[Treatment of ventricular arrhythmia resistant to sodium channel blockaders]

The efficacy of antiarrhythmic agents of various groups (Na(+)- and Ca(2+)-channel blockers, cordarone) was comparatively evaluated in the same patients with ventricular arrhythmias. Cordarone and Na(+)-channel blockers were equally effective, whereas verapamil was significantly less potent. Then the antiarrhythmic efficacy of verapamil and cordarone was assessed individually in rhythm disturbances responsive to Na(+)-channel blockers and resistent to their action. The efficacy of verapamil was significantly higher in patients resistant to Na+ blockers than in those responsive to them. The action of cordarone was equal in these two groups of patients, however, it occasionally abolished arrhythmias resistant to both Na(+)- and Ca(+)-current blockers. The findings suggest the pattern of choosing antiarrhythmic therapy in ventricular arrhythmias.