Jul 1, 1975

Electrophysiologic effects of isoproterenol on cardiac conduction system in man

American Heart Journal
G VargasA N Damato


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.

  • References11
  • Citations37

Mentioned in this Paper

Structure of Purkinje Fibers
Left Bundle Branch of His
Sinus - General Anatomical Term
Refractory Period, Electrophysiological
Cardiac Catheterization Procedures
Atrial Fibrillation
Refractory Period
Cardiac Conduction System
Artificial Cardiac Pacemaker

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