Safety of Once Daily Enoxaparin for Anticoagulation Bridging in Patients with HeartMate III Left Ventricular Assisted Device

Abstract

<h3>Purpose</h3> Most centers bridge patients with Left Ventricular Assist Device (LVAD) patients with heparin drip to avoid thromboembolic complications based on data from HeartMate II. Because of improved hemocompatibility of third generation HeartMate III (HM3), Low molecule weight heparin like enoxaparin has been used to bridge to warfarin when the INR (International Normalized Ratio) is subtherapeutic. Once daily dosing has been used in select patients with higher bleeding risk. However, data supporting this approach is limited. We investigate the safety of using once daily Enoxaparin dosing to bridge subtherapeutic warfarin in patients on HMIII LVAD. <h3>Methods</h3> We conducted a retrospective review of patients who underwent HMIII LVAD implantation from 2018 to 2020. We identified 22 patients who received enoxaparin daily bridging after LVAD implantation. We investigated complications related to enoxaparin use and the necessary data parameters to determine the safety profile of once daily enoxaparin use. The primary outcome was in-pump thrombosis. Secondary outcomes included ischemic stroke, embolic phenomenon, acute kidney injury and bleeding events. <h3>Results</h3> 52 patients were screened, 22 patients of which bridged at least once with enoxaparin. 10 patients received multiple rounds of enoxaparin bridging over their course of follow up. The average enoxaparin course was 3-7 days and extended only if INR remains below 1.6. Enoxaparin was held once the INR reaches 1.8. There were no incidence of pump thrombosis, ischemic stroke or embolic phenomenon related to enoxaparin bridging. No significant events were noted in terms of worsening thrombocytopenia, anemia, renal function, bleeding events, or rates of infection. <h3>Conclusion</h3> Once daily enoxaparin dosing as a bridge to subtherapeutic anticoagulation with warfarin for HM III patients is a safe and effective method for preventing pump thrombosis while significantly reducing the need for hospital admissions for heparin bridging.