A novel clock-face method for characterizing peridevice leaks after left atrial appendage occlusion

To propose a novel method for mapping leak location and frequency to a clock-face representation of the left atrial appendage (LAA) ostium.

LAA occlusion with the Watchman device (WD) is an established therapy to reduce thromboembolic events in patients with atrial fibrillation (AF) and intolerance to long-term oral anticoagulation. Postimplantation leaks are known sequelae, but leak locations and characteristics are poorly described.

We retrospectively reviewed 101 consecutive WD implants from April 2015 to February 2018. Leak locations from 6-week post-implant transesophageal echocardiograms were mapped to a clock-face representation of the LAA ostium: 12:00 as cranial near the limbus, 3:00 as anterior toward the pulmonary artery, 6:00 as caudal near the mitral annulus, and 9:00 as posterior. Patient demographics, LAA dimensions, and procedural characteristics were also collected.

Thirty-four patients had ≥1 leak totaling 45 leaks at 6-week follow-up. Baseline patient demographics showed a mean age 77, CHA₂ DS₂ VASc 4.69, and 64% of patients with permanent AF. No patient had a detectable leak at the time of implant. At 6 weeks, mean leak size was 2.67 ± 0.89 mm with no leak over 5 mm (largest 4.60 mm). Most leaks occurred along the posterior 6:00-12:00 segment (39/45) and the 6:00-9:00 quadrant (16/45).

Six-week post-WD implant leaks localize to the posterior LAA ostium. This could result from the elliptical LAA orifice, differential LAA tissue composition, or implantation technique. This study provides a novel method for describing the location of post-implant leaks and serves as the basis for further investigations.