Electrophysiologic effects of isoproterenol on cardiac conduction system in man.
The effects of isoproternol (ISOP) on the functional properties of the A-V conduction system were studied in 16 patients using His-bundle recordings and the atrial extrastimulus technique. In all patients, ISOP at an infusion rate of 1 mcg. per minute resulted in sinus acceleration and enhancement of A-V nodal conduction, but had no effect on His-Purkinje conduction time. ISOP significantly decreased both functional and effective refractory periods of the A-V node. The relative refractory period of the His-Purkinje system decreased by a small amount in five patients in whom the parameter could be compared before and after the drug.
D000328:Adult; D000368:Aged; D001283:Atrioventricular Node / Q000187:drug effects; D002036:Bundle of His / Q000187:drug effects; D006328:Cardiac Catheterization; D004558:Electric Stimulation; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects*; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D011690:Purkinje Fibers / Q000187:drug effects; D012032:Refractory Period, Electrophysiological / Q000187:drug effects
D007545:Isoproterenol