Isoproterenol Improves Hemodynamics And Right Ventricle-Pulmonary Artery Coupling After Heart Transplantation.

BACKGROUND

Right ventricular failure (RVF) is a major cause of early mortality after heart transplantation (HT). Isoproterenol has chronotropic, inotropic, and vasodilatory properties which might improve right ventricle function in this setting. We aimed to investigate the hemodynamic effects of isoproterenol on patients with post-HT RVF.

METHODS

We conducted a one-year retrospective observational study including patients receiving isoproterenol and dobutamine for early RVF after HT. A comprehensive multiparametric hemodynamic evaluation was performed successively at three times: no isoproterenol, low doses: 0.025 µg/kg/min and high doses: 0.05 µg/kg/min (henceforth respectively called no-iso, low-iso and high-iso).

RESULTS

From June 2022 to June 2023, 25 patients, median [IQR25-75] age 54 [38-61] years, were included. Before isoproterenol introduction, all patients received dobutamine and 15 (60%) were on veno-arterial extracorporeal membrane oxygenation. Isoproterenol significantly increased heart rate from 84 [77-99] (no-iso) to 91 [88-106] (low-iso) and 102 [90-122] bpm (high-iso, p<0.001). Similarly, cardiac index raised from 2.3 [1.4-3.1] to 2.7 [1.8-3.4] and 3 [1.9-3.7] l/min/m

CONCLUSIONS

In post-HT RVF, isoproterenol exhibits chronotropic and inotropic effects, thereby improving RV-PA coupling and resulting in a clinically relevant increase in the cardiac index.