Evidence for Chronotropic Incompetence in Well-healed Burn Survivors

• Published in: Journal of burn care & research Vol. 44; no. 2; p. 431
• Main Authors: Foster, Josh, Watso, Joseph, Crandall, Craig G
• Format: Journal Article
• Language: English
• Published: England 02.03.2023
• Subjects: Adult; Body Surface Area; Burns; Exercise; Exercise Test; Heart Rate - physiology; Humans; Oxygen Consumption - physiology; Survivors
• ISSN: 1559-0488
• DOI: 10.1093/jbcr/irac056

Due to various pathophysiological responses associated with a severe burn injury, we hypothesized that burn survivors exhibit chronotropic incompetence. To test this hypothesis, a graded peak oxygen consumption (V̇O2peak) test was performed in 94 adults (34 nonburned, 31 burn survivors with 14-35% body surface area grafted, and 29 burn survivors with >35% body surface area grafted). The threshold of 35% body surface area grafted was determined by receiver operating characteristic (ROC) curve analysis. Peak exercise heart rates (HRmax) were compared against age-predicted HRmax within each group. The proportion of individuals not meeting their age-predicted HRmax (within 5 b/min) were compared between groups. Age-predicted HRmax was not different from measured HRmax in the nonburned and moderate burn groups (P = .09 and .22, respectively). However, measured HRmax was 10 ± 6 b/min lower than the age-predicted HRmax in those with a large burn injury (P < .001). While 56 and 65% of individuals in the nonburned and moderate burn group achieved a measured HRmax within 5 b/min or greater of age-predicted HRmax, only 21% of those in the large burn group met this criterion (P < .001). These data provide preliminary evidence of chronotropic incompetence in individuals with severe burn injury covering >35% body surface area.