Safety and efficacy of a light antithrombotic regimen after left atrial appendage occlusion: insights from the LOGIC (Left atrial appendage Occlusion in patients with Gastrointestinal or IntraCranial bleeding) International Multicenter Registry

Background: Antithrombotic therapy (AT) after left atrial appendage occlusion (LAAO) in patients with non-valvular atrial fibrillation (NVAF) has the purpose of preventing device related thrombosis (DRT), avoiding embolic events; nevertheless, the correct antithrombotic regimen after LAAO is still under debate. Aims: Aim of this substudy of the observational LOGIC registry was to describe the efficacy and safety of a light antithrombotic regimen, comprising single antiplatelet therapy or none, compared to a standard antithrombotic regimen, after a successful LAAO. Methods: Patients with NVAF that underwent LAAO were previously included in the LOGIC registry. Patients receiving single or no AT were considered as light therapy group, while other regimen were considered as standard regimen group. Outcomes of interest were death from any causes and cardiovascular death, ischemic stroke, transient ischemic attack and systemic embolization, any bleeding and major bleeding at 12 months. Results: Six hundred and twenty-eight patients were considered in the analysis, 31.4 % received a light antithrombotic regimen. There were no differences in overall and cardiovascular mortality (5.1 % Vs 6.7 %, p = 0.426 and 2.0 % Vs 1.4 %, p = 0.553 respectively). Cerebrovascular stroke and transient ischemic attack were similar between the two groups (1.5 % Vs 1.4 %, p = 0.898 and 1.5 % Vs 1.3 %, p = 0.847). Light regimen was not associated with an increased rate of systemic embolism (1.0 % Vs 0.7 %, p = 0.447 and HR 0.88 [95 % CI: 0.34–2.27; p = 0.79]). A light AT regimen did not affect bleeding events being not different between the two groups (HR 0.71; 95 % CI: 0.33–1.59; p = 0.41). Conclusions: An AT regimen based on single or no antithrombotic therapy after LAAO seems to be safe in patients with high-bleeding risk, without increasing cerebrovascular or peripheral ischemic events.