Progress on stroke prevention

@HealthMed 
Stroke is an increasingly common cause of death and disability worldwide. See the summary below and comments related to our new research report just published online in the major American Heart Association journal Stroke, based on results from the Warwick Carotid Artery Disease Registry. 

See media interest in the research, both in the 'tests for spotting 'minuscule “breakaway” blood clots which usually go undetected' and in this potential new treatment approach. 

Finding and reducing high risk of stroke

Narrowing of carotid arteries in the neck is a very important cause of stroke. A major reason for the increase stroke risk is that the roughened carotid artery surface can trigger formation of small clots that can then dislodge into the brain circulation. These microemboli can block brain arteries to lead to weakness, disturbed speach, loss of vision and other serious stroke syndromes.

Doppler trace: red line shows micro-embolus signal.

A team of scientists at the University Hospital Coventry and University of Warwick led by Vascular Surgeon Professor Chris Imray and Professor of Therapeutics Donald Singer have developed a Carotid Research Group to find new ways to predict and prevent high stroke risk in patients with carotid artery disease. Using ultrasound scanning they are able to detect microemboli to find out which patients are at very high risk of stroke.

The major US journal Stroke has now published a report from Imray and Singer's team with two main findings. Despite single or dual anti-platelet treatment with aspirin and clopidogrel before carotid artery surgery, patients can develop high rates of microemboli. And the team looked at different rescue treatments aimed at stopping these microemboli. The anti-platelet drug tirofiban had previously been shown to be helpful in treating patients with acute coronary artery syndromes. In Stroke, Imray and Singer's team report that with rescue tirofiban there was a large decrease in the half-life of micro-emboli (23 vs. 60 minutes) and in time for these microemboli to be resolved (68 vs. 113 minutes), compared to an alternative treatment using infusion of the clot-preventing polysaccharide dextran-40.

Professor Imray said: 'These findings show the importance of ultrasound testing for micro-emboli in carotid disease patients. These biomarkers of high stroke risk cannot be predicted just from assessing the severity of risk factors such as smoking history, cholesterol, and blood pressure.'

Professor Singer  added 'These findings show that the choice of rescue medicine is very important when carotid patients develop microemboli despite previous treatment with powerful anti-platelet drugs such as aspirin and clopidogrel. We now need to go on to further studies of anti-microemboli rescue treatments, to aim for the right balance between protection and risk for our patients.' 

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