Abstract
ECG and VCG diagnosis has still various difficulties. In order to overcome these difficulties, following studies were attempted : 1) Various combinations of height of the waves recorded by Frank's orthogonal leads were compared as index for left ventricular hypertrophy. RX/RY was most useful to differentiate LVH from normal and had larger positivity than some other criteria presented by various authors. On the one hand, RX+ SY + SZ was thought to be a better index for degree of LVH. 2) Differential curves of the second order of coronary T wave is considerably differed from that of usual negative T wave. Differences are also observed in the differential curve of the first order between the RS-T elevation in myocardial infarction and non-specific elevation. The differential curves are useful for objective recognition of shape of the waves. 3) Statistical diagnosis of disease by ECG findings was attempted by using Bayes' theorem without referring to other clinical data. Calculation with electronic computor showed fairly correct answers in various actual cases. Some of the results are indicated.
