Atrial fibrillation associated with renal tubular injury in acute chest pain: N-acetyl-β-D-glucosaminidase, kidney injury molecule 1, and NT-proBNP as predictive markers.

INTRODUCTION: Acute heart disorders are often characterized by the coexistence of atrial fibrillation (AF) and cardiorenal syndrome. This study focused on evaluating the potential cardiorenal biomarkers N-acetyl-β-D-glucosaminidase (uNAG) and kidney injury molecule 1 (uKIM) in a real-world chest pain cohort according to the presence of sinus rhythm (SR) and AF. METHODS: The urinary concentrations of uNAG and uKIM were measured in 601 patients presenting with acute chest pain in the emergency department of the University Hospital Regensburg. RESULTS: Significantly increased uNAG, uKIM, and NT-proBNP concentrations were observed among 68 patients presenting with AF compared to 533 presenting with SR (each p < 0.001, AUCuNAG = 0.730, AUCuKIM = 0.634). Furthermore, patients diagnosed with acute coronary syndrome (ACS) showed significantly increased biomarker concentrations when presenting with AF compared to SR (each p < 0.05). Logistic regression revealed that uNAG, NT-proBNP and high-sensitivity troponin T were independent predictors of AF (p < 0.05), whereas eGFR and uKIM were not (each p = ns). CONCLUSIONS: In conclusion, NT-proBNP, uNAG, and to a lesser extent uKIM correlated with AF. NT-proBNP and uNAG presented as independent predictors of AF. The observational findings may be compatible with higher concentrations of tubular injury biomarkers in patients with acute heart disease presenting with AF compared to SR; however, causality cannot be established from this study design.