Cardiac remodeling in well-healed burn survivors after 6 months of unsupervised progressive exercise training.

ABSTRACT

Aerobic exercise is important in the rehabilitation of individuals with prior burn injuries, but no studies have examined whether adult burn survivors demonstrate cardiac remodeling to long-term aerobic exercise training. In this study, we tested the hypothesis that 6 months of progressive exercise training improves cardiac magnetic resonance imaging-based measures of cardiac structure and function in well-healed burn survivors. Secondary analyses explored relations between burn surface area and changes in cardiac structure in the cohort of burn survivors. V̇o2peak assessments and cardiac magnetic resonance imaging were performed at baseline and following 6 months of progressive exercise training from 19 well-healed burn survivors and 10 nonburned control participants. V̇o2peak increased following 6 months of training in both groups (Control Δ5.5 ± 5.8 mL/kg/min; Burn Survivors Δ3.2 ± 3.6 mL/kg/min, main effect of training, P < 0.001). Left ventricle (LV) mass (Control Δ1.7 ± 3.1 g/m2; Burn survivors Δ1.8 ± 2.7 g/m2), stroke volume (Control Δ5.8 ± 5.2 mL/m2; Burn Survivors Δ2.8 ± 4.2 mL/m2), and ejection fraction (Control Δ2.4 ± 4.0%; Burn Survivors Δ2.2 ± 4.3%) similarly increased following 6 months of exercise training in both cohorts (main effect of training P < 0.05 for all indexes). LV end-diastolic volume increased in the control group (Δ6.5 ± 4.5 mL/m2) but not in the cohort of burn survivors (Δ1.9 ± 2.7 mL/m2, interaction, P = 0.040). Multiple linear regression analyses revealed that burn surface area had little to no effect on changes in ventricular mass or end-diastolic volumes in response to exercise training. Our findings provide initial evidence of physiological cardiac remodeling, which is not impacted by burn size, in response to exercise training in individuals with well-healed burn injuries.NEW & NOTEWORTHY Aerobic exercise is important in the rehabilitation of individuals with prior burn injuries, but no studies have examined whether adult burn survivors demonstrate cardiac remodeling to long-term aerobic exercise training. In this study, we tested the hypothesis that 6 months of progressive exercise training would improve cardiac magnetic resonance imaging-based measures of cardiac structure and function in well-healed burn survivors. Our findings highlight the ability of exercise training to modify cardiac structure and function in well-healed burn survivors and nonburned sedentary controls alike.