Timely surgery dramatically reduces stroke risk for people with carotid stenosis

Surgical intervention to remove narrowing in the carotid artery (carotid endarterectomy) could substantially reduce the risk of major strokes in certain groups of patients if it is done sufficiently soon after a “warning stroke” or transient ischaemic attack (TIA), suggest authors of a UK study in this week’s issue of THE LANCET.

Peter Rothwell from the University of Oxford, UK, and colleagues analysed pooled data from two trials (the European Carotid Surgery Trial and North American Symptomatic Carotid Endarterectomy Trial) to assess the risk of stroke without surgery, the risk of stroke and death due to surgery, and the overall benefit from surgery.

Data for around 5900 people were available from the two trials. Benefit from surgery was greatest in men, patients aged 75 years or older, and those randomised within 2 weeks after their warning stroke, and fell rapidly with increasing delay.

Dr Rothwell comments: “Benefit is particularly dependent on the delay to surgery after the presenting event. Ideally, the procedure should be done within 2 weeks. Unfortunately, in the UK and elsewhere, the operation is often not done until several months after the event – even if the patient seeks medical attention immediately after their warning stroke. Benefit from surgery is very much reduced at this time, and many patients who would have benefited have their major stroke whilst waiting for surgery.”

The need for urgent investigation and treatment stems from the high risk of major stroke in the first few days and weeks after a TIA or warning stroke. Dr Rothwell adds: “There is therefore a need to educate the public about the symptoms of warning strokes and TIAs so that people seek medical attention immediately. The importance of this latest study is that it shows that many more strokes can be prevented if treatment is initiated early. The problem currently in the UK, and in many other countries, is that we are just not set up to investigate and treat patients sufficiently quickly”.