OBJECTIVETo investigate the effect and safety of intravenous Guanfu Base A hydrochloride (GFA) in the treatment of ventricular arrhythmias.

METHODSPatients without severe structural heart disease presenting with equal or more than 150 premature ventricular contractions per hour and/or non sustained ventricular tachycardia in drug-free holter monitoring were recruited in this double blind randomized active-controlled study. Eligible patients were randomly assigned to receive GFA or propafenone intravenously by a proportion of 1:1 in a double-blind manner. Intravenous bolus of the study medicine was given, followed by maintenance infusion for 6 hours. 24 hours continuous electrocardiographic recordings were performed to evaluate the efficacy. Vital signs, electrocardiograms and adverse events were documented before, during and after drug administration.

RESULTSA total of 201 patients came from eight centres were randomized to GFA or propafenone group. The demographic characteristics, the extent of ventricular arrhythmias and baseline clinical findings were comparable between the two groups. There were no significant differences in the percentage of reducing premature ventricular contractions and the accumulated efficacy between two groups. GFA had tendency to be more effective than propafenone in reducing the number of ventricular ectopy (P = 0.0609). There were no significant differences in the onset of action after drug administration between two drugs. The tolerance of GFA was better than propafenone. The adverse events in GFA group were less severe than those in propafenone group.

CONCLUSIONSIntravenous GFA in controlling the premature ventricular contraction has comparable effect to IV propafenone. Tolerance of GFA was better than propafenone.