Matters of the Heart

13 June 2008

As an exercise physiologist, Bob Haennel has helped pioneer technology that lets heart patients with pacemakers exercise and improve their quality of life. Ask Haennel how he feels about returning to his alma mater and he won't hold back. "I feel very fortunate," he said. "I could be this university's biggest cheerleader." Just what is it that has Haennel so excited? In three words: research, research, research. When former dean Al Cook asked Haennel to leave his position as a professor at the University of Regina and director for the Regina Qu'Appelle Health Region's Cardiac Rehabilitation exercise program to become an "academic leader" in the Faculty of Rehabilitation Medicine, Haennel didn't hesitate. "I thought, 'Do you know what I could do with my research program? I could have a field day!' So I jumped at the opportunity."

In the two years he has been back on campus, Haennel's research wings have spread to include cancer and stroke patients, but "the heart is still number one."
As a leading exercise physiologist in cardiac rehabilitation, Haennel studies the role of physical activity in the management of chronic diseases and has helped pioneer technology that allows heart failure patients with pacemakers to exercise.
But it was by chance that Haennel first became interested in cardiac rehabilitation. As an undergraduate in the 1970s, his exercise physiology course needed volunteers to help with a project looking at how exercise associated with cardiac rehabilitation.
He led participants through drills at the track and then "monitored every movement they made, because at that time no one knew if it was safe or not."
Haennel then did a master's degree in cardiac rehabilitation, focusing on how physical and psychological well-being correlate. Armed with his graduate degree, he took a job in the cardiac rehabilitation program at the Royal Alex Hospital. But at the age of 28, Haennel decided to return to school. Art Quinney, who recently retired as deputy provost of the U of A, was running the campus fitness unit at the time and agreed to take on Haennel as a PhD student. In the early 1980s, Haennel proposed studying something that was unheard of at the time. "In those days, people said that if you had a heart attack, you shouldn't lift anything more than five pounds. Well, I looked at the efficacy of strength training and aerobic exercise and what that did for heart patients. Initially, it met with a bit of resistance from the clinical community because it wasn't the norm."
Haennel soon learned that strength manoeuvres were fine for most people recovering from heart attacks and that they benefit even more when you give them a blended program of weight and aerobic training. "When you do strength training, you don't give them the same volume load and don't put the same pressure on them. At the time we thought, 'Wait a second, maybe we should modify exercise programs to the individual patient's needs.' It makes sense now, but 25 years ago, the thought was just to put them on a bike or a treadmill and improve their aerobic capacity. We now know that tailoring the exercise programs to the patients' abilities and needs is key to long-term adherence."
He earned his PhD from the U of A in 1987 and went on to complete a post-doctoral fellowship in the Division of Cardiology soon after. After a year on a term position in the Faculty of Rehabilitation Medicine, Haennel left for the University of Regina and was soon approached by physicians in that health region to participate in a research program focused on patients with pacemakers. Over the next 15 years he ran a research program that examined the impact of various sensors on the functional ability of pacemaker-dependent patients. At first his worked focused on refining the algorithms of activity sensors and accelerometers, to improve the overall heart rate response of these patients to exertion. "Prior to the introduction of these sensors, pacemakers had fixed heart rates. So no matter what the patient was doing the heart rate did not change," said Haennel.
The sensors were good at generating a quick heart-rate response to movement. The problem was, these non-physiological sensors couldn't match the body's metabolic responses to physical demands. "These early pacemaker sensors had a tendency to generate inappropriate heart rate responses. For example, ascending stairs is metabolically more demanding than descending stairs, but these sensors generated a higher heart rate during the descent," he said. Fortunately, the pacemaker industry was developing a variety of sensors receptive to physiological changes associated with exercise. Haennel's working relationship with pacemaker companies such as Medtronic, Vitatron, Biotronic and St. Jude enabled him to work on the ventilation sensor, the QT sensor and right ventricular impedance sensor. While these devices were superior to the earlier non-physiological sensors in generating an appropriate heart rate and cardiac output response to metabolic demands, they still tended to lag.
"For pacemaker-dependent patients, the physiological sensors were slow to respond, when compared to the responses of a healthy heart."
The next logical step was to combine sensors. The non-physiological sensors provided a rapid initial heart rate while the physiological sensors ensured the overall heart rate response was appropriate for the patient's activity. And by the mid 1990s much of his work was focused on sensor blending.
As pacemakers evolved, so did their applications. By 2000, cardiac resynchronization therapy was being employed in select heart-failure patients. In this therapy, a pacemaker is used to resynchronize the contraction of the ventricles to improve cardiac output and the patient's functional ability. Haennel intended to pursue this area next, but the patient population was not available to him in Regina. So it was fortuitous in early 2004 when he was approached about the position of Chair of the Physical Therapy Department at the U of A.
Haennel had accomplished a lot in Regina. He established a Cardiovascular Research lab in the Regina Qu'Appelle Health Region, served as the associate dean of Kinesiology and Health Studies and expanded the programs and services of the Dr. Paul Schwann Applied Health and Research Centre. "But the opportunity to work in the Faculty of Rehabilitation Medicine at the U of A, combined with the development of the new Mazankowski Alberta Heart Institute was just too attractive, so I applied for the position." When Cook offered him the job, Haennel was ecstatic. "It meant I could pursue my interest in cardiac resynchronization therapy and with the talent and resources available. I felt like I had won the lottery."
His current doctoral student, Corey Tomczak, who came with Haennel from Saskatchewan, is examining the regulation of pulmonary gas exchange dynamics in heart failure in patients receiving cardiac resynchronization therapy. It didn't take much persuading for Tomczak to make the move. "I did my master's degree with Dr. Haennel and we had developed a very good working relationship, so I wanted to continue my work with him," said Tomczak. "He has an established research program in a premier research university. And he always puts the best interest of his students first and provides a research training environment that is commensurate with his students' goals."
Tomczak and Haennel are trying to help increase the patient's functional ability and in turn, improve their quality of life. That's simply what motivates Haennel. It's also the reason you will find him on campus at 6 a.m. every day-and why you might find him still in his lab at 8 p.m. on a Friday night. "My wife laughs at me because I can't stay away. It's been exciting so far and we still have a lot of work to do."
(This article first appeared in Rehab Impact, published by the Faculty of Rehabilitation Medicine.)