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 Left atrial appendage occlusion (LAAO) represents an established therapeutic option for stroke prevention in patients with non-valvular atrial fibrillation (AF) and contraindications to long-term oral anticoagulation (OAC). However, the optimal post-procedural antithrombotic regimen remains uncertain, particularly in individuals with a history of major bleeding. Objectives To evaluate the safety and efficacy of a light antithrombotic regimen (single antiplatelet therapy or no therapy) compared with standard therapy (dual antiplatelet therapy or OAC ± antiplatelet) after successful LAAO in patients at very high bleeding risk. Methods We retrospectively analysed 628 consecutive patients from a multicentre registry who completed 12 months of follow-up after percutaneous LAAO. A light antithrombotic regimen was prescribed in 197 patients (31.4%), whereas 431 (68.6%) received a standard regimen. Primary outcomes were death (all-cause and cardiovascular), thromboembolic events (stroke, transient ischaemic attack [TIA], or systemic embolism), and bleeding (any and major, defined by BARC 3–5 criteria). Results: Patients treated with a light regimen had a higher CHA₂DS₂-VASc score (median 4 vs. 3, p<0.001) but a similar HAS-BLED score (median 4). Procedural success was achieved in 99.9% of cases. At 12 months, there were no significant differences between light and standard regimens in terms of all-cause mortality (5.1% vs. 6.7%, p=0.43), ischaemic stroke (1.5% vs. 1.4%, p=0.90), TIA (1.5% vs. 1.3%, p=0.85), or systemic embolism (1.0% vs. 0.7%, p=0.45). Device-related thrombosis (DRT) was infrequent (1.5%) and comparable between groups. Bleeding events were numerically lower in the light regimen group, though not statistically significant (any bleeding 4.1% vs. 6.5%, p=0.43; major bleeding 2.0% vs. 3.5%, p=0.52). Conclusions: In a real-world population of AF patients at very high bleeding risk, a light antithrombotic regimen following LAAO was not associated with increased thromboembolic events or even no antithrombotic therapy in carefully selected patients, although randomised trials are warranted to confirm these observations.