Abstract 15021: Echocardiographic Measures of Cardiac Structure and Function are Associated with Risk of Atrial Fibrillation in Blacks: The Atherosclerosis Risk in Communities (ARIC) Study

Abstract

Background: Several studies have examined the link between various echocardiographic measures of cardiac structure and function, and atrial fibrillation (AF) in Caucasians and other populations but not in blacks.

Methods: We examined the association of several echocardiographic measures with incidence of AF in 2283 black participants (64.5% women, mean age 58.8 years) free of AF in the Jackson cohort of the ARIC study, a prospective study of cardiovascular disease in middle aged adults. Echocardiography was performed in 1993-1995 (only in the Jackson cohort) and incident AF was determined by electrocardiograms (ECG) at follow-up study exams, hospital discharge records or death certificates through the end of 2009. Cox proportional hazards regression was used to estimate hazard ratios and 95% confidence intervals for AF associated with the echocardiographic parameters modeled separately as categorical variables and as quintiles. Cox models were adjusted for sex, and the CHARGE AF risk score (comprising known AF predictors).

Results: During a total 30,826 (mean 13.5) person-years of follow up, 191 (8.4%) individuals developed AF. A significant association was identified between several echocardiographic markers of cardiac structure and function, and incident AF (table). Left ventricular (LV) size displayed a U-shaped relationship with risk of AF. Left atrial size displayed a nonlinear association. LV mass was associated positively with AF risk in hypertensive but not in non-hypertensive participants (p for interaction=0.04). Finally, mitral early-to-late (E/A) diastolic filling velocity ratio <0.7 and >1.5, and reduced ejection fraction were also associated with higher AF risk.

Conclusion: In a community based population of middle aged blacks, echocardiographic measures of cardiac structure and function are significantly associated with an increased risk of AF. The findings are similar to those in Caucasians.