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, 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.