Rivaroxaban versus Vitamin K Antagonists (warfarin) based on the triple therapy for left ventricular thrombus after ST-Elevation myocardial infarction

Background: Left ventricular thrombus (LVT) can complicate ST-Elevation myocardial infarction (STEMI) and is associated with poor outcomes. Conventional triple anticoagulation [Vitamin K Antagonists (VKA) plus dual-antiplatelet therapy (DAPT)] is the first-line therapy for LVT after STEMI. In patients with LVT following STEMI, contemporary data of triple therapy with rivaroxaban are lacking. Methods: We conducted a retrospective cohort study involving 1335 STEMI patients who underwent primary percutaneous coronary intervention (PCI). Among patients who developed LVT after STEMI, we observed differences in efficacy between rivaroxaban plus DAPT therapy and VKA plus DAPT. The time of LVT resolution was also evaluated, as well as net clinical adverse events, and rates of bleeding events. Results: In 1335 patients with STEMI, a total of 77 (5.7%) developed LVT over the follow-up period (median 25.0 months). Of the patients diagnosed with LVT, 31 patients were started on triple therapy with VKA, 33 patients on triple therapy with rivaroxaban. There was a consistent similarity in LVT resolution with rivaroxaban application compared to VKA application during the follow-up period [HR (log-rank test) 1.57(95% CI 0.89–2.77), p = 0.096; Adjusted HR 1.70(95% CI 0.90–3.22), p = 0.104]. Triple therapy with rivaroxaban showed quicker resolution than with VKA (6 months: p = 0.049; 12 months: p = 0.044; 18 months: p = 0.045). Similar risks of ISTH bleeding were not significantly different between the 2 groups [VKA 9.7% vs Rivaroxaban 6.1%, Adjusted HR 0.48 (95% CI 0.73–3.20); p = 0.444)]. Fewer net adverse clinical events (NACE) were observed in the rivaroxaban group [VKA 58.1% vs Rivaroxaban 24.2%; HR (log-rank test) 0.31(95% CI 0.14–0.68), p = 0.003; Adjusted HR 0.23(95% CI 0.09–0.57), p = 0.001]. Conclusion: In the observational study, triple therapy with rivaroxaban has similar and quicker LVT resolution in patients with LVT after STEMI, compared with triple therapy with VKA, and perhaps was associated with a better clinical benefit. Larger sample sizes and randomized controlled trials are needed to confirm this observation.