[Study of the electrophysiological properties of bretylium tosylate in man].
The electrophysiological changes induced by bretylium tosylate have been studied in 22 patients during the 45 minutes following the intra-atrial injection of the drug at the dose of 5 mg/kg. The potential in the bundle of His was measured, and the stimulus-test method used to determine the refractory period. The results were subjected to Student's test. The sinus rate increased after bretylium. The A-V nodal conduction time (A-H interval) and infra hisian conduction time (HV interval), evaluated at the same imposed frequency, were not affected. The functional refractory period of the A-Vnode was decreased. The relative refractory period of the His-Purkinje system was increased. Finally, the right auricle showed an increase in its effective refractory period, while that of the ventricle remained unchanged. This study suggests that the electrophysiological effects of bretylium are due both to direct action at the cellular level and to sympathetic activity.
D000200:Action Potentials / Q000187:drug effects; D000328:Adult; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology; D001949:Bretylium Compounds / Q000494:pharmacology*; D001950:Bretylium Tosylate / Q000494:pharmacology*; D002986:Clinical Trials as Topic; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D013223:Statistics as Topic
D000889:Anti-Arrhythmia Agents; D001949:Bretylium Compounds; D001950:Bretylium Tosylate
Etude des propriétés électrophysiologiques du tosylate de brétylium chez l'homme