Objectives To investigate the heart sound signals in elite male athletes so as to provide baseline data as a references for cardiac contractility and function.
Methods Forty-four subjects from the physical education department in Beijing Sport University (National Second Grade Athletes or above) were enrolled and evaluated. The heart sound signals of athletes were examined by Exercise Cardiac Contractility Monitor (ECCM) in a quiet state. This study included three indexes: HR, S1/S2 and D/S. S1/S2 refer to amplitude ratio of the first to second heart sound, D/S refer to ratio of diastolic to systolic duration. The first heart sound (S1) is a direct manifestation of the left ventricular contractile state, D/S is used to evaluate whether the myocardial perfusion time is sufficient. The two indexes usually were known as the most practical indicators from cardiac acoustics.
Results The heart rate was 70.5 ± 8.5 beats/min, S1/S2 was 2.8 ± 1.7 and D/S was 1.9 ± 0.4. In a quiet state (inactivity), S1/S2 value is below 4 in health people. The value of D/S≥1.5 is considered as a good value in people. D/S≥1.5 of 41 subjects in this study show that 93.2% elite athlete’s myocardial perfusion time is sufficient and they reach a very good condition in heart function.
Conclusions The heart sound signals, such as S1/S2 and D/S, are able to reflect the functional status of athletes. These observations are beneficial to evaluation of cardiac function in elite athletes. However, the further expanded studies are expected.