Tissue Doppler imaging indices of peak systolic velocity significantly increased with dobutamine and decreased with esmolol (P<0.001), correlating strongly with fractional shortening (r=0.88).
Estimación del efecto: r = 0.88 for fractional shortening
valor p: p=<.001
BACKGROUND: Tissue Doppler imaging (TDI) is a novel method of color-coding myocardial velocity on-line. The objective of the present study was to evaluate endocardial velocity with TDI as a method of objectively quantifying alterations in regional contractility over a wide range induced by inotropic modulation. METHODS AND RESULTS: Myocardial length crystals were used to simultaneously assess regional left ventricular (LV) function, and high-fidelity pressure and conductance catheters were used to assess global LV contractility by pressure-volume relations in nine open-chest dogs. Mid-LV M-mode and two-dimensional color TDI images were recorded during control and inotropic modulation stages with dobutamine and esmolol. Predicted significant increases in TDI indices occurred with dobutamine: peak systolic velocity of 4.41 +/- 1.07 to 6.67 +/- 1.07 cm/s*, systolic time-velocity integral (TVI) of 0.43 +/- 0.12 to 0.62 +/- 0.10 cm*, and diastolic TVI of 0.49 +/- 0.11 to 0.71 +/- 0.17 cm*. Opposing significant decreases occurred with esmolol: peak systolic velocity of 4.46 +/- 0.94 to 2.31 +/- 0.81 cm/s*, systolic TVI of 0.47 +/- 0.12 to 0.19 +/- 0.11 cm*, and diastolic TVI of 0.55 +/- 0.11 to 0.33 +/- 0.11 cm* (*all P < .001 versus control). Changes in TDI peak systolic velocity were correlated with changes in fractional shortening (r = .88) and shortening velocity (r = .87) by sonomicrometry. Changes in TDI peak velocity from multiple mid-LV sites also correlated significantly with maximal elastance (r = .85 +/- .04) from pressure-volume relations. CONCLUSIONS: TDI measures reflect directional and incremental alterations in regional and global LV contractility and have the potential to quantify regional LV function.
Gorcsan et al. (Tue,) conducted a other in Alterations in regional left ventricular contractility (n=9). Tissue Doppler imaging (TDI) during inotropic modulation (dobutamine and esmolol) vs. Control stage was evaluated on Changes in TDI indices (peak systolic velocity, systolic TVI, diastolic TVI) and correlation with fractional shortening and maximal elastance (r = 0.88 for fractional shortening, p=<.001). Tissue Doppler imaging indices of peak systolic velocity significantly increased with dobutamine and decreased with esmolol (P<0.001), correlating strongly with fractional shortening (r=0.88).