Researchers find new therapy benefits stroke patients

February 11, 2015 (Toronto, ON) – Researchers have shown that a clot retrieval procedure, known as endovascular treatment (ET), can dramatically improve patient outcomes after an acute ischemic stroke by reducing the overall death rate by 50 percent and significantly reducing disability in survivors.

“The results from this trial will change how stroke is treated in Canada and around the world,” says Dr. Rick Swartz, an investigator on the research team and Medical Director of the Stroke Program at Sunnybrook Health Sciences Centre, one of the study sites. “This is the most significant advance in emergency stroke treatment in the last 20 years, and Canada will be one of the first countries to incorporate this treatment into Stroke Best Practice Guidelines.”

The results of this international randomized controlled trial, led by researchers at the University of Calgary’s Hotchkiss Brain Institute (HBI), were published in the Feb. 11 online edition of the New England Journal of Medicine (NEJM).

Overall, positive outcomes for patients increased from 30 per cent to 55 per cent. In many cases, instead of suffering major neurological disability, patients went home to resume their lives. The overall mortality rate was reduced from two in 10 patients for standard treatment of care to one in 10 patients – a 50 per cent reduction with ET.

The clinical trial, known as ESCAPE (Endovascular treatment for Small Core and Anterior circulation Proximal occlusion with Emphasis on minimizing CT to recanalization times), shows there is a marked reduction in both disability and death among patients who receive ET for acute ischemic stroke. Ischemic stroke is caused by a sudden blockage of an artery to the brain that deprives the brain of critical nutrients, such as glucose and oxygen. Currently, the international standard of care based on Canadian, U.S. and European guidelines is to administer a drug called tPA when appropriate. Known as a ‘clot buster’, the drug dissolves the blood clot.

In the ESCAPE trial, 316 patients who fit the criteria for ET and arrived for treatment within 12 hours of their stroke were randomized to standard medical care (which included the clot-busting drug tPA where appropriate) or standard medical care plus ET.

ET is performed by inserting a thin tube into the artery in the groin, through the body, and into the brain vessels to the clot. This is done under image-guided care using an X-ray. The clot is then removed by a retrievable stent and pulled out, restoring blood flow to the brain.

“As a stroke clinician, this is an exciting time as this therapy provides us with a new option to stop stroke in its tracks as quickly and effectively as we can when the patient first arrives in the Emergency Room,” adds Swartz, also the Director of the University of Toronto Stroke Program. “It further emphasizes how important it is for people to recognize the signs of stroke and call 911 immediately for severe weakness, speech problems or other sudden loss of function. We now have more treatment options, but people must get to the Emergency Room fast.”

Endovascular treatments were first developed in the 1990s, but ET has only recently been technically possible. The ESCAPE team says the success of the trial can be credited to very fast treatment and the use of brain and blood vessel imaging. In ESCAPE, researchers were on average two hours faster in opening the blocked blood vessels than in previously reported trials.

ESCAPE is the second ET trial that demonstrates the efficacy of the treatment and the first trial to demonstrate reduced mortality. The previous trial, known as MR. CLEAN (Multi center Randomized Clinical trial of Endovascular treatment for Acute ischemic stroke in the Netherlands), was published in December 2014.

The study included 22 sites worldwide and patients in the U.S., U.K., Ireland and South Korea. Canada had 11 participating hospitals and enrolled two-thirds of the patients.

In addition to being published online, the results of this landmark study will be published in the March 19 print edition of NEJM and presented at the American Heart Association’s International Stroke Conference in Nashville, Tenn.

The study was funded by The Heart and Stroke Foundation of Canada, Alberta Innovates-Health Solutions and Medtronic, along with generous donations to the HBI Stroke Team and the Calgary Stroke Program.

-30-

SITES

Foothills Medical Centre, Calgary, Alta.
Royal University Hospital, Saskatoon, Sask.
Colorado Neurological Institute, Denver, Colo.
St. Michael's Hospital, Toronto, Ont.
UPMC Medical Centre, Pittsburgh, Penn.
Queen Elizabeth II HSC, Halifax, N.S.
Toronto Western Hospital, Toronto, Ont.
University of Alberta Hospital, Edmonton, Alta.
Chattanooga Center for Neurologic Research, Chattanooga, Tenn.
CHUM-Hospital Notre-Dame, Montreal, Que.
MUSC-Medical University of South Carolina, Charleston, S.C.
Sunnybrook Health Sciences Centre, Toronto, Ont.
Ottawa Hospital, Ottawa, Ont.
London Health Sciences Centre, London, Ont.
McGill University (MNI), Montreal, Que.
Beaumont Hospital, Dublin, Ireland
Abington Memorial Hospital, Abington, Penn.
Royal Victoria Hospital, Belfast, N. Ireland
Yonsei University (Severance Hospital), Seoul, South Korea
Samsung Medical Centre, Seoul, South Korea
Keimyung University (Dongsan Medical Centre), Daegu, South Korea
Temple University, Philadelphia, Penn.

Join the conversation on Twitter #ESCAPEstroke

Learn more about ESCAPE at: http://cumming.ucalgary.ca/escape-stroke (website live on Feb 11 at 12 pm ET)

Media contact
Nadia Radovini
Communications Advisor, Sunnybrook Health Sciences Centre
416.480.4040
nadia.radovini@sunnybrook.ca

University of Calgary- Media Contact
Marta Cyperling
Media Relations Manager, Cumming School of Medicine
403.210.3835
marta.cyperling@ucalgary.ca