Effects of individual cardiac nerve stimulation on XXXX .

@entity1169 @entity235 @entity713 @entity2224 @entity3897 @entity299 @entity8108 @entity943
This study investigated the effects of individual @entity235 cardiac nerve stimulation on atrioventricular conductions as measured by His bundle electrograms. A-H and @entity8108 -V intervals were measured before and during stimulation of each nerve in paced hearts (200 beats/min) and before and after blocking doses of either @entity3897 or @entity1169 . Increases in A-H or H-V intervals were evidence of parasympathetic innervation; decreases in intervals were evidence of sympathetic innervation. Separation by autonomic composition produced 3 categories: sympathetic, parasympathetic, and mixed input to the @entity713 . The sympathetic nerves were the left and right ansae subclavia, the ventrolateral cardiac nerve, and the right stellate cardiac nerve. The parasympathetic nerve was the right thoracic vagus, and the mixed nerves were the left thoracic vagus, and the innominate, ventromedial, craniovagal, caudovagal, and right recurrent @entity299 . The @entity299 eliciting a major response were the left and right ansae subclavia, the ventrolateral, right recurrent, @entity299 , and the left and right thoracic vagi. In theory, the nerves of the right side, because of their innervation of both sinoatrial and atrioventricular nodes, may be expected to elicit a balanced heart rate- @entity713 response when stimulated, thus matching @entity2224 . On the other hand, stimulation of the ventrolateral cardiac nerve regularly produces @entity943 , due to increased automaticity at the @entity713 . Production of such @entity943 indicates the possible implication of imbalanced autonomic activity in arrhythmogenesis. Three @entity299 produced little or no effect on @entity713 . These were the innominate, ventromedial, and @entity299 . Because of its limited distribution and marked sinus rate effects, the right stellate cardiac nerve can be considered almost a purely positive chronotropic nerve. Its possible role in heart rate- @entity713 mismatching has not been delineated but, because of its nearly exclusive action at the sinoatrial node, may be of considerable importance.
