diltiazem vs metoprolol for atrial fibrillation with rapid ventricular response in heart failure with reduced ejection fraction in emergency departments

Objective: as emergency department (ed) visits for atrial fibrillation (af) grow, comorbidities lead to challenging treatment scenarios. there are limited data evaluating the safety of diltiazem in the acute management of af with rapid ventricular rate (rvr) in patients with heart failure with reduced ejection fraction (hfref). the objective of this study was to evaluate the safety of diltiazem vs metoprolol in patients presenting to the ed with af with rvr with hfref. methods: this multicenter, retrospective, cohort study evaluated patients with af with rvr with hfref who received either intravenous (iv) diltiazem or metoprolol in the ed. the primary endpoint was worsening heart failure, defined as an increase in supplemental oxygen requirement, acute kidney injury (aki), or inotrope administration. secondary endpoints included bradycardia, systolic blood pressure (sbp) <90 mmhg, or atropine administration. results: of the 5,465 patients screened, 62 (1.1%) patients were included for analysis. forty-nine (79%) patients received iv diltiazem and 13 (21%) received iv metoprolol. the primary endpoint of worsening heart failure occurred in 26.5% in the diltiazem cohort and 15.4% in the metoprolol cohort (p=0.493). there were no differences in increased need for supplemental oxygen, incidence of aki, or inotropic support. there were no differences in the secondary safety endpoints. conclusion: for ed management of patients with af with rvr with hfref, treatment with iv diltiazem did not lead to an increase in worsening heart failure compared to iv metoprolol. future prospective trials are needed to evaluate this treatment approach in this population.