Supernormal functional reserve of apical segments in elite soccer players: an ultrasound speckle tracking handgrip stress study.

Background: Ultrasound speckle tracking from grey scale images allows the assessment of regional strain derived from 2D regardless of angle intonation, and it is highly reproducible. The study aimed to evaluate regional left ventricular functional reserve in elite soccer players.
Methods: 50 subjects (25 elite athletes and 25 sedentary controls), aged 26 +/- 3.5, were submitted to an echo exam, at rest and after the Hand Grip (HG) test. Both standard echo parameters and strain were evaluated.
Results: Ejection fraction was similar in athletes and controls both at rest (athletes 58 +/- 2 vs controls 57 +/- 4 p ns) and after HG (athletes 60 +/- 2 vs controls 58 +/- 3 p ns). Basal (septal and anterior) segments showed similar strain values in athletes and controls both at rest (athletes S% -19.9 +/- 4.2; controls S% -18.8 +/- 4.9 p = ns) and after HG (athletes S% -20.99 +/- 2.8; controls S% -19.46 +/- 4.4 p = ns). Medium-apical segments showed similar strain values at rest (athletes S% -17.31 +/- 2.3; controls S% -20.00 +/- 5.3 p = ns), but higher values in athletes after HG (athletes S% -24.47 +/- 2.8; controls S% -20.47 +/- 5.4 p < 0.05)
Conclusion: In athletes with physiological myocardial hypertrophy, a brief isometric effort produces enhancement of the strain in medium-apical left ventricular segments, suggesting the presence of a higher regional function reserve which can be elicited with an inotropic challenge and suitable methods of radial function quantification such as 2D-derived strain.