Safety of enoxaparin in patients implanted with continuous flow left ventricular assist devices

The objective of this study is to determine the incidence of major bleeding events in patients implanted with continuous flow left ventricular assist devices (CF-LVADs) bridged with enoxaparin (LMWH) compared to intravenous unfractionated heparin (IV UFH) for a subtherapeutic INR on warfarin.

A single-center, retrospective, cohort study was conducted including patients with CF-LVADs implanted between January 1, 2012 and July 1, 2020 who received at least one inpatient dose or outpatient prescription for LMWH or IV UFH at least 60 days after CF-LVAD implantation. The primary endpoint was the incidence of major bleeding.

In total, 176 orders were screened and 90 orders in 62 unique patients were included. Major bleeding and thromboembolic events occurred in 1 (2.5%) versus 4 (10.0%) orders (p = 0.36) and 3 (7.5%) versus 1 (2.5%) orders (p = 0.62) in the LMWH and IV UFH groups, respectively. One patient had a fatal thromboembolic event in each group. More patients receiving IV UFH had minor bleeding events (10 [25.0%] vs. 3 [7.5%]; p = 0.03).

There was no difference between bleeding and thromboembolic events in patients implanted with CF-LVADs prescribed LMWH or IV UFH for bridging of subtherapeutic INRs. Larger prospective randomized data are needed to validate these findings.