Mechanical Circulatory Support (MCS) Patients Bridged with Enoxaparin in the Outpatient Setting: Cedars-Sinai Medical Center Experience

Abstract

MCS is a therapeutic option for end-stage heart failure patients. Due to inherent thrombotic risk associated with current MCS, success hinges on appropriate anticoagulation. Currently, unfractionated heparin (UFH) is used to bridge MCS patients with subtherapeutic INR in an inpatient setting, with limited outpatient experience. This study aims to assess the safety of bridging outpatient MCS patients with enoxaparin. Medical records from 6/2015-7/2019 were retrospectively reviewed with IRB approval. Patients bridged with enoxaparin were screened and compared with non-bridged patients. The primary endpoint was the occurrence of major bleeding or thrombosis events within the first 30 days of enoxaparin initiation. The secondary endpoint included freedom from events after the first 30 days of enoxaparin initiation and patient survivability until the last follow-up. The economic impact was also evaluated. Kaplan-Meier method and Log-rank statistical tests were used to compare groups. 62 MCS patients met the inclusion criteria and were bridged with enoxaparin and 117 bridging episodes were analyzed. 7 patients experienced 8 major bleeding events and 2 major thrombotic events during the first 30 days of enoxaparin bridge. 3-year survival was 78.1% in the enoxaparin bridged group compared to 55.0% in the non-bridged patients (p-value 0.001). In patients with no events, 3-year survival was 80.7% for enoxaparin bridged patients compared to 76.7% in non-bridged patients (p-value 0.001). In the patients with bleeding events, 3-year survival was 55.6% in enoxaparin bridged patients compared to 45.8% in non-bridged patients (p-value 0.001). At 1 year, freedom from bleeding in the enoxaparin bridged patients was 72.6% in those with no events within the 30 days of bridging compared with 0% in those with an event within the 30 days of bridging (p-value 0.001). The use of enoxaparin bridging was associated with improved 3-year survival, even in patients with bleeding event within 30 days after initiation. Freedom from bleeding within the first 30 days after enoxaparin bridge was associated with a higher freedom from bleeding at one year. Enoxaparin bridging appears to be safe in MCS patients. The economic impact will be presented in the final report.