[Exercise echocardiography and study of the left ventricle in sportsmen during exertion]

The use of an original ultrasonic transducer holder has made possible the recording of M mode and 2D echocardiography during exercise. Left ventricular function was studied during upright bicycle exercise in two groups: 10 trained athletes (Group A) and 10 normal subjects (Group B). All were 20 years of age. Satisfactory echocardiograms were obtained up to a mean heart rate of 180/mn which corresponded to an average work load of 180 W in Group B and 300 W in Group A. The cardiac output was comparable in the two groups up to a 180 W load, but in Group A a lower HR was compensated by a larger stroke volume (SV). The increase in SV in Group A was related to a greater LV end-diastolic dimension (LVEDD) during exercise, whereas the ejection fraction increased less than in the control group. During very strenuous exercise (Group A only) further increases in cardiac output were related mainly to an increased heart rate and to a lesser degree to increased LVEDD and ejection fraction.