Left ventricular systolic performance is improved in elite athletes

Abstract

We sought to investigate the systolic time interval (STI) and efficiency of left ventricular (LV) contraction comparatively in elite athletes and healthy sedentary controls by means of three-dimensional echocardiography (3DE). Four hundred and twenty-nine elite athletes, involved in skill (n = 41), power (n = 63), mixed (n = 167), and endurance (n = 158) disciplines and 98 sedentary controls, matched for age, underwent 3DE. By off-line analysis, we measured the absolute and relative (normalized by the R-R interval) timing of LV systolic emptying (STI and STI%) and the systolic flow velocity (SFV = stroke volume/STI). Both STI and STI% were shorter in athletes, regardless of the sport discipline, compared with controls (respectively, 324 ± 36 vs. 345 ± 33 ms, P < 0.001; 30 ± 4 vs. 40 ± 4%; P< 0.001). Regression analysis showed that heart rate was the most important determinant of STI (R(2) = 0.38; P < 0.001), while age, body surface area, blood pressure, LV volumes, and mass had no significant association. After removing the effects of heart rate and gender, athletes showed a significant reduction (by 50.4 ms; 95% confidence interval, from 57.7 to 43.1) in STI compared with untrained subjects. Finally, higher SFV were identified in skill (256 ± 60 mL/s; P < 0.001), strength (297 ± 78 mL/s; P < 0.001), mixed (308 ± 67 mL/s; P < 0.001), and endurance (334 ± 74 mL/s; P < 0.001) athletes compared with controls (204 ± 50 mL/s). Elite athletes show a significant shortening of the systolic time duration in comparison with sedentary controls, in association with a significant increase in LV emptying velocity. This pattern characterizes the physiological LV adaptation of the athletes and may potentially be useful in differential diagnosis of the 'athlete heart'.