Bedros Kashkarian is happy to be alive, and he credits Sunnybrook neurologist Dr. David Gladstone and his potentially life-saving stroke research for keeping him that way.
One Saturday in February, Bedros was serving a customer at his retail store in North York, Ont., when he suddenly had trouble speaking coherently. While the episode only lasted about a minute and nothing like it had ever happened before, it concerned the 67-year-old enough to see his family doctor that Monday, who referred him to Sunnybrook. Dr. Gladstone saw Bedros the following day at Sunnybrook's recently expanded Rapid TIA Clinic within the hospital's Regional Stroke Centre.
The clinic, specializing in stroke prevention, gets patients fast-track access to state-of-the-art diagnostic tests of the brain, heart and the blood vessels. Bedros was diagnosed with a "transient ischemic attack" (TIA) or mini-stroke, which is often a forerunner of a larger stroke. But all his tests came back normal. Dr. Gladstone, who has been researching such strokes of unknown cause for years, is principal investigator of the world's largest randomized clinical trial of advanced heart monitoring in stroke patients. The $1.7-million Canadian Stroke Network-funded EMBRACE trial recently completed. The findings revealed that one in six people with an unexplained stroke TIA has silent atrial fibrillation, a potentially dangerous irregular heart rhythm that can lead to more strokes if left untreated. The findings of the major 16-centre Canadian study were published in the prestigious New England Journal of Medicine in June.
One of the big challenges in stroke medicine is that one in every four strokes is "cryptogenic," meaning its cause can't be pinpointed. The EMBRACE trial studied 572 patients aged 55 and older who had experienced a recent stroke or mini-stroke of unknown origin and in whom standard heart monitoring had failed to detect atrial fibrillation. Participants were randomized into two groups: The first received an additional 24 hours of standard monitoring, and the second received a new strategy of continuous monitoring for 30 days at home using a high-tech chest electrode belt that automatically detects episodes of atrial fibrillation.
In the trial, the prolonged heart monitoring strategy picked up a new diagnosis of atrial fibrillation in 16 per cent of patients, compared to a mere 3 per cent of those who only received standard monitoring. The enhanced detection of atrial fibrillation led to significantly more patients being prescribed stronger anti-clotting medications to better prevent recurrent strokes. The trial, led by Sunnybrook and co-ordinated at the Li Ka Shing Knowledge Institute of St. Michael's Hospital, is an example of successful research collaboration across the University of Toronto.
Prevention of strokes due to atrial fibrillation is a "global public health issue," according to the study. Atrial fibrillation is a risk factor for stroke because it can promote the formation of blood clots in the heart that can travel to the brain. It's important to detect because it can be effectively treated with certain anti-clotting medications, which drastically reduce the risk of more strokes.
With the EMBRACE trial findings in hand, Dr. Gladstone sent Bedros home with one of the new high-tech heart monitors, which he wore 24-7 for two weeks and revealed that he had a 12-hour-long episode of atrial fibrillation. Based on this result, Dr. Gladstone was able to prescribe stronger anti-clotting medication that he'll take daily for the rest of his life to prevent further strokes.
"This is practice-changing research," says Dr. Gladstone. Based on the results of the trial, we've literally changed our Sunnybrook stroke clinic protocols overnight to provide enhanced patient care." "These research findings represent a major clue in solving the mystery of cryptogenic strokes. We have found a highly effective strategy for improving the detection of atrial fibrillation in stroke patients that we hope will translate into many more recurrent strokes prevented."
Next steps will include testing the value of the new high-tech heart monitoring for atrial-fibrillation screening in the healthy general elderly population aiming to prevent strokes from happening in the first place. Dr. Gladstone is launching the new study called SCREEN-AF this fall, which will be conducted as part of the Canadian Institutes of Health Research-funded Canadian Stroke Prevention Intervention Network in partnership with the Population Health Research Institute at McMaster University in Hamilton.
Sunnybrook's stroke specialists are leading the way in stroke research that has immediate applications for improving patient care globally. Based on his recent experience, Bedros has become one of Dr. Gladstone's biggest advocates. "Today I feel great," he says. "I'm here because of the important work Dr. Gladstone's team is doing and because he didn't give up trying to find out what caused my stroke."
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.