Background: Cardiovascular disease is the leading cause of morbidity and mortality in pediatric patients with chronic kidney disease (CKD). However, the kidney-heart relationship in this population remains poorly understood, particularly in the context of dialysis modality and duration. This study aims to investigate the associations between estimated glomerular filtration rate (eGFR), left ventricular ejection fraction (LVEF), left ventricular (LV) mass, and dialysis modality and duration in pediatric CKD patients. Methods: This retrospective study included 16 pediatric CKD patients (median age 3.6 years; 31.3% female and 68.75% male), stratified by the presence of cardiac dysfunction (LVEF ≤ 50%). Clinical data, including eGFR, LVEF, LV mass, and dialysis history (hemodialysis or peritoneal dialysis), were collected. Independent T-tests, Wilcoxon Two-Sample tests, and Spearman's correlations were performed to assess renal and cardiac function relationships. Multivariate regression models were employed to evaluate predictors of LVEF over time. Results: Cardiac dysfunction was observed in 25% of the cohort, with significantly lower LVEF and fractional shortening compared to those without dysfunction. Patients with cardiac dysfunction were younger at CKD diagnosis (p < 0.0001), suggesting an earlier progression of renal and cardiac impairment. Following dialysis, eGFR significantly decreased in patients without cardiac dysfunction (p < 0.0001) but remained unchanged in those with dysfunction. Conversely, LVEF improved post-dialysis in patients with cardiac dysfunction (p = 0.0034) but remained stable in those with normal cardiac function. Prolonged dialysis duration was negatively correlated with eGFR (r = -0.31, p = 0.008) and LV mass (r = -0.26, p = 0.024). Hemodialysis duration was positively correlated with LVEF (r = 0.73, p < 0.001), suggesting potential cardiovascular benefits from prolonged hemodialysis treatment. Conclusions: Pediatric CKD patients, particularly those with cardiac dysfunction, experience significant alterations in both renal and cardiac parameters, requiring tailored dialysis strategies in this population.

The authors have declared no competing interest.

This study did not receive any funding

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The Conjoint Health Research Ethics Board of the University of Calgary gave ethical approval for this work

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