Abstract 10162: NT-proBNP is Associated with Stroke, Heart Failure Hospitalizations, and Death in Patients with Atrial Fibrillation Without Oral Anticoagulation Regardless of Heart Rhythm

Abstract

Background: NT-proBNP is elevated in patients with a diagnosis of atrial fibrillation (AF) and associated with risk of stroke and other outcomes. The associations have mainly been studied in patients on oral anticoagulation and not considering if samples were obtained during AF or sinus rhythm. We investigated the association of NT-proBNP with heart rhythm and cardiovascular (CV) events in patients with AF without oral anticoagulation. Methods: Plasma samples were obtained at baseline in 3184 patients with diagnosis of AF (2142 in AF rhythm at blood sampling) receiving aspirin in two multicenter randomized clinical trials with median follow-up 1.2 years (AVERROES) and 3.8 years (ACTIVE A), respectively. NT-proBNP was analyzed using Elecsys electrochemiluminescence immunoassay. Association of NT-proBNP with clinical variables was assessed with multivariable linear regression models. Association with outcomes were estimated with Cox-regression models adjusting for clinical variables. Results: Median age was 71 years, 57.8% were men, and median NT-proBNP 713 ng/L (25 th -75 th percentiles, 282-1388 ng/L). Variables contributing to NT-proBNP level were, in reducing order: AF rhythm (ratio of geometric means 2.9), age, creatinine, and prior heart failure. Levels of NT-proBNP were significantly associated with ischemic stroke (HR 3 rd vs 1 st quartile 2.1, 95%CI 1.5-3.0), heart failure hospitalizations (HR 2.2, 95%CI 1.6-2.9), and CV death (HR 2.4, 95% CI 1.8-3.3), all p<0.001, without significant interaction with AF rhythm. Figure depicts NT-proBNP distribution by rhythm and association with ischemic stroke. Conclusion: In patients with a diagnosis AF, plasma levels of NT-proBNP are three times higher during AF rhythm compared with sinus rhythm. Higher levels of NT-proBNP are independently associated with ischemic stroke, heart failure hospitalizations, and CV death in AF patients without oral anticoagulation treatment, irrespective of heart rhythm.