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Introduction Patients are recommended a short course of oral anticoagulation (OAC) or dual antiplatelet therapy (APT), followed by long term single APT post left atrial appendage occlusion (LAAO), leading to criticism that LAAO has not been robustly tested as an anti-stroke strategy. In the NHS, most LAAO is performed in high-risk patients who cannot safety take OAC in the long term, and for whom single APT may still confer a significant bleeding risk. In our centre we decided to halt any OAC/APT between 6-12 weeks post implant and review the outcomes.Methods Retrospective follow up of consecutive LAAO patients between 2015-2022.Results 59 patients were implanted with a Watchman LAAO device, mean age 76.8. Mean CHADSVASc = 3.7, HASBLED 3.3.29/59 (49.1%) had previously suffered an intra-cranial haemorrhage (ICH).A total of 288 patient-years were emboli-free, and 309 years of total survival post procedure. 17 patients died during this follow up period – 4 cancer, 3 ICH, 3 fatal ischaemic strokes, 7 other causes. All bleeding fatalities were off OAC/APT.5 ischaemic strokes and 1 TIA occurred in 6/59 (10.1% between 2015 and 2021), giving a 3-yr event rate of 4.1%, and 7.4% at 5 yrs – substantially lower than predicted by CHADSVASc. All strokes occurred >1 yr post implant, with the TIA occurring in the first 4 weeks post implant.Only 6 patients did not survive less than 6 years (11%).Post procedure 54/59 had DAPT for 12 weeks, 4 had half dose DOAC and 1 haemophiliac had 50 days of tinzaparin, after which all patients came off all OAC/APT.42 underwent post implant TOE, with only 1 transient device-related thrombus observed, and with no embolic events; another single patient was found to have device leak, but with not clinical sequelae noted over the subsequent 4 years (alive to date).Discussion Despite manufacturer’s advice to continue SAPT for life, many centres aim to stop this between 6-12 months. 1 A large registry has shown a significant risk in the first 6 months (3.8-5.0%),2 and whilst other data suggests 7-14% suffer bleeding in the first 0-90 days.3 4Stopping at 12 weeks may be ahead of anticipated device endothelialisation, but clinically only 1 patient had an embolic event (TIA) during this time in our series, and we feel the strategy is safe enough to merit formal testing in a multi-centre trial.References Boersma LV, et al. EWOLUTION study. Circ Arrhythm Electrophysiol. 2019 Apr;12(4).Freeman JV, et al. Antithrombotic therapy after LAAO. JACC 2022;79:1785–98.Mesnier J, et al. Early nonprocedural bleeding after LAAO. JACC:Interventions 17;5.Lo Russo GV, et al. Impact of early bleeding on long term mortality after LAAO. H Rhythm 22;2:409–502.