Effects of a new antiarrhythmic drug, SD-3212, on canine ventricular arrhythmia models.

The antiarrhythmic effects of a new antiarrhythmic agent, SD-3212, (-)-(S)-3,4-Dihydro-2-[5-methoxy-2-[3-[N-methyl-N-[2-[(3,4- methylene dioxy)phenoxy]ethyl]amino]propoxy]phenyl]-4-methyl-3-oxo-2H-1, 4-benzothiazine hydrogen fumarate, were investigated using canine models of ventricular arrhythmias, i.e. spontaneously occurring digitalis-, two-stage coronary ligation- and adrenaline-induced arrhythmias. SD-3212 suppressed adrenaline-induced arrhythmia and showed some antiarrhythmic effect on digitalis- and 48 hr coronary ligation-arrhythmias. These results indicate that SD-3212 has antiarrhythmic effects common among class IV antiarrhythmic drugs and also has additional efficacy common among class I antiarrhythmic drugs, thus when considering the level of experimental arrhythmias it somewhat resembles propafenone. It may therefore become a clinically useful antiarrhythmic drug among typical class I or class IV antiarrhythmic drugs.