Arrhythmias Produced by Cardiac Nervous Stimulation.

To investigate the effects of cardiac nerves on the cardiac ectopic impulse formation, electrical stimulation of vagus and cardiac sympathetic was performed on the dog. It has been known that there are some discrepancies in the cardiac responses according to the side of the stimulated nerve. The right vagus and sympathetic have been said to send the fibers mainly around the S-A node, while the left to distribute to the A-V node. Our experiments, confirming the results of previous workers, proved that the stimulation of sympathetic potentiated the ectopic pacemaker in the atrium, the ventricle and particularly in the A-V node. The nodal tachycardia induced by sympathetic stimulation was of specific type, the mechanism of which was analyzed by means of atrial electrographic recording.