Assessing Heart Rate Variability as a Surrogate Measure of Cardiac Autonomic Function in Chronic Traumatic Spinal Cord Injury

Individuals with a spinal cord injury (SCI) are at greater risk of cardiovascular disease (CVD) than able-bodied individuals. A major CVD contributing factor is the presence of autonomic disturbances, but the SCI-related changes in cardiac autonomic function are poorly understood. Heart rate variability (HRV) has been reported to non-invasively assess the cardiac autonomic nervous system (ANS). The following thesis involves investigating resting HRV in 56 subjects with a traumatic chronic SCI with the aim to 1) describe the overall distribution of HRV in SCI; 2) determine whether there are HRV differences based on level and/or severity of injury; and, 3) determine whether there is a relationship between parasympathetic and sympathetic frequency measures. The results revealed that HRV is variable between-subjects, there were no significant HRV differences based on level and/or severity of impairment, and the low frequency-to-high frequency ratio (LF:HF), may not be an applicable measure in traumatic chronic SCI.M.Sc