Face drooping, Arm weakness, Speech difficulty, Time to call 000. Sudden numbness, confusion, trouble seeing or walking, or a severe headache can also signal a stroke. Call 000 immediately. Treatment works best when given quickly.
What is an ischaemic stroke?
An ischaemic stroke occurs when the blood supply to part of the brain is suddenly cut off, usually by a clot blocking an artery. Deprived of oxygen, brain tissue begins to die. The longer the blockage lasts, the more brain is lost, which is why stroke care is built around speed: the widely used phrase is that time is brain.
When the blocked vessel is one of the brain's larger arteries, this is called a large vessel occlusion, and it is the situation in which mechanical thrombectomy can make a substantial difference.
How stroke is treated
Two treatments work together in the emergency setting:
- Clot-dissolving medication (thrombolysis), given intravenously within a defined time window to help break down the clot
- Mechanical thrombectomy, a procedure to physically remove the clot from a large artery
Mechanical thrombectomy
Thrombectomy is an emergency endovascular procedure. Through a small puncture in the groin or wrist, a catheter is guided up to the blocked artery in the brain. The clot is then removed, either by capturing it in a stent-like device (a stent retriever) or by aspirating it through a catheter, or both. Restoring blood flow quickly can rescue brain tissue that has not yet died, improving the chance of recovery and reducing disability.
Landmark trials established thrombectomy as standard care for eligible patients with large vessel occlusion, and later trials extended the treatment to carefully selected patients presenting later, using imaging to identify salvageable brain tissue.
Who can be treated
Not every stroke is suitable for thrombectomy. Eligibility depends on where the blockage is, how much brain is already irreversibly damaged, the time since symptom onset, and the person's baseline health. Urgent brain imaging (CT, CT angiography and often CT perfusion) is used to make this assessment rapidly. Because these decisions are time-critical, they are made within the acute stroke service, not through outpatient referral.
Thrombectomy is delivered by the hospital stroke service, with neurology, emergency medicine, radiology and interventional neuroradiology working together around the clock. For anyone with signs of stroke, the single most important action is to call 000 without delay.
After a stroke
Recovery continues well beyond the emergency phase, with rehabilitation and secondary prevention, including investigation of the cause (such as carotid disease or an irregular heart rhythm) to reduce the risk of another stroke. Where a narrowed carotid artery is found, it may itself require treatment.