title: Left ventricular systolic performance is improved in elite athletes.
abstract: OBJECTIVE
  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).
  
  
  RESULTS
  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).
  
  
  CONCLUSIONS
  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'.
authors.affiliation: Institute of Sports Medicine and Science, Italian National Olympic Committee, Largo Piero Gabrielli 1, Rome, Italy. stefanocasellimd@gmail.com
authors.forename: Stefano
authors.initials: S
authors.lastname: Caselli
authors.forename: Riccardo
authors.initials: R
authors.lastname: Di Pietro
authors.forename: Fernando M
authors.initials: FM
authors.lastname: Di Paolo
authors.forename: Cataldo
authors.initials: C
authors.lastname: Pisicchio
authors.forename: Barbara
authors.initials: B
authors.lastname: di Giacinto
authors.forename: Emanuele
authors.initials: E
authors.lastname: Guerra
authors.forename: Franco
authors.initials: F
authors.lastname: Culasso
authors.forename: Antonio
authors.initials: A
authors.lastname: Pelliccia
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D016001:Confidence Intervals; D019560:Echocardiography, Three-Dimensional; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D013177:Sports / Q000502:physiology*; D013178:Sports Medicine; D018709:Statistics, Nonparametric; D013318:Stroke Volume / Q000502:physiology*; D013599:Systole; D013997:Time Factors; D016277:Ventricular Function, Left / Q000502:physiology*; D055815:Young Adult