Effect of Preload Augmentation on Pulsed Wave and Tissue Doppler Echocardiographic Indices of Diastolic Function After a Marathon

Abstract

The mechanisms underlying alterations in left ventricular diastolic function after a marathon are unknown and may be a consequence of a reduced preload. We sought to assess the effect of preload augmentation through passive leg elevation (PLE) on echocardiographic indices of diastolic function after a marathon. Fourteen trained participants (13 male) were echocardiographically assessed before and after a marathon in the supine position and during PLE. Diastolic function was measured via conventional Doppler, color M-mode, and tissue Doppler echocardiography. Early and late transmitral filling velocities (E and A, respectively), flow propagation velocity of early filling, and basal early and late left ventricular wall velocities (E' and A', respectively) were obtained. The E/A ratio, flow propagation velocity of early filling, and the E'/A' ratio decreased by 31%, 24%, and 32%, respectively (P < .05), after marathon running. Postrace PLE returned E to baseline and increased E/A compared with postrace supine (P < .05). However, E/A remained depressed compared with baseline as a result of the persistent elevation in A. Postrace PLE caused Vp to return to baseline; mean E' also increased (9%, P < .05), but did not return to resting levels. Mean A' was unaffected by postrace PLE, therefore, E'/A' was unchanged postrace despite PLE. Postexercise alterations in Doppler indices of diastolic function can be partially explained by a reduction in preload. However, data from tissue Doppler echocardiography indicate that there is an intrinsic impairment in myocardial relaxation after marathon running.