Preload dependence of color M-mode Doppler flow propagation velocity in controls and in patients with left ventricular dysfunction

The purpose of this study was to assess the effects of preload alterations on color M-mode flow propagation velocity (Vp) in volunteers with normal le ft ventricular (LV) function and in patients with depressed LV function. Co lor M-mode Doppler echocardiography was performed during Valsalva maneuver, passive leg lifting, and after administration of nitroglycerin in 30 healt hy volunteers and in 30 age- and sex-matched patients with previous myocard ial infarction (MI). Mean Vp in controls was 74 +/- 15 cm/s at baseline and 46 +/- 15 cm/s in MI patients (P < .0005). In both groups, minor changes i n Vp were seen during preload alterations; however, these were not signific ant (control P = .72, MI P = .31). In both groups, peak E-wave velocity (P < .0005), ratio of early-to-late peak velocities (P < .0005), and E-wave de celeration time (P < .0005) were found to change during preload alterations . In conclusion, we found that in controls and patients with previous MI, t he color M-mode flow propagation velocity is not affected significantly by preload.