Hemodynamics of treadmill exercise in normal volunteers
Accurate assessment of ascending aortic blood velocity indices and reproducibility of a Doppler ultrasonic system during exercise were determined; the Doppler technique was then used to assess the effects of age, sex, and beta-blockade on exercise hemodynamics. Doppler-determined velocity correlated well with an invasive electromagnetic system. Reproducibility of Doppler variables during three exercise tests was high (coefficient of variation less than 10%) and did not deteriorate appreciably with exercise. Peak velocity (PV) and maximum acceleration (MA) was inversely related to age, the relationship is more significant during exercise, whereas the systolic velocity integral showed no such relationship either at rest or during exercise. Doppler variables showed no difference between sexes, except at high levels of exercise. Beta blockade markedly attenuated the exercise response as shown by significant decreases in both MA and PV during exercise. The Doppler velocity data presented in this study provide a reference against which previously documented changes in exercising ischemic patients can be better related.
Chandrashekhar YS, Bali HK, Anand IS, Malhotra RM et al. Hemodynamics of treadmill exercise in normal volunteers. Ind Heart J (DP Basu Award, 1989).