Electrophysiologic Effects of Isoproterenol and Beta Blocking Agents in Awake Dogs
نویسنده
چکیده
• The effects of changes in sympathetic activity on electrophysiologic properties of the heart are not clearly defined. In a previous report Wallace and Sarnoff demonstrated that stimulation of cardiac branches of the stellate ganglion enhanced conduction through the A-V node, but had no effect on conduction in Purkinje tissue or the sequence of ventricular activation. Their study was performed on anesthetized dogs in which cardiac sympathetic activity might have been excessive; since it concerned only the effects of augmenting sympathetic discharge, it did not include observations over the full range of sympathetic influence.
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