Unmasking the Epicardial Adipose Tissue‐Left Atrial Strain Nexus in HFpEF: A Potential Echocardiographic Signature of Cardiac Adaptation

PURPOSE: This study aims to investigate the relationship between epicardial adipose tissue (EAT) and left atrial function in patients with preserved ejection fraction heart failure (HFpEF). METHODS: We conducted a cross-sectional study involving 113 patients diagnosed with HFpEF and 48 control subjects without heart failure. Echocardiography was performed to assess EAT thickness and left atrial function was quantified using Autostrain left atrium (LA), including left atrial strain during reservoir phase (LASr), left atrial strain during conduit phase (LAScd), and left atrial strain during contraction phase (LASct). Clinical and biochemical parameters were correlated with EAT and LA strain using regression analyses and generating receiver operating characteristic (ROC) curves for left atrial strain parameters. RESULTS: EAT thickness was significantly greater in the HFpEF group (8.0 ± 1.0 mm) compared to the control group (5.0 ± 0.7 mm). HFpEF group exhibited poorer left ventricle diastolic function, indicated by lower e' velocity, E/A ratio, and higher E/e' values. Left atrial strain parameters, including LASr (22.4 ± 9.1%), LAScd (11.9 ± 6.9%), and LASct (10.5 ± 3.9%), were all lower in the HFpEF. EAT thickness was positively correlated with NT-proBNP, triglycerides, and fasting blood glucose. Multivariate analysis revealed significant associations between EAT and LA strain parameters even after adjusting for potential confounders. ROC curve analysis indicated that LASr had the highest diagnostic accuracy for HFpEF. Additionally, left atrial strain parameters were strongly correlated with left ventricular diastolic function. CONCLUSION: Patients with HFpEF exhibit increased EAT thickness and reduced left atrial function. The thickening of EAT is associated with a decrease in left atrial strain. LA strain, particularly LASr, may serve as a sensitive indicator for early detection of left ventricular diastolic dysfunction in HFpEF.