Correlation of Left Atrial Volume Index with Estimated Glomerular Filtration Rate in Chronic Kidney Disease: A Cross-Sectional Echocardiographic Study.

INTRODUCTION

Chronic kidney disease (CKD) drives progressive left heart remodeling through volume overload, inflammation, and hemodynamic stress, manifesting as left atrial enlargement and diastolic dysfunction. This cross-sectional study evaluated correlations between estimated glomerular filtration rate (eGFR) and left heart echocardiographic parameters-including left atrial volume index (LAVi), E/e' ratio, and atrial filling-related parameters-in CKD stages 2-4 to assess their utility as rapid, non-invasive predictors of renal function decline, particularly in emergency settings without laboratory access.

METHODS

100 consecutive CKD patients (eGFR < 60 mL/min/1.73 m², excluding LVEF < 35%, atrial fibrillation, poor acoustic windows) underwent transthoracic echocardiography (Philips EPIQ CVx) at Modarres Hospital, Tehran (2020-2021). Confirmed left heart parameters included: LAVi (biplane area-length method, indexed to BSA); E/e' ratio (pulsed-wave mitral E-velocity ÷ septal tissue Doppler e'-velocity); atrial filling parameters per ASE guidelines. eGFR calculated via CKD-EPI. Statistical analysis comprised Pearson/Spearman correlations, t-tests/Mann-Whitney U, and ROC curves (SPSS v22, P < .05).

RESULTS

Mean age 61.1 ± 12.7 years (65 males); eGFR 60.76 ± 14.15 mL/min/1.73 m². Strong inverse correlation: eGFR vs LAVi (r = -0.92, P < .001). Moderate inverse correlations: eGFR vs E/e' (r = -0.54, P < .0001). Atrial filling parameters progressively impaired with CKD advancement. LAVi demonstrated excellent discriminatory performance: AUC 0.98 (95% CI 0.97-1.00) for stage 2 vs 3-4; AUC 0.92 (95% CI 0.86-0.97) for stage 3. Optimal cutoffs: ≥ 30 mL/m² (sens 100%, spec 91.4%); ≥ 41 mL/m² (sens 100%, spec 97.9%). Performance robust across LVEF subgroups.

CONCLUSION

LAVi, E/e', and atrial filling parameters exhibit strong, progressive correlations with eGFR decline in CKD, offering excellent bedside discrimination of disease stages independent of laboratory measures. These left heart indices support rapid cardio-renal risk stratification; multicenter longitudinal validation warranted.