Abstract 18806: How Well Does Left Atrial Remodeling Predict Adverse Outcomes in Patients With Chronic Severe Aortic Regurgitation?

Abstract

Introduction: Aortic regurgitation (AR) leads to left ventricular (LV) remodeling by increasing LV load. We recently showed that LV dimensions, widely adopted marker of severe AR, are not reliable predictors of adverse CV outcomes in older patients and female sex. Here we sought to study the effects of chronic severe AR on left atrial (LA) size and function as a prognostic adjunct to LV dimensions. Methods: Adult patients with ≥3+ AR on routine surveillance with serial echocardiograms between 1/2010 and 12/2016 were included in this study. We assessed longitudinal trends of LA volume indexed to body surface area (LAVI) and LA reservoir strain (LAr) stratified by age and sex. Clinical endpoints included the occurrence of heart failure hospitalization, urgent aortic valve surgery, or all-cause mortality and were used to assess the prognostic value of our studied parameters. Results: A total of 525 patients with 1,687 serial echocardiograms conducted over a median (IQR) follow-up duration of 2.0 (1.0-3.6) years were included. As shown in figure 1, we observed a substantial increase in LAVI (1.0 [95% CI: 0.76-1.2] mL/m2 per year of follow-up) and a decrease in LAr (-1.3% [95% CI: -1.6 to -0.92%]) over the study period. There was no significant interaction related to sex or age (p ≥0.17). 210 adverse events were recorded and were significantly predicted by both LA parameters. Optimal discriminatory threshold for LAVI was determined to be 37 mL/m2 and LAr at 35% and were both found to be consistent across categories of sex and age. Conclusions: This study indicates that LA remodeling, unlike LV remodeling, shows a similar rate of progression across different categories of sex and age among patients with chronic severe AR. Furthermore, LA parameters provide an added prognostic value over LV parameters and may therefore be better suited to inform the timing of AR intervention.