Photo Credit: Pornpak Khunatorn

The following is a summary of “Acute rate control with metoprolol versus diltiazem in atrial fibrillation with heart failure with reduced ejection fraction,” published in the May 2023 issue of Emergency Medicine by Kapustova, et al.

For a retrospective cohort study, researchers sought to compare the efficacy of parenteral metoprolol and diltiazem in achieving heart rate control in the acute management of atrial fibrillation (AFib) with the rapid ventricular response (RVR) in patients with heart failure with reduced ejection fraction (HFrEF). The study also aimed to identify safety outcomes associated with these medications.

This single-center cohort study included adult patients with HFrEF who received intravenous (IV) metoprolol or diltiazem for AFib RVR in the emergency department (ED). The primary outcome measure was rate control, defined as achieving a heart rate (HR) <100 bpm or an HR reduction ≥20% within 30 minutes of the first dose administration. 

Secondary outcomes included rate control within 60 and 120 minutes from the first dose, the need for repeat dosing, and patient disposition. Safety outcomes assessed included hypotensive and bradycardic events.

Among the 552 patients evaluated, 45 met the inclusion criteria, with 15 in the metoprolol group and 30 in the diltiazem group. Using the bootstrapping method, the study found that patients treated with metoprolol were equally likely to achieve the primary outcome compared to those treated with diltiazem (BCa 95% CI: 0.14, 4.31). There were no reported hypotensive or bradycardic events in either treatment group.

The study suggested that short-term use of diltiazem is as safe and effective as metoprolol in the acute management of patients with HFrEF and AFib RVR. The findings supported the use of non-dihydropyridine calcium channel blockers (non-DHP CCBs) such as diltiazem in the specific patient population.

Source: sciencedirect.com/science/article/abs/pii/S0735675723000876