Abstract 19141: Natural History of Tricuspid Annulus and Right Atrial Remodeling in Permanent Atrial Fibrillation
Background: The natural history of tricuspid annulus and right atrial (RA) remodeling in patients with permanent atrial fibrillation (AF) has not been assessed. We aimed to determine the rate of change in tricuspid annulus diameter and RA volume in patients with permanent AF.
Methods: This cohort study included 160 patients with a history of permanent AF who had at least 2 transthoracic echocardiograms performed between 2005 and 2010 at Vancouver General Hospital in British Columbia. Patients with structural valve disease at onset, congenital heart disease, and patients with more than mild-moderate tricuspid or mitral regurgitation were excluded from analyses. The tricuspid annulus diameter, defined as the distance between the points of attachment of the anterior and septal tricuspid leaflets from the apical 4-chamber view, was measured during end-systole and end-diastole. Maximal RA size was measured in terms of RA volume using single plane Simspon’s method from 4 chamber view. Linear mixed effects modelling was used in analyzing the changes in measurements over time.
Results: Of the 160 subjects included in this analysis, 100 were men (62.5%). The mean age at study entry was 74±10 yrs. The median number of echocardiographic studies performed was 3 (range 2 - 6). All 160 patients showed progressive increase in tricuspid annulus diameter over time. There was a significant increase in tricuspid annulus diameter at end-systole and end-diastole over a mean follow up time of 3.2 ± 2.8 years. Respectively, the increase was 0.68 mm/ year, 95% CI
0.232 -1.02, P=0.0027) and end-diastole 0.63 mm/year, 95% CI 0.182-0.93, P=0.0015). Mean RA volume increased from a mean of 39 mL/m2 to 81 mL/m2 for the cohort, or 13 mL/m2 per year, which was significantly greater than the increase in left atrial volume (10 mL/m2 per year, P<0.001).
Conclusions: Permanent AF was associated with significant increase in tricuspid annulus diameter and RA volume over time. The rate of changes appeared greater on the right side than on the left. How these differential changes relate to the frequent findings of right heart failure in these patients warrant further investigations.
- © 2013 by American Heart Association, Inc.