Direct Comparative Safety and Anatomical Performance of Amulet Versus Watchman Devices for Left Atrial Appendage Occlusion.

Atrial fibrillation (AF) is associated with increased risk of cardioembolic events, particularly ischemic stroke, and left atrial appendage (LAA) occlusion devices have emerged as alternatives to long-term anticoagulation in high-risk patients. This systematic review evaluates the comparative safety and anatomical performance of the Amplatzer Amulet (Abbott, Chicago, IL, US) and Watchman (Boston Scientific, Marlborough, MA, US) devices based on two head-to-head randomized controlled trials (RCTs), Amulet IDE (investigational device exemption) and SWISS-APERO, which provided complete follow-up data on clinical and procedural outcomes. Stroke incidence, major bleeding, and cardiovascular or all-cause mortality were similar between devices, reflecting comparable safety profiles. However, anatomical outcomes differed, with the dual-seal design of Amulet achieving lower rates of peri-device leaks, suggesting a potential structural advantage. Complementary studies addressing procedural techniques, arrhythmia recurrence, and post hoc mechanistic analyses were discussed to contextualize these findings, though they were excluded from primary quantitative synthesis due to heterogeneity in endpoints and follow-up. Methodological limitations, including small sample sizes, variable outcome definitions, and reliance on the Jadad scale for risk-of-bias assessment, constrain the generalizability of results. Despite these limitations, this review provides an updated synthesis of contemporary evidence on LAA closure, highlighting that both devices are effective in reducing thromboembolic risk while emphasizing the importance of procedural strategy, operator experience, and device-specific anatomical considerations in optimizing outcomes.