Assessment of left ventricular systolic function by non-invasive pressure-strain loop area in young male strength athletes

Abstract

Background: The health of athletes has been recognized as a worldwide public concern with more reported sudden cardiac deaths (SCD). Therefore, early detection of abnormal heart function in athletes can help reduce the risk of exercise. A novel valid non-invasive method to evaluate left ventricular (LV) myocardial work (MW) using LV pressure-strain loop (PSL), was used in this paper to explore LV systolic function in young male strength athletes.

Methods: Thirty-six professional young male strength athletes (the athlete group) and 32 healthy, age-matched young men (the control group) were involved in the study. The LVMW parameters were calculated as the area of PSL by two-dimensional speckle tracking echocardiography (2D-STE) and peak systolic LV pressure. The differences between two groups of data and the predictive efficacy of MW parameters for LV systolic function were analyzed.

Results: The athlete group had significantly higher values of global wasted myocardial work (GWW) and peak strain dispersion (PSD) than did the control group (P<0.05). Global myocardial work index (GWI), global constructive myocardial work (GCW) and global longitudinal strain (GLS) were lower in the athlete group than that in the control group, although statistical significance was not reached (P>0.05). Due to the proportion of GWW and GCW, statistically significant reduction was found in global myocardial work efficiency (GWE) in the athlete group. Conventional echocardiography parameters were well correlated with GWW and GWE (P<0.05). The best predictor of LV myocardial contractile performance in the athletes using receiver operating characteristic curve (ROC) was GWE, with the area under ROC (AUC) of 0.733, sensitivity of 83.3% and specificity of 59.4%.

Conclusions: Subclinical changes have appeared in the hearts of young male strength athletes after long-term intensive exercise and LVMW parameters by PSL play an important role in the evaluation of athlete's LV contractile performance.

Keywords: Athlete heart; Echocardiography; Myocardial work; Pressure-strain loop; Two-dimensional speckle tracking.

Fig. 1

a Non-invasive LV PSL diagram of the athlete group. The red loop area represented the average LV global MW index and the green loop area represented MW of basal inferior. b 17-segment bull’s-eye representation of GLS in an athlete. c The MW of global average and basal inferior in an athlete with the green representing constructive work and the blue expressing wasted work. d 17-segment bull’s-eye expression of GWI with areas of normal in green and high in red. MVC, mitral valve closure; AVO, aortic valve open; AVC, aortic valve closure; MVO, mitral valve open

Fig. 2

a and c 17-segment bull’s-eye representation of MW index and myocardial work efficiency from an athlete (GLS 21%, GWI 2335 mmHg%, GCW 2619 mmHg%, GWW 58 mmHg%, GWE 97%). b and d17-segment bull’s-eye diagram of MW index and myocardial work efficiency from the control one (GLS 22%, GWI 2283 mmHg%, GCW 2743 mmHg%, GWW 46 mmHg%, GWE 98%)

Fig. 3

Receiver operating characteristic curve (ROC) for prediction of LV dysfunction in athletes. a GWW. b GWE. GWE was superior to the other parameters to predict LV performance (AUC = 0.733; 95%CI, 0.613–0.853; P<0.05), with the cutoff value of 97.16 mmHg, sensitivity of 83.3%, specificity of 59.4%. GWW was less predictive (AUC = 0.691; 95%CI, 0.562–0.819; P<0.05)