Impact of Peridevice Leak on 5-Year Outcomes After Left Atrial Appendage Closure

Background: In the U.S. Food and Drug Administration (FDA) clinical trials of left atrial appendage (LAA) closure, a postimplantation peridevice leak (PDL) of ≤5 mm (PDL≤5) was accepted as sufficient LAA "closure." However, the clinical consequences of these PDLs on subsequent thromboembolism are poorly characterized.

Objectives: We sought to assess the impact of PDL≤5 on clinical outcomes after implantation of the Watchman device.

Methods: Using combined data from the FDA studies PROTECT-AF (Watchman Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation), PREVAIL (Evaluation of the Watchman Left Atrial Appendage Closure Device in Patients With Atrial Fibrillation vs Long Term Warfarin Therapy), and CAP2 (Continued Access to PREVAIL), we assessed patients with successful device implantation for PDL by means of protocol-mandated transesophageal echocardiograms (TEEs) at 45 days and 1 year. Five-year outcomes were assessed as a function of the absence or presence of PDL≤5.

Results: The cohort included 1,054 patients: mean age 74 ± 8.3 years, 65% male, and CHA₂DS₂-VASc 4.1 ± 1.4. TEE imaging at 45 days revealed 634 patients (60.2%) without and 404 (38.3%) with PDL≤5, and 1-year TEE revealed 704 patients (71.6%) without and 272 (27.7%) with PDL≤5. The presence of PDL≤5 at 1 year, but not at 45 days, was associated with an increased 5-year risk of ischemic stroke or systemic embolism (adjusted HR: 1.94; 95% CI: 1.15-3.29; P = 0.014), largely driven by an increase in nondisabling stroke (HR: 1.97; 95% CI: 1.03-3.78; P = 0.04), while disabling or fatal stroke rates were similar (HR: 0.69; 95% CI: 0.19-2.46; P = 0.56). PDL≤5 was not associated with an increased risk of cardiovascular or unexplained death (HR: 1.20; P = 0.45) or all-cause death (HR: 0.87; P = 0.42).

Conclusions: PDL≤5 at 1 year after percutaneous LAA closure with the Watchman device are associated with increased thromboembolism, driven by increased nondisabling stroke, but similar mortality. (Watchman Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation [PROTECT-AF; NCT00129545]; Evaluation of the Watchman Left Atrial Appendage Closure Device in Patients With Atrial Fibrillation vs Long Term Warfarin Therapy [PREVAIL; NCT01182441]; Continued Access to PREVAIL [CAP2; NCT01760291]).