Left ventricular transmural pressure: A predictor of left ventricle unloading in continuous flow left ventricular assist devices

Achieving optimal unloading in patients with left ventricular assist devices (LVADs) is associated with improved outcomes but remains unattainable in some cases. We retrospectively reviewed 33 patients with a HeartMate 3 LVAD who underwent speed optimization with concomitant echocardiography and right heart catheterization for inadequate left ventricular (LV) unloading between January 2016 and December 2023. Patients were stratified based on left ventricular transmural pressure (LVTMP) into two groups: LVTMP ⩽7 mmHg and LVTMP >7 mmHg using a median split approach. Pulmonary capillary wedge pressure (PCWP) decreased in both groups with increased LVAD speed; however, the mean PCWP change per 100 rpm was significantly smaller in patients with LVTMP ⩽7 mmHg (-0.50 vs -0.99 mmHg per 100 rpm, <i>p</i> = 0.003). Comparative analysis demonstrated LVTMP's superiority over established RV markers, with the strongest interaction effect for predicting speed optimization response. Changes in cardiac output were similar between the two groups. In univariate analysis, multiple hemodynamic parameters were significantly associated with reduced LVTMP, including right atrial pressure (OR = 1.27, <i>p</i> = 0.036), TPG (OR = 1.25, <i>p</i> = 0.037), DPG (OR = 1.69, <i>p</i> = 0.012), and PAPi (OR = 0.35, <i>p</i> = 0.019).LVTMP, as a surrogate for true LV preload, particularly in the context of RV failure, may offer predictive value for the success or failure of LV unloading with LVAD speed optimization.