[Diagnosis of diffuse myocardial changes in ischemic heart disease using orthogonal ECG leads].

In 100 patients with chronic ischaemic heart disease and diffuse changes in the myocardium the data of 12 common ECG leads indicated that the corrected orthogonal leads according to Mac Fee--Parungao and Frank reflect these changes in all cases. The severity of the diffuse changes reflected in the deviations of the ST segment and the T-wave in the orthogonal leads corresponds to that reflected in the 12 common leads. A mathematical analysis of the waves of the QRS complex in the X, Y and Z leads indicates a growth of the left ventricular potentials with the development of diffuse myocardial changes. The mentioned systems of orthogonal leads can be recommended for wide employment for the diagnosis of diffuse changes in the myocardium in ischaemic heart disease.