Diagnostic Value of Left Atrioventricular Coupling Index and Left Atrial Stiffness Index for Left Ventricular Diastolic Dysfunction in Patients with Chronic Kidney Disease: A Comparative Study Based on the 2025 ASE Guidelines.

OBJECTIVE: To evaluate the diagnostic performance of the left atrioventricular coupling index (LACI) and left atrial stiffness index (LASI) for left ventricular diastolic dysfunction (LVDD) in patients with chronic kidney disease (CKD), using the 2025 American Society of Echocardiography (ASE) guidelines as the gold standard. METHODS: A total of 501 patients with CKD were prospectively enrolled. All participants underwent transthoracic echocardiography, and LACI and LASI were calculated. Univariate and multivariate logistic regression analyses were performed to identify independent predictors of LVDD. Using the 2025 ASE guidelines as the gold standard, we assessed the diagnostic performance and agreement of LACI and LASI for LVDD, and validated the findings in a validation cohort. Kaplan-Meier curves and the log-rank test were used to compare event-free survival among patients stratified by LACI and LASI levels. RESULTS: According to the 2025 ASE guidelines, 92 patients (18.4%) were diagnosed with LVDD. LACI and LASI were significantly higher in patients with LVDD and in those with pulmonary edema (P < 0.05), and increased with advancing NYHA functional class and CKD stage (P < 0.001). Both LACI and LASI correlated positively with age, NT-proBNP, and urinary albumin-to-creatinine ratio, and negatively with eGFR (all P < 0.001). Multivariate logistic regression showed that standardized LACI (OR 6.16, 95% CI: 4.25-8.92) and LASI (OR 33.75, 95% CI: 16.72-68.13) were independent predictors of LVDD. With the 2025 ASE guidelines as reference, the AUC for LACI was 0.860 (95% CI: 0.811-0.909) at a cutoff of 0.235, and for LASI was 0.921 (95% CI: 0.885-0.957) at a cutoff of 0.295. Both parameters exhibited good diagnostic performance for LVDD, which was further confirmed in an independent validation cohort. Furthermore, when using thresholds derived from a Chinese healthy population to reclassify LVDD, LACI and LASI retained good diagnostic performance, and their combination improved sensitivity while maintaining high specificity. Patients with LACI >0.235 and LASI >0.255 had significantly lower event-free survival than those with lower levels (log-rank P < 0.001). CONCLUSIONS: Using the 2025 ASE guidelines as the gold standard, both LACI and LASI demonstrate good diagnostic value for LVDD in patients with CKD, with LASI showing superior performance. The combined use of both parameters significantly improves diagnostic sensitivity.