech Difficulty: Speech is slurred, or the person is unable to speak or is hard to understand. Ask the person to repeat a simple sentence. Is it correct?
• T - Time to call emergency services: If anyone shows any of these symptoms, even if the symptoms go away, call emergency services immediately.
• Other Sudden Symptoms May Include:
  • Sudden numbness or weakness of the leg, arm, or face.
  • Sudden confusion or trouble understanding speech.
  • Sudden trouble seeing in one or both eyes.
  • Sudden trouble walking, dizziness, loss of balance, or coordination.
  • Sudden severe headache with no known cause.

Diagnosis

• Physical Exam and Neurological Assessment: Doctors will check symptoms, reflexes, vision, speech, and strength.
• Blood Tests: To check blood clotting time, blood sugar levels, and other factors that could contribute to stroke or mimic its symptoms.
• Imaging Tests:
  • CT Scan (Computed Tomography): Often the first imaging test. It can quickly show bleeding in the brain (distinguishing hemorrhagic from ischemic stroke) and can identify large ischemic strokes later.
  • MRI (Magnetic Resonance Imaging): Provides more detailed images of brain tissue and can detect ischemic strokes earlier than CT.
  • CT Angiography (CTA) or MR Angiography (MRA): Use dye and imaging to look at the blood vessels in the brain and neck to identify blockages or aneurysms.
  • Carotid Ultrasound: Uses sound waves to check for narrowing or blockages in the carotid arteries (major arteries in the neck supplying the brain).
  • Echocardiogram: To check for blood clots in the heart that could travel to the brain.

Treatment

• For Ischemic Stroke (to restore blood flow):
  • Emergency IV Medication (tPA - Tissue Plasminogen Activator): Administered within 3-4.5 hours of symptom onset for eligible patients. This "clot-busting" drug can dissolve the clot and restore blood flow.
  • Endovascular Procedures (Mechanical Thrombectomy): For large vessel occlusions, a catheter is threaded through an artery, usually in the groin, to the brain to physically remove the clot. This can be done up to 6-24 hours after symptom onset in select cases.
  • Medications: Antiplatelet drugs (e.g., aspirin, clopidogrel) or anticoagulants (e.g., warfarin, direct oral anticoagulants) to prevent future clots.
• For Hemorrhagic Stroke (to control bleeding and reduce pressure):
  • Emergency Measures: Control bleeding, reduce pressure in the brain, manage blood pressure.
  • Medications: To lower blood pressure, reduce brain swelling, or reverse the effects of blood thinners.
  • Surgery:
    • Surgical Clipping: A tiny clamp is placed at the base of a brain aneurysm to stop blood flow to it.
    • Endovascular Coiling: Coils are threaded into an aneurysm to block blood flow.
    • Craniotomy: To relieve pressure on the brain or remove a large blood clot.
• Post-Stroke Rehabilitation:
  • Crucial for recovery and often begins in the hospital.
  • Physical Therapy: To regain strength, balance, and coordination.
  • Occupational Therapy: To improve ability to perform daily activities (dressing, eating).
  • Speech and Language Therapy: For problems with speaking, understanding, reading, or swallowing.
  • Cognitive Therapy: For issues with memory, problem-solving, and judgment.
  • Psychological Counseling: To address depression, anxiety, or emotional changes.
• Prevention of Recurrence:
  • Long-term management of risk factors: controlling blood pressure, diabetes, cholesterol; quitting smoking; maintaining a healthy weight; regular exercise; healthy diet.
  • Medications to prevent future strokes (e.g., antiplatelets, anticoagulants).
  • Surgical procedures (e.g., carotid endarterectomy or angioplasty and stenting) to clear blocked neck arteries.

After a Stroke or TIA: Preventing the Next One

Surviving a stroke puts you in the group most likely to have another, and the months that follow are when secondary prevention matters most. The treatments are well established; the gap is usually in whether they are started, continued, and adjusted.

A TIA is a stroke warning with a short fuse

Symptoms that resolve within minutes are not reassuring. The risk of a completed stroke after a transient ischemic attack is highest in the first 48 hours and stays elevated for weeks, and same-day evaluation with imaging, a cardiac rhythm check, and immediate antiplatelet treatment cuts that risk substantially. Waiting for a routine appointment is the wrong response.

Blood thinning matched to the cause

Which drug prevents the next stroke depends on what caused the first. For strokes from artery narrowing, an antiplatelet such as aspirin or clopidogrel is used, and a short course of both together after a minor stroke reduces early recurrence. When atrial fibrillation is found, an anticoagulant such as apixaban is needed instead, because antiplatelet drugs do little against clots that form in the heart. Finding intermittent atrial fibrillation sometimes requires weeks of rhythm monitoring.

Blood pressure and cholesterol targets are lower than before

After a stroke the blood pressure goal is below 130/80, and LDL cholesterol is driven below 70 mg/dL with a high-intensity statin such as atorvastatin, which reduces recurrence even when the starting cholesterol looked normal. High blood pressure remains the single most important modifiable cause. Significant narrowing of a carotid artery on the affected side may warrant a procedure, covered in our carotid artery disease article.

Recovery continues longer than people are told

Most functional recovery happens in the first three to six months, but gains continue well beyond that with sustained therapy, and the plateau people are warned about is often a plateau in services rather than in potential. Depression affects about a third of stroke survivors, slows rehabilitation, and responds to treatment; the major depressive disorder page covers what that looks like. Fatigue, emotional lability, and changes in thinking are common and worth naming at follow-up rather than enduring.

Learn the signs again, for the people around you

Family members are usually the ones who call 911. The BE FAST version adds balance loss and eye or vision changes to face drooping, arm weakness, and speech difficulty. Our neurology team manages post-stroke care alongside rehabilitation. The CDC and NINDS publish guidance on prevention and recovery.

If you have had a stroke or TIA and are unsure whether your blood pressure, cholesterol, or blood thinner is at target, schedule a review.