Peridevice Leak After Transcatheter Left Atrial Appendage Occlusion: An Analysis of the Amulet IDE Trial

Background: Peridevice leak (PDL) is a limitation of left atrial appendage occlusion.

Objectives: The aim of this study was to assess the incidence of and outcomes associated with PDL in the Amulet IDE (AMPLATZER™ Amulet™ LAA Occluder Trial) randomized controlled trial.

Methods: Patients with atrial fibrillation at increased stroke risk were randomly assigned to undergo either Amulet (dual occlusive mechanism) or Watchman 2.5 (single occlusive mechanism) device implantation. Transesophageal echocardiography was performed at 45 days and 12 months postprocedure. Clinically significant PDL was defined as ≥3 mm. The primary endpoint was ischemic stroke or systemic embolism, and the secondary endpoint was stroke, systemic embolism, or cardiovascular death. The Kaplan-Meier method was used to estimate 18-month cumulative event rates landmarked at day 45 postprocedure.

Results: A total of 1,593 patients underwent successful left atrial appendage occlusion and had an evaluable transesophageal echocardiographic studies at 45 days. The dual-occlusive mechanism device provided superior closure (defined as leak <3 mm) compared with the single-occlusive mechanism device at 45 days (88.9% vs 74.1%; P < 0.01) and 12 months (90.5% vs. 78.3%; P < 0.01). Through 18 months, PDL was associated with a higher, but not statistically significant, risk for the primary endpoint (3.6% vs 1.8%; adjusted HR: 1.98; 95% CI: 0.93-4.19; P = 0.07) and a statistically significantly higher risk for the secondary endpoint (8.1% vs. 4.7%; adjusted HR: 1.66; 95% CI: 1.02-2.69; P = 0.04).

Conclusions: The dual-occlusive mechanism device provided superior closure compared with the single-occlusive mechanism device at both 45 days and 1 year postprocedure. PDL ≥3 mm was associated with a significantly increased 18-month risk for the composite of stroke, systemic embolism, or cardiovascular death. Completeness of closure of the left atrial appendage has important implications for patient outcomes. (AMPLATZER™ Amulet™ LAA Occluder Trial [Amulet IDE]; NCT02879448).