Abstract 12449: Association of Left Atrial Function With Mitral Regurgitation Progression: Atherosclerosis Risk in Communities Study

Abstract

Background: Left atrial (LA) enlargement and atrial fibrillation (AF) are associated with functional mitral regurgitation (MR). It is unknown whether lower (worse) LA function is associated with MR progression, independent of LA size, in individuals without AF. Hypothesis: We hypothesized that lower LA function was associated with higher odds of MR progression. Aims: To evaluate the association of echocardiographic-based LA function with MR progression in the Atherosclerosis Risk in Communities (ARIC) Study, a community-based cohort. Methods: We included 2,444 ARIC participants (mean age, 73.8 ± 4.4 years, 42% male, 21% Black) who underwent 2D-echocardiogram at visits 5 (2011-2013) and 7 (2018-2019) and excluded those with AF, heart failure, and heart valve surgery at visit 5. Based on American College of Cardiology/American Heart Association guidelines, MR was graded as stages A-D. MR progression was defined as new onset of MR at visit 7, any increase in MR stage, or mitral valve surgery for MR between visit 5 and 7. LA function was measured using strain analysis and included reservoir, conduit, and contractile strain. Logistic regression models were used for the analysis. Results: After mean follow up of 6.5 ± 2.4 years, MR progression occurred in 504 (21%) participants. As shown in the table, lower reservoir strain was associated with higher odds of MR progression (OR [95% CI] per SD decrement, 1.16 [1.003, 1.34]) after adjusting for demographics, clinical risk factors, LA size and LV mass and function. LA conduit and contractile strain were not significantly associated with MR progression. Conclusion: Lower LA function is associated with higher odds of MR progression, independent of LA size, in individuals without AF. More research is needed to clarify the mechanism to identify novel prevention strategies for MR progression.