Observations on the Effect of Vagus

Our present knowledge of the nervous regulation of the human heart is dependent upon two sources of information. One is the direct observation of the effect of stimulation of the nerves in experimental animals with the assumption that the nerves act similarly in man; the second is from clinical observation. A method has been devised by which the direct effect of stimulation of the vagus and sympathetic nerves can be studied in the human heart. Observations were made on eight subjects, three of whom met death suddenly. In these the bodies were obtained 10 minutes postmortem. Five others died of a chronic illness, one of aplastic anemia, one of pulmonary tuberculosis, and the other three of malignancy. Their bodies were obtained within 20 minutes after death. The effect of drugs on the beating human heart was studied on a considerable group of other cases, some of which have been previously reported (1).