Heart-lung synchronizations during exercise

Patients diagnosed with heart failure often require the implantation of a pacemaker to improve cardiac function, which in turn, improves exercise tolerance and quality of life. Current pacemaker models work at a fixed time interval for a given heart rate (i.e. 1 second between heart beats at 60 beats per minute). However, the body’s natural homeostatic system creates variations in the time interval in line with one’s breathing cycle (termed respiratory sinus arrhythmia; RSA). A novel pacemaker model has restored RSA when implanted, showing large improvements in cardiac function in animal models of heart failure. While restoration of RSA at rest may improve cardiac function, this synchronization between heart rate and breathing disappears during exercise. Thus, Dr. Stembridge has set out to explore alternative heart-lung synchronization mechanisms in healthy populations during exercise, to guide future pacing principles for novel pacemakers. We will evaluate these mechanisms and their effect on cardiovascular function during exercise in healthy individuals. We hypothesize that cardiorespiratory phase synchronization will remain different across exercise domains in young healthy individuals, and hypo- and hyperventilation will lead to a decrease in left heart output during exercise and exaggerated heart rate response relative to exercise stage.

Faculty Supervisor:

Craig Steinback

Student:

Partner:

Cardiff University

Discipline:

Life Sciences

Sector:

Health and Related Sciences & Technology

University:

University of Alberta

Program: