Study on the Relation between the Electrocardiographic Change and the Histological Change in the Experimental Myocarditis

Abstract

(II) Experimental Myocarditis The exprimental study of allergic myocarditis has been made by many scholars since olden times. But it was very difficult that allergic changes were produced in the disirable organ freely and locally. As the mechanism of allergy was made clear by Professor Maekawa's allergy theory and by a series of experiments on allergy in his laboratory, allergic inflamation has been able to be caused freely in the heart. Already a few reports on the relation between electrocardiographic changes in allergic myocarditis and its histological changes have been described. The reports chiefly stated that, in spite of remarkable histological changes, the electrocardiographic changes were very slight and the mutual-relationship was not clear. F or the purpose of knowing whether the electrocardisgraphic changes were caused by the myocarditis or not, the course of the disease was investigated with the limb-lead electracardiogram; moreover, to examine them in detail, the chest lead electrocardiogram with photographic method that was already reported was taken. Thus the relation between the histological change and the electrocardiographic change was studied.Method : 1) Antigens : By means of Kitasawa's method, cephalin and lecithin were extracted from ox myocardium. The white of an egg (2 cc/kg) which was diluted 50 % by physiological salt solution, or ox serum (2 cc/kg) were added to cephalin (2 mg/a rabbit) or lecithin (8.5 mg/a rabbit) and they were mixed fully. After they were let alone a room for an hour they were used.2) Rabbits were sensitized by intravenous injection of the above mentioned antigens for 3 days (once a day) and were reinjected by the same antigen for 3 days (once a day) 3 weeks later.At the 7th day after reinjection, rabbits were killed.3) Throughout this experiment, all rabbits were observed electrocardiographically and histological surveys were compared with electrocardiographic findings.4) Some rabbits were killed halfway and histological surveys were compared with electrocardiographic findings.Results and Conclusion : 1) When the substance, which a mixture of 50 % raw white physiological salt solution with ox cephalin or lecithin (the antigen) was used, the histological changes in heart were generally interstitial, sligth perivascular infiltration and more remarkable in the right ventricle than in the left ventricle.When the mixture of ox serum with cephalin or lecithin, was used : chiefly a remarkable perivascular myocarditis; moreover, interstitial myocarditis and endocarditis were found.In either case, the longer the time after reinjection, passes by the more marked histological cnanges were found.But the others before reinjection and after sensitization showed slight changes. When lecthin was used, no matter what the protein was, the histological changes in their heart were much slighter than in that case of cephalin.2) Generally, the electrocardiographic changes were weaker relative to the histological changes.When the histolofical changes extended to the pericardium, electrocardiographic findings were marked. Alterations of ST segment and T wave (monophasic ST, T) were registered both in the limb lead and in the chest lead.In other cases, in general, their findings were the elevation or depression of ST segment and increased, decreased, low or inverted T, etc.3) The relationship was as follows between electrocardiograms of rabbits and their histological findings of their heart.Namely, in 4 cases which were destroyed pericardium and myocardium among 19 cases of definite histological changes, the elevation of ST segment in lead I and lead II, the depression of Segmen in lead III, and the monophasic STCF3, CF4 segment and TCF3, CF4 wave in the chest lead were noted. They showed just the same electrocardiographic changes that were noted in man. [the rest omitted]