Efficacy of direct oral anticoagulants vs. warfarin in left ventricular thrombus in myocardial infarction: systematic review and meta-analysis

Abstract

Aims Current recommendations for antithrombotic strategies in left ventricular (LV) thrombus following myocardial infarction (MI) remain uncertain. This study aimed to evaluate the efficacy and safety of direct oral anticoagulants (DOACs) compared to warfarin in LV thrombus following MI. Methods A systematic search using four databases, including PubMed, Embase, Web of Science, and Cochrane CENTRAL, was conducted from inception to 8 July 2024, without language restrictions. The inclusion criteria were studies that included patients with LV thrombus following MI and compared the efficacy or safety of DOACs and warfarin. Results There were 11 studies (3 randomized and 8 nonrandomized) included in this meta-analysis, involving 14 927 participants. We used a random-effects model for this meta-analysis. DOACs were associated with higher thrombus resolution than warfarin, with a risk ratio (RR) of 1.07 [95% confidence interval (CI) 1.00 - 1.15], P U 0.04. Similarly, DOACs were associated with a lower rate of stroke and systemic embolism, with an RR of 0.84 (95% CI 0.78 - 0.90), P < 0.01. DOACs also marginally reduced the rate of major bleeding compared with warfarin, with an RR of 0.87 (95% CI 0.75 - 1.00), P U 0.05. Introduction After the post-PCI era, the survival rate of myocardial infarction (MI) patients has increased. Consequently, concerns about post-MI complications have been rising. A meta-analysis that included 10 076 ST-elevation MI (STEMI) patients reported the incidence of left ventricular (LV) thrombus to be 2.7% and 9.1% after anterior wall STEMI.1 However, due to the limited visualization of LV thrombus by transthoracic echocardiogram (TTE), a study using cardiovascular magnetic resonance (CMR) could improve sensitivity for LV thrombus detection. A meta-analysis of 2072 STEMI patients using CMR reported the incidence of LV thrombus as 6.3% and as high as 19.2% in anterior wall MI patients with LV ejection fraction (LVEF) <50%.2 LV thrombus following MI increased the risk of systemic embolism by 5.45 times compared with non-thrombus.3 A study of 92 MI patients with LV thrombus reported a 16.3% incidence of systemic embolism during a median follow-up of 5.4 years.4 Conclusions DOACs were associated with higher rates of LV thrombus resolution, lower rates of stroke/systemic embolism, and marginally reduced major and bleeding events compared with warfarin in patients with LV thrombus following acute MI. Therefore, DOACs may be a reasonable alternative to warfarin in this setting.