The role of brain natriuretic peptide in atrial fibrillation: a substudy of the Substrate Modification with Aggressive Blood Pressure Control for Atrial Fibrillation (SMAC-AF) trial

Willy Weng,Rajin Choudhury,Isabelle Greiss,Anthony Tang,Jordan Bernick,Isabelle Nault,Lena Rivard,John Sapp,Jeff S Healey,Ratika Parkash

doi:10.1186/s12872-021-02254-5

Abstract

BackgroundCatheter ablation is an established therapy for atrial fibrillation but is limited by recurrence; efforts have been made to identify biomarkers that predict recurrence. We investigated the effect of baseline NT-proBNP on AF recurrence following catheter ablation in patients randomized to aggressive (< 120/80 mmHg) or standard blood pressure management (< 140/90 mmHg) in the Substrate Modification with Aggressive Blood Pressure Control trial (SMAC-AF).MethodsThe SMAC-AF study included 173 patients resistant or intolerant to at least one class I or III antiarrhythmic drug. We studied the effect of baseline NT-proBNP on the primary outcome of AF recurrence > 3 months post-ablation.ResultsOf the 173 patients, 88 were randomized to the aggressive cohort, and 85 into the standard group. The primary outcome occurred in 61.4% of those in the aggressive arm, versus 61.2% in the standard arm. In the aggressive group, logNT-proBNP predicted recurrence (HR 1.28, p = 0.04, adjusted HR 1.43, p = 0.03), while in the standard cohort, it did not (HR 0.94, p = 0.62, adjusted HR 0.83, p = 0.22). NT-proBNP ≥ 280 pg/mL also predicted occurrence in the aggressive (HR 1.98, p = 0.02) but not the standard cohort (HR 1.00, p = 1.00).ConclusionWe conclude that pre-ablation NT-proBNP may be useful in predicting recurrence in hypertensive patients and identifying patients who benefit from aggressive blood control and upstream therapies.Trial registration: NCT00438113, registered February 21, 2007.

Highlights

Radiofrequency catheter ablation has been established as a valuable therapeutic option for atrial fibrillation (AF), high rates of recurrence after ablationWeng et al BMC Cardiovasc Disord (2021) 21:445[4], and there has been developing interest in identifying biomarkers associated with fibrosis that may predict response to therapy for AF [5,6,7]
There was no difference in baseline NT-proBNP (p = 0.73), Left ventricular ejection fraction (LVEF) (p = 0.72), age (p = 0.70), sex (p = 0.51), AF duration (p = 0.14) or baseline systolic blood pressure (p = 0.67) between aggressive and standard groups
Patients in the aggressive blood pressure arm were treated for a median of 3.5 months before ablation; the standard blood pressure arm received usual care for a similar duration

Summary

Introduction

[4], and there has been developing interest in identifying biomarkers associated with fibrosis that may predict response to therapy for AF [5,6,7]. The randomized nature of SMAC-AF allows us to investigate how the association of NT-proBNP and outcomes differed with the effect of the additional blood pressure management. Catheter ablation is an established therapy for atrial fibrillation but is limited by recurrence; efforts have been made to identify biomarkers that predict recurrence. We investigated the effect of baseline NT-proBNP on AF recurrence following catheter ablation in patients randomized to aggressive (< 120/80 mmHg) or standard blood pressure management (< 140/90 mmHg) in the Substrate Modification with Aggressive Blood Pressure Control trial (SMAC-AF)

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