Plasmatic NT-proBNP is strongly associated with atrial fibrillation in patients without severely reduced left ventricular ejection fraction in an ICD collective

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, a recent analysis showed a strong association of plasmatic NT-proBNP and atrial fibrillation (AFib). Aim of the study was to assess the association of plasmatic NT-proBNP depending on left ventricular ejection fraction (LVEF) in a cohort of patients with implantable cardioverter defibrillator (ICD). Methods 412 patients were included in the study. Blood samples were used to assess plasmatic NT-proBNP. Follow-up was performed after 45 months. LVEF was estimated by echocardiography according to Simpsons’ method. At enrollment, a 12-lead electrocardiogram was performed (sinus rhythm (SR, n = 306), atrial fibrillation (AFib, n = 79)). Patients were divided into two subgroups by LVEF of 40%. Results Patients suffering from severely reduced LVEF ≤ 40% showed significant higher age, higher rates of chronic kidney disease, diabetes, coronary artery disease, primary prevention ICD indication, coronary artery disease, dilatative cardiomyopathy and plasmatic NT-proBNP compared to patients with LVEF > 40% (each p < 0.05). There were no differences regarding hypertension and occurrence of AFib between patients with LVEF ≤ 40% compared to patients with LVEF < 40% (each p = n.s.). In ROC analysis there was a significantly higher AUC in patients with LVEF > 40% (AUC: 0.87, IQR 0.82-0.92) compared to patients with severely reduced LVEF ≤ 40% (AUC: 0.72, IQR 0.64-0.80) regarding plasmatic NT-proBNP and prediction of AFib (p < 0.002). In patients with LVEF > 40% plasmatic NT-proBNP was shown as significant predictor regarding existence of atrial fibrillation in binary logistic regression analysis, beside age (p < 0.05). Diabetes, hypertension, serum creatinine, coronary artery disease and primary prevention ICD indication were no significant predictors (p = n.s.). In patients with LVEF ≤ 40% plasmatic NT-proBNP was not shown as significant predictor regarding existence of atrial fibrillation in binary logistic regression analysis. Conclusion Elevated levels of plasmatic NT-proBNP are strongly associated with the prevalence of atrial fibrillation in patients without severely reduced LVEF in a cohort of ICD patients.