Prognostic value of the left atrioventricular coupling index in patients with chronic heart failure: a comparative echocardiographic analysis

Abstract Introduction The left atrioventricular coupling index (LACI), defined as the ratio between minimum left atrial volume and left ventricular end-diastolic volume (LVEDV) may reflect left atrioventricular coupling dysfunction and could potentially serve as a predictor of clinical outcomes. Indeed, prior studies have shown that LACI is independently associated with cardiovascular outcomes in healthy individuals and specific scenarios as after acute myocardial infarction and hypertrophic cardiomyopathy. However, its prognostic significance in patients with chronic heart failure (HF) remains to be fully elucidated. Purpose To evaluate the prognostic value of LACI in patients with chronic HF and to compare its predictive accuracy with other established echocardiographic parameters. Methods Retrospective study. We included consecutive patients with chronic HF referred to the echocardiography laboratory between January 2023 and April 2024. All patients had a minimum follow-up of one year, with the primary prognostic endpoint being a composite of all-cause mortality and HF hospitalization. The predictive accuracy of LACI was evaluated using ROC curve analysis. Results A total of 156 patients were included. Table 1 summarizes baseline characteristics. The mean follow-up duration was 631 ± 227 days. During follow-up, 30 patients (19%) met the primary endpoint. Univariate analysis showed that higher E/A ratio (1.9 vs. 0.9; p=0.009), higher E/E’ ratio (13.8 vs. 9.6; p=0.006), higher biplane indexed left atrial volume (BpLAiVol) (66.7 vs. 41.7 mL/m²; p0.001), higher LACI (0.5 vs. 0.4; p=0.021), lower Left ventricular ejection fraction (LVEF) (32.6% vs. 42.5%; p0.001) and higher Tricuspid regurgitation maximum velocity (TRvel) (2.9 vs 1.9m/s, p0.001) and male gender (23% vs. 8%; p=0.029) were associated with the primary outcome. However, only TRvel showed to be an independent predictor for the primary outcome (p=0.032). Regarding predictive accuracy, LACI demonstrated moderate discriminative ability, (AUC 0.690). When compared with other parameters, LACI showed inferior performance to E/E’ ratio (AUC 0.730), E/A ratio (AUC 0.726), BpLAiVol (AUC 0.856) and TRvel (AUC 0.856). In comparison with LVEF (based on 1-AUC=0.703), LACI had similar prognostic accuracy. Conclusion In chronic HF, LACI demonstrated moderate prognostic utility in predicting adverse outcomes, although it was inferior to E/E’ ratio, E/A ratio, BpLAiVol and TRvel. Notably, TRvel was identified as an independent predictor of adverse outcomes, underscoring its importance in risk stratification These findings suggest that while LACI provides valuable insights into atrioventricular coupling, its standalone prognostic utility remains limited compared to traditional echocardiographic indices. Integrating TRvel with other parameters may enhance clinical risk assessment, but further prospective studies are needed to validate these findings and optimize prognostic models in chronic HF.Table1