Shining the spotlight on stroke

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The race is on to prevent one of the most debilitating diseases of our time

On Dec. 22 Mike Edwards was thinking about turkey, ham and the holiday season ahead. He had just left the airport after collecting his son, home from Calgary, when the phone call from Sunnybrook came. His 83-year-old mother, Mary Edwards, was in the emergency room suffering a serious stroke.

"We were totally in shock, very upset. I had just left my mother a few hours earlier. She was about to get the vacuum out," he says.

Mrs. Edwards, who was relatively healthy except for high blood pressure, was lucky that she remained conscious after the stroke. Her cries for help caught the attention of a postal woman delivering mail.

"She phoned 911 and stayed with my mom till the ambulance came," Mr. Edwards says. "If not for her being there, things might have been very different."

In cases of hemorrhagic stroke – wherein bleeding into the brain occurs – response time is a critical factor in the outcome for the patient. About 40 per cent of people who have a hemorrhagic stroke die in hospital and most survivors are left severely disabled. Currently, there is no approved medication to stop brain bleeds  from becoming lethal strokes.

Physician researchers at Sunnybrook's Hurvitz Brain Sciences Program are working hard to change this. They are leading the SPOTLIGHT trial, an innovative study headquartered at Sunnybrook Health Sciences Centre and involving 14 hospitals across Canada.

The study is investigating if a promising blood-clotting drug administered quickly to patients in the ER gives them better odds of survival and recovery. Participants are identified by using a new emergency imaging technology to ascertain if they are at high risk of increased bleeding in the brain.  Those deemed eligible are randomly assigned to receive  an injection of the study  drug or a placebo.

While Mrs. Edwards was travelling by ambulance to Sunnybrook, the hospital's 24/7 "Code Stroke" protocol was activated. This alerted stroke specialist Dr. David Gladstone, neurologist and principal investigator of the SPOTLIGHT trial, who rushed in to treat her. Her brain scan revealed a serious bleed.

"She was in the midst of a severe stroke. Her left side was becoming paralyzed. Her blood pressure was very high," Dr. Gladstone recalls.

Mrs. Edwards was treated as part of the SPOTLIGHT study protocol. Her brain bleeding stopped and she is now making a remarkably good recovery.

The trial builds upon what was a eureka moment for Sunnybrook neuroradiologist Dr. Richard Aviv, who is co-principal investigator of the study. In 2007 Dr. Aviv uncovered the "spot sign," indicative of a growing bleed, using a special CT scan technique that visualizes bleeding blood vessels in the brain.

"The spot sign method has become the most rapid, accurate and reliable way to predict which patients are actively bleeding and at highest risk of worsening due to hemorrhage expansion," says Dr. Aviv.

The SPOTLIGHT trial, funded by the Canadian Institutes of Health Research and others,  is the first Canadian study to test the therapy in patients specifically selected using CT angiography because they have the spot sign. Image-guided therapeutics is a major theme within the Hurvitz Brain Sciences Program at Sunnybrook.

"There is a pressing need for this kind of multidisciplinary stroke research," notes Dr. Gladstone. "Stroke is the second leading cause of death in adults worldwide, and we must develop new approaches to improve stroke prevention, treatment and rehabilitation." For years, brain bleeds have been considered an untreatable type of stroke, with a dismal prognosis. If this new treatment approach proves successful in carefully conducted studies, then it could revolutionize how such patients are treated.

Meanwhile, the most significant advance in emergency stroke treatment in the last 20 years has emerged from the recently completed international clinical trial ESCAPE, headquartered in Calgary.

Results from the ESCAPE trial will change how ischemic strokes – strokes that occur when an artery to the brain is blocked – are treated, says Dr. Rick Swartz, an investigator on the research team and the medical director of the Stroke Program at Sunnybrook Health Sciences Centre, one of the study sites for the trial.

The essence of the trial, says Dr. Swartz, was to find a way to quickly break down large blood clots blocking the blood supply to the brain. Trial sites in Canada and around the world selected patients with moderate to severe stroke, deemed to have brain tissue left to save.

"Advanced imaging allows us to see if there is blood getting through to the brain, so we can select people who are likely to have enough time to reopen the artery and make a difference," Dr. Swartz explains.

The procedure used is called endovascular treatment (ET), whereby doctors insert a retrievable thin tube, or stent, through an artery in the patient's groin, guiding it with X-ray imaging through blood vessels to the brain.

Once it's in the brain, the stent grabs onto the clot and pulls it out.

The treatment has been shown to cut death rates in half. There is also a higher chance of recovery and less impairment.

"Sometimes you could tell right away that it was working," says Dr. Swartz. "As the procedure was finishing, the patient was already moving an arm." The findings from ESCAPE will influence Canada's stroke best-practice guidelines, making Canada one of the first countries in the world to incorporate the treatment into their guidelines.

This is the fifth in a six-part series about the future of brain sciences.  Visit sunnybrook.ca/brain for more information.

This content was produced by The Globe and Mail's advertising department, in consultation with Sunnybrook. The Globe's editorial department was not involved in its creation.