Safety of Intravenous Diltiazem in Reduced Ejection Fraction Heart Failure with Rapid Atrial Fibrillation.

BACKGROUND AND OBJECTIVE: Diltiazem is a nondihydropyridine calcium channel blocker that is used to control rapid ventricular response in patients who have atrial fibrillation or flutter. Diltiazem has a negative inotropic effect and may cause hemodynamic decompensation in patients with reduced ejection fraction. This study evaluated outcomes in patients who had low ejection fraction and were treated with diltiazem.

METHODS: This was a retrospective chart review in 635 patients who were hospitalized because of rapid atrial fibrillation and who were treated with intravenous diltiazem. Outcomes were evaluated for patients in two groups based on ejection fraction (EF): normal (EF ≥ 50%) and low EF (EF < 50%).

RESULTS: There were no differences in frequency of hypotension, intensive care unit transfer, or in-hospital mortality between the two groups. There was a significantly higher frequency of acute kidney injury within 48 h after starting diltiazem in patients who had low (16 patients [10%]) compared with normal EF (17 patients [3.6%] P = 0.002).

CONCLUSIONS: Intravenous diltiazem in patients who have decreased EF may be associated with increased risk of acute kidney injury, but not increased risk of hypotension, intensive care unit transfer, or in-hospital mortality.