Beta-adrenergic stimulation with dobutamine produced a significantly greater positive inotropic effect on left ventricular contractility than on right ventricular contractility (p<0.0003 for ESPVR).
p-value: p=<0.0003
PURPOSE: The purpose of this study was to compare the response in contractility of the right (RV) and left (LV) ventricle of the heart to beta-adrenergic stimulation using an echo planar MR technique. METHOD: In six sheep, RV and LV pressure-volume (P-V) relationships were constructed simultaneously using intraventricular pressures and volumes measured with echo planar MRI at rest and during dobutamine stress. Contractility changes were quantified by assessment of the end-systolic P-V relationship (ESPVR) and the preload recruitable stroke work (PRSW). RESULTS: Both the ESPVR the the PRSW showed a significant increase in contractility for both ventricles after dobutamine administration. The increase in contractility was significantly larger for the LV than for the RV, both measured wit the ESPVR (p < 0.0003) and the PRSW (p < 0.007). CONCLUSION: This study shows the usefulness of echo planar MRI to assess myocardial contractility of both ventricles simultaneously. Furthermore, the study shows that beta-adrenergic stimulation has a significantly greater positive inotropic effect on LV contractility than on RV contractility.
Jerzewski et al. (Wed,) reported a other. Beta-adrenergic stimulation (dobutamine) vs. Right ventricle response was evaluated on Contractility changes quantified by end-systolic P-V relationship (ESPVR) and preload recruitable stroke work (PRSW) (p=<0.0003). Beta-adrenergic stimulation with dobutamine produced a significantly greater positive inotropic effect on left ventricular contractility than on right ventricular contractility (p<0.0003 for ESPVR).