Association of albuminuria with left atrial remodeling and left ventricular diastolic function in non-dialysis chronic kidney disease patients

Background

Chronic kidney disease (CKD) is associated with early subclinical cardiac involvement, particularly left atrial (LA) remodeling and left ventricular (LV) diastolic dysfunction. Albuminuria is a well-established marker of cardiovascular risk in CKD; however, its relationship with echocardiographic markers of diastolic function and atrial remodeling in non-dialysis CKD populations.

Objective

To investigate the associations of renal function stage and albuminuria severity with LA remodeling and LV diastolic function parameters in a non-dialysis CKD population after strict exclusion of cardiac and systemic confounders.

Methods

This cross-sectional study included 300 non-dialysis CKD patients with an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m².

Patients were categorized according to eGFR as G3a (45–59; n=128), G3b (30–44; n=97), and G4–5 (<30; n=75). Albuminuria assessment was available in 275 patients and classified by albumin-to-creatinine ratio (ACR) as A1 (<30 mg/g; n=104), A2 (30–300 mg/g; n=83), and A3 (≥300 mg/g; n=88). Comprehensive transthoracic echocardiography was performed to assess LV diastolic function and LA structural parameters. Comparisons across ACR and eGFR categories, correlation analyses, and post hoc testing were conducted as appropriate.

Results

The mean age of the study population was 63.4 ± 12.2 years, and 59.3% were female. Hypertension was the most prevalent comorbidity (86%), followed by diabetes mellitus (38%).

Across albuminuria categories, progressive alterations in LV diastolic filling were observed. Mitral E-wave velocity and E-wave maximum gradient increased significantly from A1 to A3 (p=0.003 and p=0.010, respectively), while IVRT was shorter in A2 and A3 compared with A1 (p=0.039). In contrast, markers of impaired relaxation, including E/A ratio and septal and lateral e′ velocities, were similarly reduced across all ACR groups without significant intergroup differences.

LA structural remodeling showed a clear association with albuminuria severity. LAVmax, LA volume, and left atrial volume index increased progressively across ACR categories (all p<0.05), whereas LA anteroposterior diameter did not differ among groups.

Correlation analyses demonstrated significant positive associations between ACR and mitral E-wave parameters as well as LA volume indices, while IVRT showed a modest inverse correlation. When analyses were repeated across eGFR stages, no significant differences were observed in LV diastolic or LA structural parameters, except for LAVmax.

Conclusion

Albuminuria, rather than eGFR, emerged as the dominant determinant of early left atrial remodeling and diastolic filling abnormalities in non-dialysis CKD patients, highlighting its role as a sensitive marker of subclinical cardiorenal remodeling and a key tool for early cardiovascular risk assessment.For image description, please refer to the figure legend and surrounding text.For image description, please refer to the figure legend and surrounding text.