Morphologic remodeling of left atrial appendage in patients with atrial fibrillation.

Background: Left atrial appendage (LAA) has recently been of significant focus because of the development of the LAA closure device.

Objective: The purpose of this study was to test the hypothesis that atrial fibrillation (AF) leads to a morphologic change in the LAA and to investigate the characteristics of LAA morphology in patients with and without AF.

Methods: This retrospective study included 225 patients (persistent AF [PeAF], n = 76; paroxysmal AF [PAF], n = 70; control, n = 79] who underwent echocardiography and computed tomography (CT). All patients were classified into 2 types (chicken wing [CW] or non-chicken wing [non-CW]) using CT.

Results: The prevalence of non-CW-type LAA was 39.5%, 15.7%, and 8.9% in the PeAF, PAF, and control groups, respectively. Patients in the PeAF group had a higher prevalence of non-CW-type LAA than did those in the PAF and control groups (P = .0014 and P <.0001, respectively). In addition, all patients were divided into 5 groups based on the type of cardiac rhythm (PeAF, PAF, or sinus rhythm) and left atrial volume index (cutoff value; 34 mL/m(2)): group A (Control), group B (PAF/Small-LA), group C (PAF/Large-LA), group D (PeAF/Small-LA), group E (PeAF/Large-LA). The prevalence of non-CW-type LAA was 9%, 14%, 17%, 29%, and 41% in groups A, B, C, D, and E, respectively.

Conclusion: Presence of persistent AF was associated with a higher prevalence of non-chicken wing-type LAA. Our analysis suggests that remodeling in patients with persistent AF can lead to a change in LAA morphology.