Outcomes of Left Atrial Appendage Occlusion Treatment With Amulet After Unsuccessful Watchman FLX Device: A Multicenter Observational Study

ABSTRACT Introduction Watchman FLX (W‐FLX) is the most widely used left atrial appendage occlusion (LAAO) device to prevent atrial fibrillation (AF) related strokes in the United States. However, successful LAAO with W‐FLX can be challenging in patients with complex left atrial appendage (LAA) anatomies. This analysis aimed to assess the procedural success rates of LAA occlusion (immediate and short‐term outcomes) using the Amulet device, in patients with prior failed LAAO with W‐FLX device. Methods and Results This was a multicentric retrospective analysis of 62 consecutive patients with unsuccessful LAAO with W‐FLX, who subsequently underwent an attempted Amulet occluder placement. The primary endpoint was successful Amulet implantation. Secondary endpoints included peri‐device leak (PDL) and device‐related thrombus assessed by transesophageal echocardiography (TEE) at 45 days, safety end point through 7 days or hospital discharge (whichever was later) and major adverse events (MAEs) through 45 days. The Amulet occluder was successfully implanted in 98.38% of patients ( n = 61/62). No clinically relevant PDL or device‐related thrombus was noted at 45 days. There was one pericardial effusion noted a week after Amulet implant that underwent successful percutaneous pericardiocentesis. The reasons for W‐FLX failure were all anatomical in nature. We identified five distinct anatomical patterns that posed challenges for W‐FLX deployment but were amenable to successful Amulet implantation. Conclusion The disc‐lobe design of Amulet allows a high degree of successful LAAO in challenging anatomical variants (whale‐tail, bilobed LAA, shallow vertical chicken‐wing or seahorse, oval wide with posterior sloping trabeculations, and extensively trabeculated broccoli morphologies) with prior failed W‐FLX implants. These findings may help guide device selection on pre‐LAAO imaging, thereby enhancing resource utilization and contributing to more efficient and safer LAAO procedures.