A postimplantation peridevice leak (PDL) of ≤5 mm (PDL≤5) was considered adequate for left atrial appendage (LAA) “closure” in the U.S. Food and Drug Administration (FDA) clinical studies of LAA closure. However, the therapeutic effects of these PDLs on future thromboembolism were not well understood. Researchers sought to evaluate PDL-5’s effect on clinical outcomes following Watchman device installation.

They assessed patients with successful device implantation for PDL using protocol-mandated transesophageal echocardiograms (TEEs) at 45 days and 1 year. They 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). Five-year results were analyzed in relation to the presence or lack of PDL≤5.

The group had 1,054 patients with a mean age of 74±8.3 years, a male predominance of 65%, and a CHA2DS2-VASc  of 4.1±1.4. At 45 days, TEE imaging indicated 634 patients (60.2%) without and 404 (38.3%) with PDL≤5, and at 1 year, 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 linked to a higher risk of ischemic stroke or systemic embolism over the course of 5 years (adjusted HR: 1.94; 95% CI: 1.15-3.29; P=0.014), which was primarily driven by an increase in non-disabling stroke (HR: 1.97; 95% CI: 1.03-3.78; P=0.04), whereas disabling or fatal stroke rates were similar (HR: 0.69; 95% CI: 0.19-2.46; P=0.56). The risk of fatal or disa PDL≤5 was not linked to an increased risk of all-cause mortality (HR: 0.87; P=0.42) or cardiovascular or unexplained death (HR: 1.20; P=0.45).

PDL≤5 after 1 year following Watchman device-assisted percutaneous LAA closure was linked to higher thromboembolism, driven by higher non-disabling stroke, but equivalent mortality.

Reference: jacc.org/doi/10.1016/j.jacc.2022.04.062