Calgary Stroke Program continues to revolutionize the prevention and treatment of stroke
Worldwide, 15 million strokes occur each year — there is one every nine minutes in Canada. The results can be devastating. When someone experiences a stroke, the sudden loss of blood flow causes a region of the brain to die, which can permanently affect speech, vision, balance and movement. Every minute without care can impact a person for the rest of their life.
Citizens of Southern Alberta have access to the Calgary Stroke Program, a collaboration between the Cumming School of Medicine’s (CSM) Hotchkiss Brain Institute (HBI), the Department of Clinical Neurosciences (DCNS) and Alberta Health Services. It has integrated stroke care starting with the 9-1-1 call, to treatment and rehabilitation. The program’s revolutionary approach and landmark clinical trials have changed the way many strokes are treated in Canada and around the world.
“We’ve increased the chances of surviving and also limited disability from stroke in this country and beyond,” says Dr. Andrew Demchuk, MD, director of the Calgary Stroke Program and an associate professor in the DCNS, as well as a member of the HBI. “We’ve done this by continuously applying the results from stroke research to real-life clinical stroke care.”
A stroke happens when blood stops flowing to any part of the brain, damaging brain cells. The effects depend on the part of the brain that was damaged and the amount of damage done.
A University of Calgary-led international study highlights the importance of magnetic resonance imaging (MRI) in helping to diagnose minor stroke and transient ischemic attacks (TIAs) — a temporary period of symptoms similar to those of a stroke that usually lasts only a few minutes and doesn't cause permanent damage. Often called a “mini-stroke,” a TIA can be an impending warning sign of a major, devastating stroke.
The study, Diagnosis of Uncertain-Origin Benign Transient Neurological Symptoms (DOUBT), analyzed patients who experienced a number of symptoms that aren’t always associated with stroke — such as numbness, dizziness, or very short episodes of weakness or difficulty with speech.
Principal investigator Dr. Shelagh Coutts, MD, a neurologist at the Foothills Medical Centre (FMC), a professor in the departments of Clinical Neurosciences, Radiology and Community Health Sciences, and a member of the HBI, says that, because the risk of stroke increases after a first TIA, it’s important that physicians are certain of the diagnosis in low-risk cases with non-traditional symptoms.
“If you don't have motor and speech symptoms, the diagnosis is a lot less clear,” explains Coutts. “Patients with numbness, dizziness or difficulty walking may not be diagnosed with a stroke syndrome. Overall, these patients are felt to be at low-risk of having a stroke.”
Physicians involved in the study examined patients within eight days of the start of their symptoms. They performed a detailed neurological assessment, took a patient history, made a diagnosis and completed an MRI scan within the first week — followed by a second diagnosis. In 30 per cent of patients in the study, physicians changed their diagnosis based on the MRI scan.
“That's not just to change patients to having a stroke,” says Coutts. “There's also the reverse where we thought they might have had a stroke or TIA but, based on a negative MRI scan and other clinical symptoms, we decided it wasn't. For patients whose MRI is negative, knowing they haven’t suffered a stroke can be very reassuring.”
Preserving brain cells
Another UCalgary-led international study shows that an experimental neuroprotective drug, nerinetide, helps to preserve brain cells for a time after stroke.
Dr. Michael Hill, MD, a neurologist at the FMC and professor in the departments of Clinical Neurosciences, Radiology, Medicine and Community Health Sciences, and Dr. Mayank Goyal, MD, PhD, a neuroradiologist at the FMC and professor in the departments of Radiology and Clinical Neurosciences, led the team of stroke researchers in a clinical trial which shows that treating acute ischemic stroke patients with nerinetide, combined with a surgical procedure to remove the clot, improves patient outcomes by promoting brain cell survival.
“The study provides evidence of a biological pathway that protects brain cells from dying when they are deprived of blood flow,” explains Hill, who is a member of the HBI, the Libin Cardiovascular Institute and the O’Brien Institute for Public Health. “Nerinetide targets the final stage of the brain cell’s life by stopping the production of nitric oxide within the cell...the neuroprotection that we’ve seen opens the door to a new way of treating stroke.”
Images of patients’ brains from the study show the expected size of the damage from the stroke is sizeably reduced when nerinetide is administered and the clot retrieval procedure is performed.
“Many studies investigating neuroprotective drugs have been conducted and have failed, so we’re extremely excited by these results,” says Goyal, who is also an HBI member. “While nerinetide is not approved for use yet, it shows the potential of a new tool to promote recovery from stroke.”
The results in the nerinetide study, called the ESCAPE-NA1 Trial, build on the success of the ESCAPE trial, in which the Calgary Stroke Program proved that a clot-retrieval procedure known as EVT (endovascular treatment) can dramatically improve patient outcomes after an acute ischemic stroke. The researchers are now leading a third study, ESCAPE-NEXT, to confirm the exciting results of ESCAPE-NA1. Read more about the ESCAPE-NA1 Trial, including the trial results published in The Lancet.
An ischemic stroke occurs when a blood clot blocks the blood flow in an artery within the brain.
Personalizing stroke care
Stroke is a complex and diverse disease with no single treatment of benefit to all patients. The Calgary Stroke Program uses novel imaging techniques to deliver quick, accurate and personalized stroke care — a diagnosis and treatment plan tailored to the individual patient.
When someone arrives at the hospital showing signs of a stroke, every minute counts. The current diagnostic approach for stroke can include as many as three steps. Created by UCalgary researchers, the Simple Perfusion Reconstruction Algorithm (SPIRAL) is based on just one computerized tomography scan (CT or CAT scan), and locates the blockage without the use of contrasting dyes.
“What we’ve developed will allow more Canadian stroke centres to conduct endovascular procedures in the future,” says Dr. Philip Barber, MD, a neurologist at the FMC, who is an associate professor in the departments of Clinical Neurosciences, Radiology and Community Health Sciences, and a member of the HBI. “By avoiding the additional scans that are currently required, there are many advantages in terms of time and cost savings. This new technology is a significant innovation.” Learn more about SPIRAL, including the published findings in the American Journal of Neuroradiology.
Working as a team
The Calgary Stroke Program builds on the skills of an interdisciplinary team of individuals who work diligently to advance stroke treatment through research, education and patient-centred care.
“A patient who has had a stroke relies on the efforts of a team,” says Dr. Demchuk. “We have a team of dedicated clinician scientists; basic, imaging and computer scientists; engineers; statisticians; epidemiologists; and management experts, working in parallel to change lives. We are leading trials and investigations that are advancing stroke treatment throughout the world, and it is a huge team effort.”
Training stroke specialists
Perhaps the Calgary Stroke Program’s greatest shared success is the training of stroke specialists.
The internationally recognized Calgary Stroke Fellowship Program has trained more than 100 stroke physicians from more than 20 countries, helping them to become stroke champions in their geographic areas. The global impact of this training has transformed stroke care in countries throughout the world such as India, Germany, Saudi Arabia, Spain, Australia, the Philippines and the United Kingdom.
“A significant strength of the program is the diversity of fellows that we have,” says Dr. Bijoy Menon, MD, a neurologist at the FMC, an associate professor in the departments of Clinical Neurosciences, Radiology and Community Health Sciences, and a member of the HBI. “People come into the program with very diverse educational backgrounds and have the opportunity to share their experiences in an environment where questioning and challenging is encouraged.”
Fellows train within an integrated stroke management team made up of stroke neurologists, researchers and specialized health-care personnel. These experts provide comprehensive integrated services in the areas of acute stroke, stroke management, stroke rehabilitation, stroke prevention and stroke research.
"Another huge strength of the fellowship program is research," says Menon. "Fellows participate in the design, execution, and implementation of many clinical trials and studies that investigate diagnosis, prevention, cognitive impairment and rehabilitation. We're really proud of the education we're able to provide through our world-class combined clinical and research program model."
Calgary Stroke Program Team Members
About the Hotchkiss Brain Institute
The Hotchkiss Brain Institute (HBI) at the University of Calgary consists of more than 120 scientists and clinician-scientists who are dedicated to advancing brain and mental health research and education. The Institute’s research strengths, in the areas of Brain and Behaviour, Neural Injury and Repair, and Healthy Brain Aging, are leading to new treatments for neurological and psychiatric disorders, aimed at improving quality of life and patient care.
Led by HBI, Brain and Mental Health is one of six research strategies guiding UCalgary in its Eyes High strategy: providing a unifying direction for brain and mental health research and positions researchers to unlock new discoveries and treatments for brain health in our community.