Background: Nifekalant hydrochloride (NIF) is an intravenous class-III antiarrhythmic agent that purely blocks the K(+)-channel without inhibiting β-adrenergic receptors. The present study was designed to investigate the feasibility of NIF as a life-saving therapy for out-of-hospital ventricular fibrillation (VF).
Methods and results: The Japanese Population-based Utstein-style study with basic and advanced Life Support Education study was a multi-center registry study with 4 participating institutes located at the northern urban area of Osaka, Japan. Eligible patients were those treated with NIF because of out-of-hospital VF refractory to 3 or more precordial shocks and intravenous epinephrine. Between February 2006 and February 2007, 17 patients were enrolled for the study. The time from a call for emergency medical service to the first shock was 12(6-26)min. The time from the first shock to the NIF administration was 25.5(9-264)min and the usage dose of NIF was 25(15-210)mg. When excluding 3 patients in whom percutaneous extracorporeal membrane oxygenation was applied before NIF administration, the rate of return of spontaneous circulation was 86% and the rate of admission alive to the hospital was 79%. One patient developed torsade de pointes.
Conclusions: Intravenous administration of NIF seems to be feasible as a potential therapy for advanced cardiac life-support in patients with out-of-hospital VF, and therefore further study is warranted.