Chronic adaptation of atrial structure and function in elite male athletes

The aim of this study was to establish the degree of structural and functional adaptations in the left (LA) and right atria (RA) in elite male athletes engaged in 'high dynamic : high static' (HDHS) and 'low dynamic : high static' (LDHS) sporting disciplines compared with sedentary controls.

Eighteen male, elite HDHS athletes (13 boxers and 7 triathletes), 18 male, elite LDHS athletes (8 weightlifters and 10 Akido), and 20 male, age-matched sedentary controls were assessed using conventional 2D and myocardial speckle tracking (MST) echocardiography. Absolute LA and RA volumes [end systole (VOLes), pre A (VOLpreA), and end diastole (VOLed)] as well as the functional indices of reservoir (RESvol), conduit (CONvol), and booster volumes (BOOvol) were defined. MST allowed the assessment of atrial strain (ε) during the reservoir (RESε), conduit (CONε), and booster (BOOε) phases of the cardiac cycle. Both LA and RA sizes were significantly larger in HDHS compared with LDHS and controls (P < 0.05) across all structural and functional volume parameters with no significant difference between LDHS and controls (LAVOLes 35 ± 8, 26 ± 10, and 23 ± 5 mL/m(2); RAVOLes 37 ± 10, 26 ± 9, and 23 ± 5 mL/m(2), LARESvol 35 ± 9, 25 ± 11, and 23 ± 7 mL; RARESvol 41 ± 11, 34 ± 11, and 28 ± 7 mL for HDHS, LDHS, and controls, respectively). RA : LA ratios were >1 in all groups due to a comparatively larger RA volume (RAVOLes : LAVOLes 1.05 ± 0.26, 1.12 ± 0.55, and 1.04 ± 0.28 for HDHS, LDHS, and controls, respectively, P > 0.05). There was no significant between group differences for any ε parameter.

Bi-atrial hypertrophy is demonstrated in HDHS athletes and not in LDHS athletes, suggesting that the dynamic component to training is the primary driver for both LA and RA adaptation. Although functional data derived from volume shifts suggest augmented function in HDHS athletes, MST imaging demonstrated no difference in intrinsic atrial ε in any of the groups.