Impact of left ventricular ejection fraction on left ventricular thrombus resolution

Poor left ventricular ejection fraction (LVEF) is associated with an increased risk of left ventricular (LV) thrombus formation. However, the effect of LVEF on thrombus resolution remains unclear. We prospectively enrolled patients from 2020 to 2022 and retrospectively from 2010 to 2020 at the National Center for Cardiovascular Diseases, China. Patients with LV thrombus diagnosed within the last 3 months were included. The primary outcome was the resolution of LV thrombus at 12 weeks. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox regression, adjusting for potential covariates. A total of 380 patients on oral anticoagulation for ≥ 12 weeks were included, with a median age of 50.8 years (81.6% male). Dilated cardiomyopathy was the most common underlying condition (51.6%). Direct oral anticoagulants (DOACs) were prescribed to 53.7% of patients. The median baseline LVEF was 30%. In unadjusted analysis, thrombus resolution was higher in patients with LVEF ≤ 30% (78.5% vs. 63.9%, HR 0.61, 95%CI 0.48–0.78, P < 0.001). However, after adjustment for confounders, the difference was not significant (HR 0.79, 95%CI 0.61–1.03, P = 0.089). In multivariable analysis, DOAC use was associated with a higher likelihood of thrombus resolution compared to warfarin (HR 1.34, 95% CI 1.04–1.74, P = 0.024). Baseline LVEF was not a significant predictor of LV thrombus resolution after adjustment. DOACs were more effective than warfarin in promoting thrombus resolution, warranting further investigation. This study was a combined cohort from two studies (ClinicalTrials.gov: NCT04970381, NCT 05006677).