Geert Kleinnibbelink

Cardiac Remodelling in Olympic Athletes 4 91 INTRODUCTION Exercise training represents a potent stimulus for remodelling of the heart. Recent prospective and long-term intervention studies support the presence of predominant eccentric ventricular adaptation in response to exercise training. 1, 2 In other words, regular exercise training leads to a balanced increase in both volume and mass, whilst function seems largely preserved. 1 Previous work largely focused on either adaptation of the left side or adaptation of the right side of the heart in response to exercise training. As such, there is an important gap in the literature pertaining to the lack of knowledge whether exercise training differentially affects the left versus right ventricle in elite athletes. Both ventricles receive a similar amount of blood. Due to their distinct geometry andmass, with the right ventricle (RV) being larger in volume but smaller in wall thickness than the left ventricle (LV), both ventricles may be exposed to distinct hemodynamic stimuli, potentially leading to different patterns of adaptation in both structure and function. 3 Indeed, exercise leads to distinctly different changes in afterload for both ventricles, with relatively larger increases in afterload for the RV. 4 This supports the potential for different adaptation between ventricles. Better insight into differences in remodelling between ventricles is highly relevant, especially since previous studies have linked exercise- induced RV cardiomyopathy to high volumes of exercise training in elite athletes. 5, 6 Insight into the potential presence of side-specific physiological remodelling of the heart will also contribute to improved interpretation of pre-participation screening for high-risk cardiovascular conditions associated with sudden cardiac arrest in athletes. The aim of this study, therefore, was to examine the impact of an increase in volume (across 9-months) in elite rowers on left- and right-sided cardiac structure, function and mechanics (i.e. longitudinal, radial and circumferential strain, twist and strain-volume/ area loops). Based on the higher relative workload for the RV 4 , we expect larger structural cardiac adaptation in the RV (whilst preserving function) compared to the LV in elite rowers. Previous work suggested that sex may differently affect cardiovascular function during physiological stimuli. 7, 8 Based on cross-sectional comparisons, similar patterns of cardiac remodelling have been observed with static and mixed exercise between men and