THE EFFECTS OF ISOMETRIC STRESS ON LEFT-VENTRICULAR FILLING IN ATHLETES WITH ISOMETRIC OR ISOTONIC TRAINING COMPARED TO HYPERTENSIVE AND NORMAL CONTROLS

Hypertrophy of the left ventricle may be associated with altered left ventricular filling dynamics. To test whether isometric and isotonic t raining affect left ventricular filling differently at rest and during isometric stress, 38 males, 13 long distance runners, eight weight-li fters, eight hypertensive patients and nine age-matched healthy male c ontrols with a mean age of 30 +/- 7 years, were studied before and aft er 90 s of 50% maximal handgrip force. Left ventricular Doppler fillin g parameters were compared in the four groups while they were resting and during isometric stress testing, and the results assessed in relat ion to left ventricular mass index and wall stress. All subjects had n ormal resting filling patterns except for hypertensive patients, and p eak meridional wall stress was low in both athletic groups at rest. We ight-lifters had a hypertensive response during isometric stress testi ng, associated with a reduction in peak E velocity and a marked increa se in peak A velocity, resembling the filling pattern in hypertensive subjects. In runners the filling pattern remained normal. Thus, while the resting left ventricular pattern was normal in all athletes, isome tric stress testing was associated with a hypertensive filling pattern only in weight-lifters compared to normal filling in runners.