Abstract 13463: Left Atrioventricular Coupling Index as a Prognostic Marker: The Multi-ethnic Study of Atherosclerosis
Introduction: The left atrium (LA) and left ventricle (LV) parameters have both prognostic value for cardiovascular (CV) events. We hypothesize the left atrioventricular coupling to be a strong predictor of CV events. Hypothesis: This study aimed to investigate the prognostic value of a novel left atrioventricular coupling index (LACI) and to assess its predictive value for CV events in a population without a history of CV diseases at baseline. Methods: A total of 4,124 participants in the Multi-Ethnic Study of Atherosclerosis (MESA) underwent a cardiac MRI study. The LACI was defined by the ratio of the LA end-diastolic volume divided by the LV end-diastolic volume by MRI. Cox proportional hazard models were built to predict the endpoints of atrial fibrillation (AF), heart failure (HF), CV death and hard CV disease (CVD) defined by myocardial infarction, resuscitated cardiac arrest, fatal and non-fatal stroke or CV death. In univariable and multivariable Cox analyses, the association between LACI and time-to-event was analysed, adjusting for 14 covariables including traditional CV risk factors and biomarkers. Results: A total of 1151 CV events were observed during a median (IQR) follow-up period of 15.9 (12.9-16.6) years. LACI was associated with AF (HR 2.14, 95%CI [1.97-2.32]), HF (HR 1.70, 95%CI [1.56-1.86]), hard CVD (HR 1.34, 95%CI [1.22-1.48]), and CV death (HR 1.53, 95%CI [1.38-1.70]; for all p<0.0001). In multivariate analysis, LACI had a significant independent association for AF (HR 1.86, 95%CI [1.69-2.04]), HF (HR 1.47, 95%CI [1.33-1.60]), hard CVD (HR 1.25, 95%CI [1.12-1.40]), and CV death (HR 1.29, 95%CI [1.15-1.50; for all p<0.001). LACI showed better discrimination than the multivariate model for AF (C-statistic: 0.84 vs 0.79), HF (0.82 vs 0.80), hard CVD (0.77 vs 0.76), and CV death (0.84 vs 0.83). Conclusions: The LACI is a predictor of incident HF, AF, hard CV disease, and CV death in MESA.