Studies on the Relationship between the Initial Deflection of Electrocardiogram and the Histologic Fndings following the Experimental Myocardial Infarction (III).

Abstract

In experimental myocardial infarction was observed the relationship between the initial deflection of ecg and histologioc findings. 1. Low voltage (under 0.5mV in all leads) was observed in cases, which myocardial damage were in the highst degree. 2. In the other cases, the changes of the initial deflection were variously. In the cases, which had aneurysma at the ventricular apex, the initial complexes deflected downwards, and not upwards in lead II and III. For detailed analysis of initial deflections were calculated the largest potentials (Φ_A) and their directions (θ_R) by means of orthogonal isoscale triangle coordinate (Maekawa). Results were as following. 3. In 5 cases (A-group), which Φ_A increased, was the extension of myocardial damage relatively localized and superficially. Φ_A increased immediately after the operation for the almost cases. The change of θ_R showed undetermined results compare with that before operation. 4. In 9 cases (B-group), which Φ_A decreased, the extension of myocardial damage excelled the apparent width. Histologic change was diffuse and reached to deep and degree of degeneration of myocardium was higher. Φ_A decreased immediately after the operation for the most cases. θ_R deviated to the right. 5. In the 6 cases (C-group), which Φ_A showed no remarkable change, was myocardial damage the same as A & B groups. The change of Φ_A in the cource of experiment and rotation of θ_R were variously in each cases. 6. In all cases, ecg were monophasic or biphasic in the sometime during the experiment. These results of the experiment showed that electrical change of the heart is produced by myocardium itself and its electrical potentials are representated as vectors directed from endcardium to epicardium according to excitement of myocardium. And so, ecg by limb lead represents rotation of a vector, which is resulted from those vectors. These facts give a experimental evidence to the "Chain-doublets" theory (Maekawa), that supposes the causality among the three physical phenomena, namely electricity, contraction and double refraction of myocardium.