ARCHIVED - Research About - Heart Disease

This page has been archived.

[ PDF (200 KB) | Help ]

The Canadian Institutes of Health Research (CIHR) is the Government of Canada's agency for health research. CIHR's mission is to create new scientific knowledge and to catalyze its translation into improved health, more effective health services and products, and a strengthened Canadian health-care system. Composed of 13 Institutes, CIHR provides leadership and support to nearly 12,000 health researchers and trainees across Canada. Through CIHR, the Government of Canada invested approximately $112.8 million in 2007-08 in cardiovascular disease-related research across Canada.

---

The Facts

• The human heart is a hard-working organ. About the size of a fist, it pumps some 7,500 litres of blood daily.
• While cardiovascular disease was once considered primarily a man’s disease, the number of deaths each year from heart disease and stroke is now virtually the same for women and men. Almost 75,000 Canadians die from it each year.
• Cardiovascular disease is the number one cause of death, but the proportion of deaths it causes has been declining over the past 25 years as the number of cancer deaths has risen. Combined, the two were responsible for about six of every 10 deaths in 2004.
• In Canada, a stroke occurs every 10 minutes, or approximately 50,000 times a year. Less than 50% of stroke survivors return to work.
• According to the Heart and Stroke Foundation, almost all (94%) of first heart attacks in women can be attributed to cigarette smoking, an abnormal ratio of blood lipids, high blood pressure, diabetes, abdominal obesity, stress, not eating enough fruits, not eating enough vegetables and insufficient exercise.

(Source: Statistics Canada, the Heart and Stroke Foundation of Canada, and the Canadian Stroke Network)

Finding Solutions

Beta blockers increase risk of stroke, death

Use of beta blockers by patients undergoing noncardiac surgery has been a standard clinical practice for over ten years. But a major international study has shown that while these drugs may help prevent heart attacks during surgery, they also appear to increase the risk of death and of a major stroke. The POISE (perioperative ischemic evaluation) study, funded in part by CIHR and published in The Lancet, involved more than 8,000 surgical patients in 23 countries. Half received the beta blocker metoprolol succinate, half got a placebo. Metoprolol patients were 27% less likely to suffer a heart attack but were 33% more likely to die and had more than double the risk of a stroke than their placebo counterparts. McMaster University's Dr. P.J. Devereaux was the co-principal investigator for POISE.

New protocol halves cardiac deaths

A new emergency protocol developed by the University of Ottawa Heart Institute is saving lives and relieving emergency room congestion. Ottawa paramedics have been trained to diagnose ST-Elevation Myocardial Infarction (STEMI), a major form of heart attack, and take those patients directly to the Heart Institute where an emergency team provides specialized care. Over one year, deaths from in-hospital heart attacks dropped to less than 5% for Heart Institute patients, down from 10% for patients treated using conventional approaches. As well, emergency room traffic was reduced by 40%. Results of the research and trials, led by Dr. Michel Le May, were published in the New England Journal of Medicine.

Aortic valves improve with new drug

A team at the Montreal Heart Institute Research Centre, led by CIHR-funded scientist Dr. Jean-Claude Tardif, is using a new medication to improve aortic valve narrowing in rabbits. The study involves raising levels of HDL, the so-called "good cholesterol", and has potential application for treating aortic valve stenosis, the most common form of heart valve disease in Western countries. Dr. Tardif said that while clinical studies of patients suffering from the disease need to be done, the drug could provide an alternative to the current practice of cardiac surgery to replace valves damaged by stenosis.

The Researchers

Dr. André Marette – Links in a Triple Health Threat

Obesity. Type 2 diabetes. Heart disease. They're a triple threat that health researchers now see as a single, deadly disease. But what scientists don't see clearly are the genes and molecules that link these conditions.

Dr. André Marette is leading a unique team of Canadian and Finnish researchers that are working to change this. They're tracking the genetic and molecular pathways that make coronary heart disease the most common cause of death in obese patients with type 2 diabetes.

"People who are obese and diabetic develop distinct and more severe cardiovascular problems than others," says Dr. Marette, a professor at Laval University. "The big question is: What is it about the obese diabetic state that makes these people more susceptible to heart disease?"

The study involves a Genome Wide Association Study in which the DNA of more than 1000 Quebec heart patients will be analyzed to find links between gene sequence variations and diabetes-linked cardiovascular disease (CVD).

The study's great strength, says Dr. Marette, is that the researchers will be able to compare the genetic markers they find with a range of clinical measurements collected for each patient. These measurements include patients' levels of deep abdominal fat, something that has been clearly linked to increased risk of type 2 diabetes and CVD.

Dr. Marette says this ambitious project is possible because of an international dream team with complementary strengths. It includes Laval University and University of Toronto researchers, and researchers from the University of Kuopio in Finland. Finns have one of the world's highest rates of type 2 diabetes.

The researchers hope their genetic and molecular sleuthing will soon improve patient treatment.

"Obese diabetic patients with heart disease all respond differently to treatments," says Dr. Marette. "We want to get to a point where we can use a patient's genetic profile to help decide on the best mix of exercise, dietary change or medication for that person."

For more information, go to www.impact.cihr-irsc.gc.ca.