Outcomes of Impella 5.5/CP use in acute on chronic heart failure: a single center case series

Introduction The mortality rate in acute decompensated heart failure (ADHF) is high, which is a result of a cascade of events leading to multiorgan failure. The prognosis depends on the timing of restoration of cardiac output. Patients not responding to medical management require mechanical circulatory support (MCS) which can assist left ventricular function and prevent organ damage. A microaxial flow pump (mAFP), a short-term MCS, can be used temporarily for stabilizing and bridging patients. We report outcomes of mAFP use in patients with pre-existing chronic heart failure presenting with ADHF. Purpose In this study, we intend to provide a detailed analysis of outcomes associated with the use of a mAFP in patients with ADHF. By evaluating multiple variables collected during treatment, we seek to highlight the efficacy, safety, and potential complications of this device. Materials and Methods This is a retrospective single center study. All patients with a history of pre-existing chronic heart failure, presented with ADHF and managed with mAFP were included. The demographic details, past history, type of mAFP and surgical data of implantation were recorded. Pre- and post-mAFP hemodynamic variables and post-implant complications were also evaluated and compared using appropriate statistical tests. Results We included 56 patients in this study. All patients were managed with either the Impella 5.5/5.0 (n=52, 89.7%) or CP (n=6, 10.3%). After mAFP implantation, there was a significant reduction in vasoactive inotropic score (p<0.001), increase in glomerular filtration rate (p<0.001) and reduction in lactate levels (p<0.001). Two patients (3.4%) were lost to follow-up, 28 patients (51.2%) were bridged to a durable left ventricular assist device (LVAD) and 3 patients (5.2%) to a heart transplant. Eight patients (13.8%) were successfully weaned, defined by more than 30 days survival after mAFP explantation. Seventeen patients (29.3%) died on Impella support. Major complications encountered were bleeding (n=23, 39.7%), any kind of infection (n=37, 63.8%), sepsis (n=9, 15.5%) and renal dysfunction (n=34, 58.6%). Conclusion The use of a mAFP has favorable outcomes in patients with chronic heart failure presenting with ADHF. It has shown significant improvement in hemodynamic parameters post implantation and the majority of patients survived to either destination therapy or successful weaning. More long-term studies are necessary to better delineate the outcomes of mAFP in patients with a history of chronic heart failure.