The effect of stimulation of the stellate ganglion on excitability of the heart.

Stimulation of the stellate ganglion leads to a shortening of the effective refractory period of the heart, while the electrical systole duration decreases in normal heart condition only secondarily in consequence of the increase in heart rate. In myocardial focal ischaemia stellate ganglion stimulation leads to an increase in the electrical systole time, the refractory period of the heart significantly shortens and the repolarization of the heart becomes inhomogenous. Consequently, the arrhythmogenic effect of a sympathetic excitation manifests itself mainly in myocardial ischaemia.