CardioLink Clinical Trials Canada

Changing practice. Changing lives.

CardioLink Canada is the first research program worldwide with a focus on clinical trials in heart and vascular surgery. A cutting edge research program through the Cardiovascular and Diabetes research program of St. Michael’s Hospital, CardioLink was developed to find answers to important unanswered questions in the areas of atrial fibrillation, aortic aneurysms, peripheral arterial disease, valvular heart disease and community-based interventions to reduce re-hospitalization.

Our goal for these transformative research studies is to provide real solutions for these cardiovascular conditions. Solutions with impact. Solutions that matter to our patients and their families.

Key Statistics


Brain cells die every minute after stroke (Heart & Stroke, 2015)


Every 7 minutes in Canada, someone dies from heart disease or stroke (Statistics Canada, 2011)


Cost of cardiovascular disease costs the Canadian economy ($ Billions) each year

About CardioLink

Dr. Subodh Verma, a Cardiovascular Surgeon with St. Michael’s Hospital, was troubled by the lack of data available to help guide his decision making and treatment choices for patients undergoing heart or vascular surgery. Researchers are experts in their field, but they’re not all experts in designing clinical trials or observational studies. Not all ideas are good ideas and not all research is good research – and he wanted to help change that.

“There are still too many unknowns when it comes to cardiovascular surgery outcomes and clinical translational research has the potential to be transformative for our patients and improve their heart health,” said Dr. Verma. “I think the best way to find those missing links is by connecting smart people and asking smart questions.”

In response, Dr. Verma partnered with Dr. Muhammad Mamdani, an expert in the development of clinical trials and observational studies and Dr. David Mazer, an expert in cardiac physiology and metabolism and perioperative organ protection, to develop CardioLink Canada.  CardioLink Canada connects cardiometabolic researchers from across Canada with experts in clinical trial design, population epidemiology, and knowledge translation.

“Our experts work with researchers to ensure that research is relevant to the needs of the clinical community, policy makers, and patients.” said Dr. Mamdani. “We’re helping researchers develop studies that are truly impactful.”

Through the development and implementation of well-designed, randomized trials and observational studies, as well as strategies to effectively share results with knowledge users, the vision of the CardioLink program is to bring about changes in practice – reducing morbidity and improving the lives of patients.

Featured Clinical Trials

SEARCH-AF (Post-Surgical Enhanced Monitoring for Cardiac Arrhythmias and Atrial Fibrillation)

Atrial fibrillation (AF) is a cardiovascular condition involving an irregular heart rhythm and affects approximately 350,000 Canadians (Heart & Stroke Foundation, 2015). SEARCH-AF is a randomized controlled trial that follows almost 400 AF patients over a 2 ½ year period. This trial was designed to determine whether identifying new occurrences of atrial fibrillation in patients following heart surgery by conducting intensive and extended cardiac rhythm monitoring with a novel adhesive device, will help identify individuals at risk of having a stroke following heart surgery

ACE (A Randomized Controlled Trial of Axillary vs. Innominate Artery Cannulation for Antegrade Cerebral Protection in Aortic Surgery)

The ACE trial looks to challenge the way complex aortic surgery is approached.  One of the perils of such surgical procedures is the need to put the patient in deep hypothermic circulatory arrest – a cooling of the body and the stoppage of blood flow.  While essential for these surgeries, it is widely recognized that extended duration of hypothemic circulatory arrest risks damage to the brain.  The aim of the ACE trial is compare an innovative surgical technique to the established methodology with regards to both safety and efficacy endpoints.  This trial has the potential to alter the practice of aortic surgery worldwide and improve patient outcomes.

CAMRA-1 (A randomized trial of mitral valve repair with leaflet resection versus leaflet preservation on functional mitral stenosis: The Canadian Mitral Research Alliance Trial)

The mitral valve is the critical interface between the left ventricle and left atrium that prevents backflow of blood in the heart. Malfunction of this valve (mitral stenosis) negatively impacts clinical outcomes and often necessitates surgical intervention to restore lost functionality.  Two surgical strategies, “leaflet resection” and “preservation repair”, are techniques that have been used extensively to repair the mitral valve, but little research has been carried out to address the fundamental question of which strategy has better outcomes for patients.  CAMRA-1 will seek to directly assess the strengths and weaknesses of each technique with a critical assessment of how these outcomes can improve patient outlook.   By comparing the two different ways to repair the mitral valve, CAMRA-1 seeks to help usher in a new evidence-based era of standardized mitral valve repair.


More and more patients are now having minimally invasive valves placed, a procedure often called TAVR or TAVI. Could a blood thinner prevent the deterioration of these valves and prevent complications from valve failure? CardioLink’s VALVECLOT study is trying to solve this problem by developing an international effort aimed at studying TAVR and other biological valves used during heart surgery.

EXTINGUISH (A Randomized Trial of Systemic Inflammation Reduction with Colchicine in Critical Limb Ischemia)

Critical limb ischemia (CLI) is a severe form of artery disease outside of the heart that can block blood flow and ultimately lead to death or limb amputation.  Novel therapies to reduce risk in these patients are desperately needed, and there are no trials in this specific population that are currently ongoing.  The EXTINGUISH Trial was established to address this critical need.  The underlying cause of CLI is atherosclerosis which a hardening of the arteries now believed to be an inflammatory disorder.  The EXTINGUISH trial will examine if a simple anti-inflammatory pill taken once or twice daily will reduce potentially severe outcomes associated with this vascular disorder.  The results of this trial may provide a simple yet effective strategy that can be immediately implemented to improve the lives of patients suffering from CLI.

ENABLE (Randomized trial of a nurse-practitioner led intervention to reduce the risk of readmission following vascular surgery)

Rates of readmission following surgery can serve as a marker for quality of care provided by clinicians and hospitals.  In a recent study of ~500,000 operations identified in the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database, the rate of 30-day admission was highest following vascular surgery in the lower extremities.  Among these, the most common cause of readmission is infection at the surgical site, which may be preventable with early detection and management.  The ENABLE Trial seeks to bridge this gap following vascular surgical procedures with a structured nurse-practitioner led program. The primary aim of this study is to determine whether a nurse-practitioner intervention program will reduce the risk of 30-day readmission following vascular surgery, and improve the quality of care received by these patients.  If successful, this could represent the first step in a new paradigm of post-operative patient care.


Cardiovascular disease is the main cause of death and disability in patients with diabetes. Recently some medications, called SGLT2 inhibitors, have been shown to reduce mortality in people with diabetes and heart disease. However, the mechanism through which this occurs remains completely unknown. CardioLink is trying to find that answer. Through a study called EMPA-HEART, we will evaluate all of the major biological processes at the level of heart, brain and kidney to explore how the diabetes medication, empagliflozin, prevents death in diabetes. Through studying heart structure and function using advanced MRI techniques, we will try to understand the molecular cues that are affected – these insights may help us better understand the reasons why people with diabetes have such high rates of heart disease and stroke.


To find out more about CardioLink, please contact:

Adrian Quan, MPhil

Program Coordinator
416-864-6060 ext. 77457