Q: Which of the following has the highest chance of chemical cardioversion of atrial fibrillation

A) Ibutilide
B) Esmolol
C) Esmolol plus ibutilide
D) Digoxin


Answer: C

Esmolol plus ibutilide has shown higher chances of chemical conversion of recent-onset atrial fibrillation in comparison to ibutilide monotherapy alone. This is probably due to the fact that esmolol decreases the ventricular response. The slower the ventricular rate at the time of ibutilide administration, the greater is the probability of conversion to sinus rhythm. Moreover, combo therapy of esmolol and ibutilide  not only decreases the incidence of immediate atrial fibrillation recurrence but also the risk of torsade de pointes.

Digoxin has no direct role in chemical conversion of atrial fibrillation.


Reference:

Fragakis N, Bikias A, Delithanasis I, et al. Acute beta-adrenoceptor blockade improves efficacy of ibutilide in conversion of atrial fibrillation with a rapid ventricular rate. Europace 2009; 11:70.