Plasmatic NT-proBNP is strongly associated with atrial fibrillation in patients with Implantable cardioverter defibrillator

Abstract Background and objectives Atrial fibrillation is common in patients with chronic heart failure and associated with poor outcome in these patients. Plasmatic NT-proBNP represents the gold standard biomarker for chronic heart failure. Further, recent studies showed prognostic impact of urinary NT-proBNP. Aim of the study was to assess the association of plasmatic as well as urinary NT-proBNP and atrial fibrillation in a cohort of patients with implantable cardioverter defibrillator (ICD). Methods 412 patients were included in the study. Fresh spot urine and blood samples were used to assess urinary as well as plasmatic NT-proBNP. Urinary NT-proBNP was normalized to urinary creatinine. Follow-up was performed after 45 months. Heart rhythm history was evaluated and a 12-lead electrocardiogram was performed at enrollment (sinus rhythm (SR, n = 306), atrial fibrillation (AFib, n = 79)). Results Patients suffering from atrial fibrillation showed significant higher age, reduced left ventricular ejection fraction (LVEF), higher rates of chronic kidney disease, hypertension and urinary as well as plasmatic NT-proBNP compared to patients with sinus rhythm (each p < 0.05). There were no differences regarding Diabetes, primary prevention ICD indication, coronary artery disease and dilatative cardiomyopathy (each p = n.s.). In ROC analysis, plasmatic NT-proBNP showed promising predictive values regarding AFib (AUC: 0.80, IQR 0.76-0.85, p < 0.001) as well as urinary NT-proBNP (AUC: 0.76, IQR 0.71-0.81, p < 0.001). There was no significant difference between plasmatic and urinary NT-proBNP according to ROC analysis (p = n.s.). Plasmatic NT-proBNP was shown as a significant predictor regarding existence of atrial fibrillation in binary logistic regression analysis, beside age (p < 0.05). Diabetes, hypertension, serum creatinine, LVEF, coronary artery disease and primary prevention ICD indication were no significant predictors (p = n.s.). Urinary NT-proBNP was not shown as a significant predictor regarding existence of atrial fibrillation in binary logistic regression analysis (p = n.s.). Conclusion Elevated levels of plasmatic NT-proBNP are strongly associated with the prevalence of atrial fibrillation in a cohort of ICD patients.