Direct oral anticoagulants compared to vitamin K antagonist for the management of left ventricular thrombus

Abstract

Aims: Left ventricular (LV) thrombus is increasingly detected in patients with and without ischaemic heart disease due to the increased availability of cardiac magnetic resonance imaging. Risk factors include anterior ST elevation myocardial infarction, delayed reperfusion therapy, and non-ischaemic cardiomyopathy with severe LV systolic dysfunction. We aimed to report the characteristics and outcomes of patients with LV thrombus treated with either vitamin K antagonist (VKA) or direct oral anticoagulants (DOAC) with a view to describing differences in efficacy, specifically, subsequent thromboembolic events, thrombus resolution, and also side effects of therapy including clinically significant bleeding. Methods and results: We conducted a retrospective, observational cohort study of patients diagnosed with LV thrombus between 1 December 2012 and 30 June 2018 and treated with either DOAC or VKA. We recorded patient demographics, past medical history, prescribed medications, and baseline investigations. The primary outcomes were rates of thromboembolism and clinically significant bleeding, with secondary outcomes of thrombus resolution on repeat cardiac imaging, repeat hospitalization, and all-cause mortality. During the study period, 84 patients were diagnosed with and managed for LV thrombus. Of these, 62 received VKA and 22 DOAC including 13 prescribed rivaroxaban, eight apixaban, and one dabigatran. Most patients 75 (89%) were male with an average age of 62 ± 14 years. Ischaemic heart disease was the cause of LV impairment in 73 (87%) patients. Baseline characteristics were similar between groups at baseline. Most n = 55 (65%) were co-prescribed a single antiplatelet agent and 32 (38%) received dual-antiplatelet therapy. During an average follow-up of 3.0 ± 1.4 years, there were no statistically significant differences between VKA and DOAC in rates of stroke (2% vs. 0%, P = 0.55), other thromboemboli (2% vs. 0%, P = 0.55), or clinically significant bleeding (10% vs. 0%, P = 0.13). The average interval to cardiac imaging follow-up was 233 ± 251 days and was not different between groups (P = 0.83), and there was no difference in the rate of resolution of thrombus (76% vs. 65% P = 0.33). Rehospitalization (50% vs. 45%: P = 0.53) and all-cause mortality (10% vs. 14%; P = 0.61) were also similar. Conclusions: Our data suggest that DOACs are likely to be at least as effective and safe as VKA for stroke prevention in patients with LV thrombus and, despite their lack of a licence for this indication, are therefore likely to represent a reasonable and more convenient option for this setting. The optimal timing and type of anticoagulation for LV thrombus, as well as the role of screening for high-risk patients, should be tested in prospective, randomized trials.