The antithrombotic regimen after left atrial appendage closure LAAC is debated and some patients at very high bleeding risk may also have contraindication to antiplatelet therapy.

We aimed to evaluate the proportion, baseline characteristics and outcomes of patients receiving no antiplatelet therapy (NAPT) after LAAC, compared to patients receiving other antithrombotic regimen (i.e. dual antiplatelet therapy [DAPT], single antiplatelet therapy [SAPT] or oral anticoagulant [OAC])

All consecutive patients with successful LAAC in our institution from November 2013, with available data regarding antithrombotic therapy at discharge were analysed prospectively and retrospectively.

From October 2013 to December 2018, 150 patients (mean age 79.3±7.1 years, 69.3% [n=104] male) underwent successful LAAC. Mean CHA₂DS₂VaSc and HASBLED score was 4.4±1.1 and 3.7±1.2, respectively. At discharge, 14.6% (n=22) of the patients were given NAPT, 47.3% (n=71) were on SAPT, 36.7% (n=55) on DAPT, and only 1 patient had a combination of aspirin and OAC. NAPT patients were not different regarding age (80.8±6.6 vs. 79.0±7.2, P=0.26), gender (65.2% vs. 70.8% male, p=0.65), CHA₂DS₂VaSc score (4.5±1.1 vs. 4.3±1.1, P=0.45) or HASBLED score (3.7±1.1 for both, P=0.99). There were no differences regarding peri-procedural adverse outcomes between NAPT and no-NAPT patients (1 vs. 8 pericardial effusion [P=0.67], 2 vs. 3 major bleeding [P=0.07]) and no in-hospital death. At 3 months follow-up, there was no device-related thrombosis on cardiac CT and overall survival rate was similar in patients receiving NAPT and those receiving SAPT, DAPT or OAC (100% vs. 97.6%, P=0.29).

No antiplatelet therapy after left atrial appendage occlusion appears feasible and as safe as dual or single antiplatelet therapy, with no increase of prosthesis thrombosis or mortality in this population at markedly high bleeding risk.