Non-invasive measurement of the response of right ventricular pressure to exercise, and its relation to aerobic capacity

Abstract

Exercise echocardiography assesses exercise-induced pulmonary hypertension. The upper normal limit of right ventricular systolic pressure during exercise is not well established. Our study aims to investigate the response of right ventricular systolic pressure in relation to aerobic capacity. Cardiopulmonary exercise testing using a treadmill, and echocardiography during supine cycling, were performed in 113 healthy volunteers aged 13 to 25 years. Maximal right ventricular systolic pressure during evaluable exercise studies obtained in 108 subjects showed a Gaussian distribution only after separating the endurance trained subjects, specifically 12 athletes with Z-score of peak oxygen uptake higher than 2.0, from the normally trained group of 97 subjects. Maximal right ventricular systolic pressure during exercise in the normally trained group showed a mean of 38.0 millimetres of mercury, with standard deviation of 7.2, a median value of 39.0, and a range from 17 to 63, and the 95th percentile was 51 millimetres of mercury. In the athletes, the maximal right ventricular systolic pressure was higher, with a median of 55.5, a range from 28 to 69, this being significant, with p equal to 0.004). Of the 12 athletes, 8 (67%) showed a response of right ventricular systolic pressure to exercise exceeding 50 millimetres of mercury, but only 8 of 97 normally trained subjects (8%) showed a similar response, this also being significant, with p less than 0.001. Our study confirms the great variability in the response of right ventricular systolic pressure to exercise in healthy individuals, with 50 millimetres of mercury representing the upper normal limit. Endurance-trained athletes show higher levels, and two-thirds have abnormal responses exceeding 50 millimetres of mercury.