Watchman outcomes comparing post-implantation anticoagulation with warfarin versus direct oral anticoagulants

As left atrial appendage occlusion devices (LAAO) implantation rates grow, continued evaluation on best patient practices is important. We report pooled Watchman outcomes at a multicenter Texas healthcare system with an emphasis on clinical outcomes and post-implantation anticoagulation with direct oral anticoagulants (DOACs) versus warfarin.

Data for 163 patients with atrial fibrillation (AF) undergoing Watchman implantation was collected via retrospective chart review between June 2016 and June 2018. A Fisher's exact test was utilized to evaluate associations in bivariate comparisons of categorical data. Tests of non-inferiority, applied between DOACs and warfarin, utilized a ratio of 2.

Outcomes were significant for similar rates of stroke, disabling stroke, major bleeds, and all-cause mortality when compared to published clinical trials. Most patients with cerebrovascular events were found to have >5 mm peri-device leaks (PDLs), were on warfarin at the time of the event (75%), and all occurred within the first 6 months post implant. A significant number of patients were discharged on DOACs (42%). DOACs were shown to be non-inferior to warfarin with respect to stroke (p = 0.0048), disabling stroke (p = 0.0383), gastrointestinal bleeding (p = 0.0287), mortality (p = 0.0165), and combined adverse outcomes (p = 0.0040). DOACs were associated with less combined adverse outcomes (p = 0.021).

Our findings suggest that additional imaging or aggressive management of PDLs in Watchman recipients within the initial 6-month follow-up may aid in reducing stroke rates. Additionally, anticoagulation with DOACs' post Watchman implantation was found non-inferior to warfarin, with some evidence of lower risk for adverse outcomes favoring DOACs.