Diltiazem in Afib with RVR

Dr. Lily Cheng



After an IV diltiazem infusion load, will IV continuous or oral immediate-release diltiazem be more effective for acute heart rate control? 

KN Means, AE Gentry, TT Nguyen. IV Continuous Infusion vs. Oral Immediate-release Diltiazem for Acute Heart Rate Control. (Feb 2018). Western Journal of Emergency Medicine, Vol 19, No. 2 [paper]


This was a single-center, observational, retrospective study at a tertiary academic medical center. 111 patients were included with 41 patients in the PO group and 70 patients in the IV group. Inclusion criteria were ≥ 18 years old, heart rate ≥ 110, and received IV diltiazem load. Exclusion criteria were pregnancy, prisoners, or history of cardioversion or antiarrhythmic in prehospital or in the ED. Treatment failure was assessed after 4 hours to allow time for the IV and PO medication to achieve peak levels of effectiveness. Treatment failure was defined as heart rate ≥ 110, a switch from PO to IV infusion, addition of another IV bolus, or a switch to another rate control or antiarrhythmic.

Study Design


In the PO group, the average initial dose of diltiazem was 30-60mg and the length of stay of patients was a mean of 4.7 days and median 3 days. Treatment failure was 27% with an adjusted odds ratio 0.4 (95 CI [0.15, 0.94], p = 0.041). In the IV continuous infusion group, median dose was 10mg/hr (with a range of 2.5-20mg/hr) and the length of stay was a mean of 9 days and median 5 days. Treatment failure was 46%. No patients required vasopressors or had diltiazem discontinued due hypotension. 


PO immediate release diltiazem is associated with less treatment failure at 4 hours, higher odds to be admitted to the general medical floor and a shorter length of stay (by 2 days) than IV continuous diltiazem infusion.


¹ Wyse DG, Waldo AL, Dimarco JP, et al. A comparison of rate control and rhythm control in patients with atrial fibrillation. N Engl J Med. 2002;347(23):1825-33. [paper]

² Van gelder IC, Groenveld HF, Crijns HJ, et al. Lenient versus strict rate control in patients with atrial fibrillation. N Engl J Med. 2010;362(15):1363-73. [paper]