Supraventricular arrhythmia, N-terminal pro-brain natriuretic peptide and troponin T concentration in relation to incidence of atrial fibrillation: a prospective cohort study

Abstract

Abstract Background Frequent supraventricular arrhythmia is associated with increased incidence of atrial fibrillation. However, it is unknown whether the prognostic significance of supraventricular arrhythmia is modified by plasma levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) or troponin T (TnT). This study examined the interrelationships between NT-proBNP, TnT levels and frequent supraventricular arrhythmia, and whether these biomarkers and a measure of frequent supraventricular arrhythmia could improve risk assessment for incidence of AF. Methods Supraventricular extrasystoles (SVEs) and supraventricular tachycardias were assessed from 24-h electrocardiograph recordings in 373 individuals initially without AF. Elevated NT-pro-BNP, TnT and SVEs was defined as a measurement in the top quartile of the study population distribution. Incident cases of AF were retrieved by linkage with the Swedish National Patient Register. Results During a mean follow-up of 15.4 years, 88 subjects had a diagnosis of AF. After multivariable adjustment, individuals with both elevated NT-proBNP and frequent SVEs had a significantly increased incidence of AF, compared to subjects without elevated NT-proBNP or frequent SVEs (hazard ratio (HR) 4.61, 95% confidence interval (CI) 2.45–8.69), and compared to individuals with either elevated NT-proBNP or frequent SVEs (both P < 0.05). HRs for frequent SVEs alone or elevated NT-proBNP alone were 2.32 (95% CI 1.33–4.06) and 1.52 (95% CI 0.76–3.05), respectively. The addition of NT-pro-BNP and SVEs to a validated risk prediction score for AF, CHARGE-AF, resulted in improved prediction (Harrell’s C 0.751 (95% CI 0.702–0.799) vs 0.720 (95% CI 0.669–0.771), P = 0.015). Conclusion Subjects with both elevated NT-proBNP and frequent SVEs have substantially increased risk of AF, and the use of these variables could improve long-term prediction of incident AF.