Beta-blockers after Acute Coronary Syndrome: Does atrial fibrillation change the equation? A Portuguese multicentre national registry analysis

Introduction

Beta-blockers (BB) remain a cornerstone of secondary prevention after acute coronary syndrome (ACS). However, contemporary randomized trials have questioned their routine use in patients with preserved ejection fraction, often excluding those with atrial fibrillation (AF). We aimed to evaluate the prognostic impact of BB therapy after ACS and determine whether the presence of AF modifies its association with in-hospital and one-year mortality. Materials and Methods: We conducted a retrospective analysis of patients included in the Portuguese Registry of Acute Coronary Syndromes (ProACS), between October 2010 and 2021. Patients were stratified ac-cording to AF status and BB prescription. The two co-primary endpoints were in-hospital and one-year all-cause mortality.