Outcomes of Systemic Anticoagulation with Bivalirudin for Impella 5.0

Abstract

<h3>Purpose</h3> The Impella 5.0 (IMP5) is a surgically implanted axial flow pump used in cardiogenic shock. Anticoagulation (AC) strategy with unfractionated heparin (UFH) is used for pump patency. Alternative AC strategies have not been well defined. This study examines the outcomes of patients treated with bivalirudin (BIV) for AC during IMP5 utilization. <h3>Methods</h3> This single center, retrospective study included patients supported on IMP5 with BIV based AC. The primary end points were recovery, bridge to left ventricular assist device (LVAD), cardiac transplant (HTX), or death. Secondary end points included clinically significant bleeding (TIMI major or minor), incidence of tPA (Tissue Plasminogen Activator) use for suspected pump thrombosis, stroke, and device outcomes. <h3>Results</h3> 31 patients were included with a mean age of 57.4 years and 19.4% female. 26 patients (84%) received BIV purge solution. The median duration of IMP5 was 6 days. Most patients (38.7%) were bridged to LVAD; 16.1% were bridged to HTX, 16.1% recovered, and 29% died. 1 patient (3.2%) suffered ischemic stroke and 12 patients (38.7%) developed TIMI major or minor bleeding. . tPA was administered to 8/31 (25.8%) of patients. There was no difference in time to therapeutic AC between patients given or not given tPA(p=0.18). Of those given tPA, 37.5% had therapeutic aPTTs (61-75 seconds) immediately prior to tPA. 17/23 (73.9%) of patients not given tPA had therapeutic aPTTs (Fig. 1). Overall time to therapeutic range for all subjects is displayed in Figure 2. Logistic regression analysis demonstrated that duration of IMP5 was a significant predictor of tPA use (OR 1.28; 1.04-1.56). There were no cases of pump failure. <h3>Conclusion</h3> Use of BIV as an alternative to UFH for IMP5 was proven to be feasible with most patients surviving to recovery, LVAD, or HTX.