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Left ventricular function and mechanics in backs and forwards elite rugby union players.

PURPOSE
The aim of the present study was to assess left ventricular (LV) morphological and regional functional adaptations in backs and forwards elite rugby union (RU) players.


METHODS
Thirty-nine elite male RU players and twenty sedentary controls have been examined using resting echocardiography. RU players were divided into two groups, forwards (n = 22) and backs (n = 17). Evaluations included tissue Doppler and 2D speckle tracking analysis to assess LV strains and twisting mechanics.


RESULTS
The elite RU players exhibited a LV remodeling characterized by an increase in LV mass indexed to body surface area (82.2 ± 13.2 vs. 99.9 ± 16.1 and 119.7 ± 13.4 g.m-2, in controls, backs and forwards; P < 0.001). Compared to backs, forwards exhibited lower global longitudinal strain (19.9 ± 2.5 vs. 18.0 ± 1.6%; P < 0.05), lower early diastolic velocity (16.5 ± 1.8 vs. 15.0 ± 2.3 cm.s-1; P < 0.05) and lower diastolic longitudinal strain rate (1.80 ± 0.34 vs. 1.54 ± 0.26 s-1; P < 0.01), especially at the apex. LV twist and untwisting velocities were similar in RU players compared to controls, but with lower apical (-46.2 ± 22.1 vs. -28.2 ± 21.7 deg.s-1; P < 0.01) and higher basal rotational velocities (33.9 ± 20.9 vs. 48.4 ± 20.7 deg.s-1; P < 0.05).


CONCLUSION
RU players exhibited an increase in LV mass which was more pronounced in forwards. In forwards, LV global longitudinal strain was depressed, LV filling pressures were decreased and LV relaxation depressed at the apex.