Role of myelinated and unmyelinated fibers of the vagus nerve in the development of ischemic fibrillation of the heart]

The effect of nn. vagi on ischemic heart arrhythmia was studied in acute experiments on cats. It was shown that thick myelinated fibers do not significantly alter the rate of onset of such arrhythmias. On the contrary, where the nn. vagi were cooled to 0 degree C, which entrained the block of non-myelinated fibers as well, the rate of ischemic heart arrhythmias (including heart fibrillation) drastically increased.