Landiolol for refractory ventricular fibrillation in out-of-hospital cardiac arrest: a randomized, double-blind, placebo-controlled, pilot trial

Background Out-of-hospital cardiac arrest (OHCA) complicated by refractory ventricular fibrillation (VF) is associated with poor outcome. Beta-1-receptor selective blockade might overcome refractory VF and improve survival. This trial investigates the efficacy and safety of prehospital landiolol in OHCA and refractory VF. Methods In this randomized, double-blind, placebo-controlled pilot trial, patients with OHCA and recurrent or refractory VF (at least 3 defibrillation attempts and last rhythm shockable), pretreated with epinephrine and amiodarone, were allocated to receive add-on treatment with landiolol or placebo. Landiolol was given as a 20mg bolus infusion. The primary efficacy outcome was time from trial drug infusion to sustained return of spontaneous circulation (ROSC). Safety outcomes included the onset of bradycardia and asystole. Results A total of 36 patients were enrolled, 19 were allocated to the landiolol group and 17 to the placebo group. Time from trial drug infusion to sustained ROSC was similar between treatment groups (39 minutes [landiolol] versus 41 minutes [placebo]). Sustained ROSC was numerically lower in the landiolol group compared with the placebo group (7 patients [36.8%] versus 11 patients [64.7%], respectively). Asystole within 15 minutes of trial drug infusion occurred significantly more often in the landiolol group than in the placebo group (7 patients [36.8%] and 0 patients [0.0%], respectively). Conclusion In patients with OHCA and refractory VF who are pretreated with epinephrine and amiodarone, add-on bolus infusion of landiolol 20mg did not lead to a shorter time to sustained ROSC compared with placebo. Landiolol might be associated with bradycardia and asystole.