Right ventricular living myocardial slices exhibited a significantly greater relative increase in maximum force amplitude in response to dobutamine compared to left ventricular slices (399% vs 236%).
Do inotropic and vasoactive drugs elicit different biomechanical responses in right versus left ventricular human myocardial slices?
Right ventricular human myocardial slices exhibit stronger baseline contractility and a greater response to dobutamine than left ventricular slices, suggesting the need for ventricle-specific therapeutic approaches.
Absolute Event Rate: 399% vs 236%
p-value: p=0.026
Abstract This study aimed to compare baseline biomechanical contractile properties between right (RV) and left ventricular (LV) human living myocardial slices (LMS) and explore the effect of dobutamine, noradrenaline, adrenaline, levosimendan and enoximone in both ventricles. Sixty-three slices (33 RV, 30 LV) were produced from 5 explanted hearts. At baseline, RV LMS had a higher maximum contraction force, shorter contraction duration, time to peak and time to relaxation, steeper dF/dt and a larger peak area than LV LMS. Dobutamine administration had a larger effect in RV than LV LMS. Spontaneous, irregular contractions were observed after noradrenaline, adrenaline and dobutamine administration. In conclusion, RV LMS showed a stronger contraction with higher contraction velocity as compared to LV LMS and exhibited a greater response to dobutamine. These findings contribute to the understanding of the RV physiology as a separate entity, advocating for a different approach in treating RV or LV dysfunction. Graphical Abstract
Langmuur et al. (Mon,) conducted a other in Heart failure and non-diseased donor hearts (n=5). Dobutamine, noradrenaline, adrenaline, levosimendan, and enoximone vs. Left ventricular slices was evaluated on Relative increase in maximum force amplitude (Fmax) from baseline after dobutamine administration at EC50 (3 µM) (p=0.026). Right ventricular living myocardial slices exhibited a significantly greater relative increase in maximum force amplitude in response to dobutamine compared to left ventricular slices (399% vs 236%).