Abstract 16824: Circulating Microvesicles in Heart Failure Patients Prior to, and Following LVAD Implantation

Abstract

Introduction: Elevated levels of circulating endothelial and platelet (EMV and PMV) microvesicles are associated with endothelial dysfunction and thrombosis/inflammation, respectively. EMVs and PMVs are elevated in patients with heart failure with reduced ejection fraction (HFrEF) and are associated with clinical outcomes. We sought to characterize longitudinal changes in EMV and PMV following LVAD implantation in these patients. Methods: Blood samples were obtained from patients with advanced HFrEF (59±9years, N=9 males) during an invasive hemodynamic assessment with Swan-Ganz catheterization 2.7±4.1 and 4.3±1.3 months prior to, and following CF-LVAD implantation, respectively. Circulating concentrations of total MV, EMVs (CD31+) and PMVs (CD42b+) were determined by flow cytometry. Results: Demographics and hemodynamics pre- and post-LVAD implantation are displayed in the table . Prior to LVAD, four patients were on inotropes. Six patients received a Heartware VAD, and four patients received a Heartmate 3 VAD. As demonstrated in the figure , there was a significant reduction in total MV concentration, as well as EMVs and PMVs following LVAD implantation. Conclusion: Circulating concentrations EMVs and PMVs decline significantly in HFrEF patients following LVAD implantation. These findings are indicative of improvements in both endothelial function and thrombotic/inflammatory state associated with the heart-failure syndrome.