Overview
A stroke occurs when the blood supply to part of the brain is suddenly interrupted, causing brain cells to die within minutes. There are two main types: ischaemic stroke (85%, caused by a blood clot) and haemorrhagic stroke (15%, caused by a burst blood vessel). Stroke is a medical emergency. Time is brain: every minute without treatment, 1.9 million brain cells die.
How common is it?
About 100,000 strokes occur in the UK each year — one every 5 minutes. Stroke is the fourth leading cause of death and the leading cause of long-term adult disability in the UK. There are 1.3 million stroke survivors living in the UK.
Causes and risk factors
Ischaemic stroke results from thrombosis (in-situ clot) or embolism (clot from elsewhere, usually the heart or carotid artery). Haemorrhagic stroke results from rupture of a blood vessel due to hypertension, aneurysm, or AVM.
Common risk factors
- High blood pressure (single most important modifiable risk factor)
- Atrial fibrillation (5-fold increased stroke risk)
- High cholesterol and atherosclerosis
- Smoking
- Diabetes
- Obesity and physical inactivity
- Previous TIA or stroke
- Family history
- Age
- Cocaine and amphetamine use (haemorrhagic stroke)
Symptoms
- FAST: Face drooping on one side; Arm weakness (cannot hold both arms up); Speech slurred or difficulty finding words; Time to call 999
- Additional symptoms: sudden severe headache (worst of life — haemorrhagic), sudden loss of vision in one or both eyes, sudden dizziness, loss of balance, or coordination problems
- All symptoms are sudden in onset — this distinguishes stroke from other conditions
When to see a doctor
Call 999 immediately for any FAST symptoms. Do not wait to see if symptoms improve. TIA (mini-stroke — symptoms fully resolve within 24 hours) requires same-day assessment at a TIA clinic or emergency department. ABCD2 score guides urgency.
Diagnosis
CT head immediately to distinguish ischaemic from haemorrhagic stroke (critical for thrombolysis decision). CT or MRI angiography for vessel imaging. ECG for atrial fibrillation. Echocardiogram for cardiac source. Carotid Doppler for carotid stenosis.
Treatments
Thrombolysis (IV alteplase)
Clot-dissolving drug given intravenously for ischaemic stroke within 4.5 hours of symptom onset (or last time seen well). Improves outcomes with 1 in 8 patients having less disability as a direct result.
Thrombectomy
Mechanical removal of the clot using a stent-retriever via catheter through the groin. Can be used up to 24 hours after onset for large vessel occlusion. Produces dramatically better outcomes than thrombolysis alone — NICE-recommended.
Stroke unit care
Specialist multidisciplinary stroke unit care with early mobilisation, physiotherapy, speech therapy, and occupational therapy improves survival and function regardless of stroke type. Reduces mortality by 25%.
Secondary prevention
Antiplatelet agents (aspirin+clopidogrel initially, then clopidogrel alone) for ischaemic stroke. Anticoagulation for AF-related stroke. Statin, antihypertensive therapy, and carotid endarterectomy for severe carotid stenosis.
Self-care and lifestyle
- Control blood pressure rigorously — the most important secondary prevention measure
- Stop smoking immediately after a stroke or TIA
- Take all prescribed medications consistently
- Attend stroke rehabilitation — the brain has significant plasticity and improvements can continue for years
Prevention
Treating hypertension, anticoagulating atrial fibrillation, not smoking, managing diabetes and cholesterol, and regular exercise are the most effective preventive measures. Know the FAST symptoms.