Abstract 17790: Can 3D Echocardiography Play a Role in Left Ventricular Assist Device Optimization?

Introduction: Left ventricular (LV) assist device (LVAD) has emerged as a valuable option for patients with severe congestive heart failure both as bridge to transplantation or destination therapy. Speed optimization of LVAD is currently based on the position of the inter-ventricular septum, mitral regurgitation severity and aortic valve opening. Hypothesis: We hypothesized that 3D transthoracic echocardiography (3DE) would provide additional information on left and right ventricular (RV) volumes and shape, which could be valuable in determining optimal LVAD speed. Our aim was to assess the feasibility of combined 3D LV and RV analysis during an incremental RAMP study. Methods: Six consecutive patients undergoing a RAMP test were studied. Device speed was increased from 8000 to 12000 rpm in 400-rpm increments for axial-flow pumps (n=2) and from 2300 to 3200 rpm in 100 rpm increments for centrifugal-flow pumps (n=4). Transthoracic 3DE apical full-volume datasets of the LV and the RV were acquired (Philips) at every other step. RV and LV endocardial surfaces were reconstructed using commercial software (TomTec) and used to calculate ventricular volumes. Custom software was used to calculate LV shape indices of sphericity and conicity (a perfectly spherical/conical ventricle would result in 1.0 value). Results: Data acquisition and post-processing was feasible in 5/6 patients. In axial pumps (Figure), increments in LVAD speed were associated with gradually decreasing LV volume, while RV volume initially decreased to a minimum and then increased at higher speeds. These volumetric changes were associated with alterations in LV shape, with the LV becoming less spherical and more conical at higher speeds. With centrifugal pumps, increased speed was associated with similar changes in LV shape but with minimal changes in volumes. Conclusions: Acquisition of 3D datasets during RAMP studies is feasible and could become a valuable aid in optimizing LVAD pump speed.