An Alberta research team is making significant advances in recognizing and treating the least understood and toughest-to-diagnose form of heart failure.
Diastolic heart failure occurs when the heart fails to fill with enough blood because the heart muscle has become stiff. About 40 per cent of heart failure patients – roughly 32,000 Albertans – have diastolic heart failure but it can only be confirmed through diagnostic imaging exams, such as echocardiography or magnetic resonance imaging (MRI) scans.
Its symptoms – including chest pain, fatigue, weakness and swelling – are similar to those caused by the more common type of heart failure, systolic, which occurs when the heart muscle becomes too weak to pump with enough force.
“Diastolic heart failure looks like systolic heart failure when you’re examining someone at the bedside,” says Dr. Jonathan Howlett, director of Heart Failure at the Libin Cardiovascular Institute of Alberta and clinical professor of Medicine at the University of Calgary. “We’re trying to learn more about it so we can identify it earlier, prevent it from happening and treat it when we see it.”
Little previous research has been done on diastolic heart failure because there were no animal models — lab mice with the condition — upon which researchers could test new drugs.
Now Alberta HEART– comprised of 24 scientists and clinicians across the research and health care spectrum – has succeeded in creating an animal model with diastolic heart dysfunction.
As well, the Alberta HEART team has examined hundreds of Albertans with heart failure to develop a comprehensive analysis of risk factors, which could be used to build effective strategies to prevent heart failure before it happens.
The team has also succeeded in isolating biomarkers — genetic and biological substances found in the body that uniquely indicate diastolic heart failure — the crucial first step towards creating a simple blood test to make diagnosis easy.
All of this promises to lead to personalized, more effective treatment plans for diastolic heart failure patients, with therapies that take into account the very different cause of their heart failure.
Researchers hope this work will pave the way for human drug trials in the near future.
“The Alberta HEART program will provide advances that will directly benefit those who suffer from this condition but it will also benefit our health care providers,” says Dr. Todd Anderson, co-director of Alberta HEART and director of the Libin Cardiovascular Institute of Alberta.
“A lot of heart failure is looked after by primary care physicians who see this day in and day out. If they better understand the condition, know what to look for, know when to refer and how to treat it better, they will feel much more comfortable looking after these patients. At the end of the day, better health care for patients benefits all of us.”
Partners in this five-year project, now entering its fourth year, include Alberta Health Services (AHS), the University of Alberta, the University of Calgary, the Libin Cardiovascular Institute of Alberta, and the Mazankowski Alberta Heart Institute, with $5 million in funding from Alberta Innovates – Health Solutions.
Steve Blackwell, 52, a participant in the Calgary arm of the Alberta HEART research project, is currently recovering from severe diastolic heart failure. Several months prior to his diagnosis, he began experiencing difficulty sleeping. Doctors determined he had sleep apnea but were unable to pinpoint the underlying cause.
“I knew something was wrong,” Blackwell says. “I felt tired all the time and even the smallest effort could be exhausting.”
Blackwell ultimately wound up in the emergency room and spent six days in hospital, where doctors determined something called viral cardiomyopathy, a condition in which the heart muscle is weakened, led to diastolic heart failure. He also developed an irregular heartbeat and subsequently received an implantable cardioverter-defibrillator, which sends a jolt of electricity to correct any life-threatening, irregular heart rhythms.
“There are days now when I feel fine, but my overall level of energy and stamina isn’t nearly where it used to be,” Blackwell says of his recovery.
February is Heart Month – the Heart and Stroke Foundation’s key opportunity to reach millions of Canadians to alert them to the risks of heart disease and stroke. Heart disease and stroke take a life every seven minutes; 90 per cent of Canadians have at least one risk factor.
Alberta Health Services is the provincial health authority responsible for planning and delivering health supports and services for more than 3.8 million adults and children living in Alberta. Its mission is to provide a patient-focused, quality health system that is accessible and sustainable for all Albertans.
Story by Greg Harris Courtesy of Alberta Health Services
Related Media Coverage
“Diastolic Heart Failure” VIDEO Report by Heather Yourex, Global Calgary