Ischemic Stroke

Ischemic stroke occurs when an artery supplying the brain is occluded, most often by thromboembolism from atherosclerotic plaque, cardiac sources such as atrial fibrillation, or small vessel disease. Roughly 1.9 million neurons die per minute of untreated large vessel occlusion, which is why the entire acute care system is organised around speed. Intravenous thrombolysis is given within 4.5 hours of onset, and mechanical thrombectomy can be effective up to 24 hours in selected patients with salvageable tissue on perfusion imaging. Recognising the FAST signs and calling emergency services immediately, rather than waiting to see if symptoms settle, is the single highest-value action a member of the public can take. Secondary prevention drives long-term outcome. Blood pressure reduction is the most powerful lever, followed by high-intensity statin therapy, antiplatelet treatment or anticoagulation where atrial fibrillation is present, diabetes control and smoking cessation. Atrial fibrillation is frequently paroxysmal and missed, so prolonged cardiac monitoring after cryptogenic stroke changes management in a meaningful proportion of cases. Supplement evidence in stroke is largely cautionary. B vitamins lower homocysteine but the large trials showed limited stroke reduction and no mortality benefit. Omega-3 failed to prevent stroke in major prevention trials. Vitamin E and beta-carotene increased haemorrhagic risk signals. The honest position is that supplements have not replaced any element of proven secondary prevention.

• •Sudden one-sided facial droop
• •Arm or leg weakness on one side
• •Slurred or confused speech
• •Sudden vision loss or double vision
• •Sudden severe imbalance or vertigo
• •Sudden severe headache

• •Atherosclerosis of large arteries
• •Atrial fibrillation
• •Hypertension and small vessel disease
• •Diabetes
• •Smoking
• •Arterial dissection
• •Hypercoagulable states

Large artery atherosclerosis with plaque rupture, cardioembolism from atrial fibrillation or structural heart disease, small vessel lipohyalinosis from hypertension and diabetes, arterial dissection particularly in younger patients, hypercoagulable states, and rarely paradoxical embolism through a patent foramen ovale.