Abstract
The author studied the influence of infra-red rays upon the electrocardiogram of myocardiac weakness and obtained the following results. By the irradiation, the height of P wave increased, and that of R and T wave decreased, and these changes were greater than in the normal electrocardiogram. In about half cases, P〜Q interval was shortened by the irradiation like in the normal, and in other half cases, it was not shortened. Also the approach of the observed value of P〜Q and the calculated value of P〜Q, was more indistinct than in the normal. And 30 minutes after the irradiation, these changes restored almost to the values before the irradiation.
