A major new international study involving Irish scientists has led to ‘the most significant development in stroke treatment in the past 20 years', it has been claimed.

The findings of the study look set to revolutionise stroke treatment and could reduce stroke-related mortality rates by as much as 50%.

The study, which involved scientists from the Royal College of Surgeons in Ireland (RCSI) and Dublin's Beaumont Hospital, focused on a clot retrieval procedure known as endovascular treatment (ET).

Every year in Ireland, some 10,000 people suffer a stroke and 2,000 people die as a result. Thousands more are left with stroke-related disabilities. However, the study found that the use of ET led to a significant improvement in patient outcomes and a reduction in stroke-related disability and death.

A stroke occurs when the blood supply to the brain is interrupted, depriving it of oxygen. As a result, some of the brain cells die and others are damaged. One in six people will have a stroke at some stage in their life and 80% are known as ischaemic strokes. These are strokes caused by a sudden blockage in the blood vessels supplying the brain, by a blood clot.

The study was carried out at 22 sites around the world, including Beaumont Hospital where patients were referred from 10 centres across Ireland.

It focused on those who had suffered an ischaemic stroke and found that positive outcomes for patients receiving ET increased from 30% to 55%. Many patients who would normally have suffered major neurological disability as a result of their stroke were instead able to go home and get on with their lives.

Furthermore, the overall mortality rate among patients receiving this treatment fell by 50%.

"The results of this study represent the most significant development in stroke treatment in the past 20 years and will impact stroke care in Ireland and around the world. This treatment has the potential to improve survival rates and quality of life of more than 15 million people worldwide who suffer a stroke each year," explained the Irish study's co-lead and consultant stroke physician at Beaumont, Prof David Williams.

However, he emphasised that while this new treatment is improving patient outcomes, time is still of the essence when it comes to stroke.

"When removing a clot with this new treatment, as with existing treatments, every minute matters. If you suspect someone is having a stroke, call 999 immediately as many stroke treatments only work if administered within a set period of time. The tell-tale signs of stroke are facial drooping, inability to raise arms over their heads and slurred speech," Professor Williams noted.

Beaumont Hospital was the second largest patient recruiting site in this worldwide study, with 34 patients taking part over a six-month period.

"There was impressive collaboration between stroke centres, doctors and nurses, and transport services, as well as the radiology team in Beaumont where all the procedures were performed," commented the study's co-lead and consultant neuroradiologist at Beaumont, Dr John Thornton.

Currently and where appropriate, stroke patients are given what is known as a ‘clot buster' - a drug that dissolves the blood clot. As part of this study, 316 patients worldwide, who had arrived at hospital within 12 hours of their stroke, were given either standard medical care, which included clot busting drugs where appropriate, or standard medical care plus ET.

With ET, a thin tube is inserted into the artery in the groin, through the body, and into the brain vessels to the clot. Using an x-ray to guide it, the clot is then removed by a retrievable stent and pulled out. This restores blood flow to the brain.

While this type of treatment was developed back in the 1990s, it has only been technically possible in recent times.

Commenting on the groundbreaking study, Chris Macey of the Irish Heart Foundation said that these findings could enable people throughout Ireland ‘not just to survive stroke, but to get their lives back in the aftermath on a scale that just hasn't been possible in the past'.

However he added that this would only be possible with ‘the requisite investment in our national stroke services'.

Details of these findings are published in the New England Journal of Medicine.