Residual echocardiographic and computed tomography findings after thoracoscopic occlusion of the left atrial appendage using the AtriClip PRO device.

Objectives: Thoracoscopic occlusion of the left atrial appendage (LAA) has become a routine part of thoracoscopic ablation for the treatment of atrial fibrillation (AF). Evaluation of residual findings of the occluded LAA by echocardiography has yet to be described.

Methods: Patients with AF indicated for hybrid ablation (thoracoscopic procedure followed by catheter ablation) were enrolled in this study. LAA was occluded as a routine part of the thoracoscopic procedure. Follow-up transoesophageal echocardiography was performed at the end of the procedure, 2-5 days and 2-3 months after the procedure (before the endocardial stage). The residual pouches of the LAA were measured in the mitral valve view (30-110°) and in the perpendicular view. The depth of the residual pouch was measured from the ostial plane (connecting the Coumadin ridge and the circumflex artery) to the deepest part of the residuum. The volume of the residual pouch and the distance from the circumflex artery to the proximal and the distal ends of the AtriClip were measured using computed tomography.

Results: Forty patients were enrolled in this study. The success rate for the occlusion of the LAA, assessed on transoesophageal echocardiography 2-5 days after surgery, was 97.5%. Regarding the residual findings, no reperfused LAAs were found, and only residual stumps remained. The depth of the stump was 12.9 ± 5.9 mm, the area was 2.2 ± 1.1 cm2, and the volume was 3.6 ± 1.9 ml (all data are shown as mean ± standard deviation).

Conclusions: The occlusion of the LAA using an AtriClip PRO device was a clinically safe procedure with high efficacy and was associated with the presence of a small residual pouch after occlusion.

Clinical Trial Registration: NCT02832206.