Abstract 11223: Left Atrial Volumetric/Mechanical Coupling Index: A Novel Predictor of Clinical Outcomes in Heart Failure With Preserved Ejection Fraction

Abstract

Background: Left atrial (LA) dysfunction is common in heart failure with preserved ejection fraction (HFpEF). A higher LA volumetric/mechanical coupling index (LACI), calculated as the LA volume index (LAVI) divided by the diastolic late mitral annular velocity (a’), corresponds to weaker atrial mechanical activity for a larger volume index. Recently, the prognostic importance of the LACI has been reported in patients with heart failure with reduced ejection fraction, but data in patients with HFpEF are limited. Purpose: To investigate whether the LACI is associated with prognosis in patients with HFpEF. Methods: An analysis was performed from a prospective multicenter observational registry for HFpEF (PURSUIT-HFpEF Registry) conducted in the Osaka region of Japan. A total of 1231 patients hospitalized for acute heart failure (diagnosed by using Framingham criteria) met the inclusion criteria: a left ventricular ejection fraction (LVEF) ≥50% and brain natriuretic peptide ≥100 pg/ml. After excluding patients with persistent atrial fibrillation, we enrolled 508 patients (age, 80±10 years; females, 58.9%; paroxysmal atrial fibrillation, 18.5%) whose LAVI and a’ at discharge were available. Heart failure hospitalizations and cardiovascular deaths were the primary endpoint. Results: There was a weak negative correlation between the LAVI (median 42, interquartile range [IQR] 32-55 ml/m 2 ) and a’ (median 6.9, IQR 5.3-8.6 cm) (r=-0.26, p <0.001). As a result, the overall LACI was 6.28 (IQR 4.11-9.46). During a median follow-up of 729 (IQR 407-1180) days after discharge, 171 patients experienced the primary endpoint. The incidence incrementally increased with the LACI quartile groups (Q1: 22.1%, Q2: 33.1%, Q3: 38.6%, Q4: 40.9%, log-rank p = 0.003). After adjusting for age, gender, body mass index, left ventricular filling pressure, and serum brain natrium peptide levels, the LACI (hazard ratio, 1.18 per quartile increase; 95% confidence interval, 1.00-1.38; p = 0.045) was a significant predictor of the primary endpoint. Conclusions: The LA mechanical activity decreased with enlargement of the left atrium. The LACI was a novel index for predicting clinical outcomes in patients with HFpEF