Reproduction of twelve routinely used ECG leads from three orthogonal ones

The paper presents the results of the reproduction of routinely used leads from three corrected orthogonal leads in the system SVEC III modified by L. I. Titomir. Simultaneously with routine and reproduced leads, the differences among them were recorded at every instant of time. In the reproduction for each proband and each lead an individual selection of vector parameters for the given lead was performed. This method was applied in the examination of 150 probands, including 121 patients with myocardial infarction (MI) and 29 healthy subjects. A comparison of routine with reproduced leads showed that in both healthy subjects and patients with MI the limb leads were well reproducible; reproduction of thoracic leads was poorer, especially in patients with MI. Greatest reproduction errors occurred in leads V2 and V3. In 12.5% of patients with anterior-wall infarct, the diagnostically highly important indicators, pathological Q and informative T waves, were not reproduced. The authors assume that in isolated anterior-wall MI, which manifests itself solely in leads V2 and V3, diagnostic errors occur when only three corrected orthogonal leads are used.