Comparative Effectiveness of Direct Oral Anticoagulants and Warfarin for the Treatment of Left Ventricular Thrombus

Abstract

Introduction Left ventricular (LV) thrombus is a complication of acute endomyocardial injury and chronic ventricular wall hypokinesis (e.g. dilated cardiomyopathy), resulting in increased risk of thromboembolic complications. Historically, observational studies support the general safety and efficacy of warfarin for this indication. To date, limited data exists regarding the use of the direct oral anticoagulants (DOACs) for LV thrombus. Methods A retrospective cohort study utilizing electronic medical records was conducted from September 2012 - October 2018 at the University of Colorado Hospital System. Patients were included if they had any diagnosis of LV thrombus and received either a DOAC or warfarin within 90 days of diagnosis. The primary outcome was to determine the incidence of thromboembolic stroke in patients receiving a DOAC compared to warfarin. Secondary outcomes consisted of the composite incidence of thromboembolic events (stroke and systemic embolism), bleeding rates defined by the The Global Use of Strategies to Open Occluded Arteries (GUSTO) criteria, and blood product administration. Chi square test was used to analyze categorical variables and the student's t-test and Wilcoxon Rank Sum test for continuous data. All statistical analyses were conducted using SAS. Results A total of 949 patients met inclusion, of whom 180 (19%) received a DOAC and 769 (81%) warfarin. Of the DOAC cohort, 77 (41.6%) received rivaroxaban, 79 (42.7%) apixaban, and 29 (15.7%) dabigatran. For baseline demographic information, see table 1. For the primary endpoint of new onset thromboembolic stroke on or within 90 days of LV thrombus diagnosis, no difference existed between treatment groups (DOAC: 7.8% vs warfarin: 11.7%, p=0.524). When compared to warfarin, no difference existed in the composite of thromboembolic events (33.1% vs 30.6%, P=0.524, respectively) or in GUSTO bleeding (11.1% vs 7.8%, p=0.397, for DOAC vs. warfarin, respectively). However, more patients on warfarin received blood products compared to those taking a DOAC (25.8% vs 13.9%, p Conclusions Compared to warfarin, DOACs may be safe and efficacious for the treatment of LV thrombus, however further studies are warranted.