Intraoperative Assessment of Left Atrial Diverticulum and Remnant Stump after Left Atrial Appendage Epicardial Occlusion.
OBJECTIVES
Epicardial left atrial appendage (LAA) closure with use of occluder is an emerging technique. Absence of remnant LAA stump is major criterion of successful obliteration. The aim of study was to assess early success rate of epicardial LAA closure.


METHODS
Fifteen patients with persistent AF and coronary artery disease underwent off-pump coronary revascularization with concomitant ablation and LAA epicardial occlusion with use of two types of occluders. Before incision and after appendage closure, TEE was performed to assess the LAA anatomy, diameter of left atrial ridge, and remnant LAA stump after occlusion.


RESULTS
In 80% (12) of patients, formation of a left atrial diverticulum was observed with the left atrial ridge forming the superior boundary. In 5 patients (33%), a minimal remnant LAA stump was found, none exceeding 1 cm (average length: 1.5 ± 2.3 mm). In all patients, blood flow in LAA cavity distal to the occluder was absent. There was no significant difference in LAA type, average left atrial diameter, LAA orifice, LAA length, left atrial ridge, or size of occluder used between patients with and without a remnant LAA stump. Occurrence of a remnant LAA stump correlated significantly with unfavorable anatomy (LAA orifice < 20 mm and LA ridge > 5 mm; r = 0.5774, P = 0.02).


CONCLUSION
The early success of epicardial LAA occlusion is not dependent on LAA morphologic type or occluder used. A minimal remnant LAA stump not exceeding 1 cm in length without distal blood flow was observed in one-third of the cases.