[The effectiveness of trapidil and trapidil derivatives on drug-induced heart arrhythmias in the rat and guinea pig].

Trapidil and some selected derivatives of trapidil were investigated in ouabain induced arrhythmia in guinea-pigs and in aconitine induced arrhythmia in rats. In both models trapidil exerted a marked antiarrhythmic effect. Investigations on ouabain induced arrhythmia showed that three derivatives were more effective than trapidil concerning the threshold for premature ventricular beats and flutter. One derivative only was able to decrease the sensitivity for fibrillation in the same order of magnitude as trapidil. On aconitine induced arrhythmia all derivatives of trapidil were less effective in elevating the threshold of arrhythmia than trapidil itself, but three derivatives showed antiarrhythmic properties.