Abstract 18545: Usefulness of Left Atrial Appendage Isolation for Maintenance of Sinus Rhythm in a Swine Model

    loading  Checking for direct PDF access through Ovid

Abstract

Introduction: A left atrial appendage (LAA) occlusion devices deployed percutaneously using epicardial approaches have been proposed as an alternative to therapeutic anti-coagulation for stroke prophylaxis. Furthermore, epicardial exclusion of the LAA has shown promising results in decreasing the burden of atrial fibrillation (AF). However, it is unclear a role of LAA for initiation and maintenance of paroxysmal AF.

Hypothesis: Therefore, we examined the relationship between an initiation or maintenance of AF and the role of LAA.

Methods: 1) We induced AF and measured a duration of AF by rapidly pacing in LAA distal, LAA proximal and right pulmonary vein (RPV) in 9 swine. Pacing cycle length (p-CL) were 70, 90, 110 and130 msec in each site. 2) Among 9 swine, 5 swine were performed LAA isolation using radiofrequency ablation. After LAA isolation, we induced AF and measured a duration of AF again.

Results: 1)By p-CL of 90 msec, duration of AF with LAA distal-pacing was significantly longer as compared with RPV-pacing (33.4±41.4 msec versus 3.9±4.2 msec, p=0.008). By p-CL of 110 and 70 msec, duration of AF with LAA distal-pacing tended to be longer as compared with RPV-pacing (15.8±15.3 msec versus 5.0±7.1 msec, p=0.07, 33.0±58.4 msec versus 7.7±14.9 msec, p=0.06). 2) Radiofrequency ablation All 5 swine completely isolated all 5 swine. AF induction times by rapidly pacing after LAA isolation were decreased before LAA isolation (6 times versus 13 times). By all p-CL, duration of AF after LAA isolation was significantly shorter as compared to those with before LAA isolation. One swine was induced and maintained LAA-tachycardia after LAA isolation, however sinus rhythm maintained in other places except LAA.

Conclusions: LAA plays a role for initiation and maintenance of paroxysmal AF. Complete electrical isolation of LAA from left atrium by LAA exclusion system might be achieve freedom from AF.

Related Topics

    loading  Loading Related Articles