Abstract
This longitudinal observational study aimed to determine if ventricular dimensions of the athlete's heart remain balanced and proportional to peak oxygen uptake (VO(2)peak) following long-term deconditioning in elite athletes. Fourteen mixed-type male athletes (7 soccer, 7 handball players) were prospectively evaluated with cardiac magnetic resonance imaging and cardiopulmonary exercise testing while active at elite level and after retirement. Athletes were cross-sectionally compared to 14 age-matched controls at baseline and follow-up. Statistical analysis was performed using nonparametric tests. Descriptive statistics are presented as median [Q1, Q3]. Since baseline, athletes reported continued elite sports for 5 [2, 9] years followed by retirement for 12 [7, 14] years. Left ventricular end-diastolic volume (LVEDV) decreased by 17% (261 mL to 222 mL, p < 0.001). Right ventricular end-diastolic volume (RVEDV) decreased by 14% (266 mL to 232 mL, p < 0.001). Left atrial end-systolic volume decreased by 16% (94 mL to 82 mL, p < 0.05). Peak oxygen uptake (VO(2)peak) decreased by 17% (3.96 L/min to 3.37 L/min, p < 0.001). There were no differences between athletes after retirement compared to controls. LVEDV and RVEDV were balanced in athletes at baseline (r(s) = 0.92, p < 0.001) and follow-up (r(s) = 0.92, p < 0.001). LVEDV and RVEDV indexed to VO(2)peak remained unchanged after deconditioning. Exercise-induced cardiac remodeling was reversible after long-term deconditioning in this cohort of elite athletes. LVEDV and RVEDV decreased and remained balanced and proportional to VO(2)peak. This study indicates that cardiac adaptations to sports are physiological. However, more research is needed to investigate the reversibility of exercise-induced cardiac remodeling in disciplines with higher demands on endurance performance.