Arrhythmias induced by local cardiac nerve stimulation.

ARMOUR, ,J. A., G. R. HAGEMAN, AND W. C. RANDALL. Arrythmias induced by local cardiac nerve stimulation. Am. J. Physiol. 223(5) : 10684075. 1972.-Electrical and mechanical activity were recorded from multiple regions of the canine heart during electrical stimulation of distal portions of individual cardiac nerves. Functional responses included generalized augmentation in contractile force, together with sinus or supraventricular tachycardia when the stimulus was applied to the stellate ganglion or to portions of the left sympathetics rostra1 to their projection onto the surface of the heart. Alterations in contractile force and the development of tachyarrhythmic states became more localized as the ventrolateral cervical cardiac nerve was stimulated more distally. Mechanical alternans accompanied progressive acceleration in heart rate, but was generated to varying degrees within highly localized portions of the cardiac musculature. Excitation of the ventrolateral nerve at the level of the superior pulmonary vein elicited marked tachycardia with a supraventricular pacemaker. Stimulation of the same nerve at a point just caudal to the inferior pulmonary vein where it projects onto the left ventricle induced both atria1 and ventricular tachycardias, each at a different rate. Effective reserpinization or local procainization eliminated the ability to elicit such tachyarrhythmias.