Cerebral infarction

Ischemic Stroke
Synonyms	N/A
Pronounce	N/A
Field	Neurology, Emergency medicine
Symptoms	Sudden numbness, confusion, vision loss, dizziness, severe headache
Complications	Brain damage, seizures, paralysis, dementia, death
Onset	Sudden
Duration	Variable, may be permanent
Types	Thrombotic stroke, Embolic stroke, Transient ischemic attack
Causes	Atherosclerosis, blood clot, cardioembolism
Risks	Hypertension, smoking, diabetes mellitus, hyperlipidemia, atrial fibrillation, obesity
Diagnosis	CT scan, MRI, carotid ultrasound, blood tests
Differential diagnosis	Hemorrhagic stroke, migraine, seizure, brain tumor
Prevention	Healthy lifestyle, antiplatelet drugs, blood pressure control, cholesterol management, HPV vaccine
Treatment	Thrombolysis, thrombectomy, anticoagulation, rehabilitation
Medication	Tissue plasminogen activator, aspirin, clopidogrel, warfarin
Prognosis	Better with early treatment; worsens with time and extent of damage
Frequency	Most common type of stroke
Deaths	Major cause of disability and mortality worldwide

An ischemic stroke is a type of stroke that occurs when the blood supply to a part of the brain is interrupted or reduced due to a blood clot or plaque obstructing a blood vessel. This deprives brain tissue of oxygen and nutrients, leading to cell death within minutes. Ischemic strokes account for approximately 85% of all strokes.

Causes

Atherosclerosis and Plaque Buildup

Atherosclerosis occurs when fatty deposits, known as plaque, build up inside the arteries. This process can narrow the arteries, including those in the neck (such as the carotid arteries), reducing blood flow and increasing the risk of stroke. If a plaque ruptures, it can trigger the formation of a blood clot.

Blood Clots and Emboli

Blood clots may form directly in cerebral vessels (thrombotic stroke) or elsewhere in the body—such as the heart—and travel to the brain (embolic stroke). Conditions like atrial fibrillation, myocardial infarction, and valvular heart disease can increase the risk of emboli.

Inflammation

Chronic inflammation—due to infections or autoimmune disorders such as lupus or rheumatoid arthritis—can damage vascular walls and promote clot formation, contributing to ischemic stroke risk.

Transient Ischemic Attack (TIA)

A transient ischemic attack or "mini-stroke" is caused by a temporary blockage of blood flow to the brain. Symptoms usually resolve within minutes to hours and do not cause permanent damage, but TIAs are warning signs for future full-blown strokes.

Risk Factors

Common risk factors for ischemic stroke include:

• Hypertension
• Diabetes mellitus
• Hyperlipidemia
• Smoking
• Atrial fibrillation and other cardiac arrhythmias
• Carotid artery disease
• Use of oral contraceptives
• Obesity and physical inactivity
• Excessive alcohol consumption and drug abuse
• Chronic kidney disease
• Sleep apnea
• Age (risk increases over 55)
• Sex (men at younger age; women higher lifetime risk)
• Race and ethnicity (higher in African Americans, Native Americans, Hispanics)
• Genetics and family history
• Psychosocial stress, depression, social isolation
• Exposure to air pollution

A blood clot can block blood flow to the brain, causing an ischemic stroke

Signs and Symptoms

Symptoms develop suddenly and may include:

• Numbness or weakness on one side of the body
• Trouble speaking or understanding language
• Vision loss in one or both eyes
• Dizziness or loss of coordination
• Severe headache without known cause

FAST Acronym

• F – Face drooping
• A – Arm weakness
• S – Speech difficulty
• T – Time to call emergency medical services

Complications

Without rapid treatment, ischemic stroke can lead to:

• Brain edema or swelling
• Paralysis or muscle weakness
• Aphasia or language impairment
• Cognitive decline and dementia
• Seizures
• Pneumonia due to swallowing dysfunction
• Urinary incontinence
• Depression and mood disorders
• Deep vein thrombosis and pulmonary embolism

Diagnosis

Evaluation involves:

Physical Examination

• Neurological exam to assess mental status, motor strength, coordination, and cranial nerve function

Imaging

• CT scan – often the first test to rule out hemorrhagic stroke
• MRI – better for detecting ischemic changes
• CT angiography or carotid ultrasound – evaluates vascular blockages

Laboratory Tests

• Blood glucose, CBC, coagulation profile, electrolytes

Cardiac Evaluation

• Electrocardiogram (ECG)
• Echocardiogram to check for cardiac emboli

Treatment

An ischemic stroke is a medical emergency that requires immediate care.

Medications

• tPA (Tissue Plasminogen Activator) – thrombolytic drug given within 3–4.5 hours of symptom onset
• Antiplatelets – such as aspirin or clopidogrel
• Anticoagulants – including warfarin or direct oral anticoagulants (DOACs) for cardioembolic strokes

Surgical/Endovascular Procedures

• Thrombectomy – mechanical removal of the clot
• Carotid endarterectomy – removes plaque from carotid arteries
• Angioplasty and stenting – opens narrowed vessels with balloons and stents

Rehabilitation

Stroke rehabilitation includes:

• Physical therapy – to regain strength and coordination
• Occupational therapy – to relearn daily tasks
• Speech therapy – for communication and swallowing difficulties
• Neuropsychology – for cognitive and emotional support

Prevention

Preventive strategies include:

• Managing blood pressure, blood sugar, and cholesterol
• Stopping smoking
• Healthy diet and regular exercise
• Use of statins, antiplatelets, and anticoagulants when indicated
• Treating atrial fibrillation and sleep apnea
• HPV vaccination and control of chronic infections

Prognosis

Prognosis depends on the severity, timing of treatment, and location of brain damage. Early intervention improves survival and functional recovery. Some individuals may recover fully, while others face lifelong disability.

See Also

• Stroke
• Hemorrhagic stroke
• Transient ischemic attack
• Atherosclerosis
• Neurorehabilitation
• FAST (stroke)
• Cerebrovascular disease