Reverse Myocardial Remodeling with Centrifugal versus Axial-Flow Left Ventricular Assist Device in Chronic Heart Failure Patients

Abstract

Recent studies have shown enhanced survival and reduced morbidity with centrifugal (HeartMate 3-HM3) left ventricular assist device (LVAD) compared with axial-flow (HeartMate II-HMII) LVAD. However, differences in LVAD-induced left ventricular (LV) reverse remodeling between the two devices remain uninvestigated. The aim of our study was to compare the LV structural and functional changes between these two types of mechanical unloading. Echocardiographic parameters of LV structure and function were obtained pre-implant and at 1, 3, 6, and 12 month of LVAD support. Statistical comparison of quantitative data was performed using 2-tailed Wilcoxon signed-rank test for paired samples and categorical data were compared using Fisher's exact test. A total of 32 consecutive patients (median age 62.5 [IQR 52-68] years, 15.6% female) received axial-flow LVAD (HMII) and 31 consecutive patients (median age 58 [IQR 47-71] years, 16.1% female) received centrifugal LVADs (HM3). There were no significant differences in the baseline characteristics between the study groups. Following LVAD support there were no differences in the LV ejection fraction or LV mass index between the two types of mechanical unloading across all time points (figure 1A and 1B). In centrifugal LVAD patients, LV end diastolic volume index was lower at 1 and 3 months and LV end systolic volume index was lower at 1 month. No differences were identified after 3 months of mechanical unloading (figure 1C and 1D). Both centrifugal and axial-flow LVADs resulted in improved LV function and structure. Although LV volumes were found to be lower at 1 and 3 months in centrifugal pump patients, long-term (> 3month) mechanical unloading seem to exert similar effects on LV structural and functional parameters.