PATHOLOGY OF ACUTE ISCHEMIC MYOCARDIUM SPECIAL REFERENCES TO (I) EVALUATION OF MORPHOLOGICAL METHODS FOR DETECTION OF EARLY MYOCARDIAL INFARCTS, AND (II) LIPID METABOLISM IN INFARCTED MYOCARDIUM

Abstract

Morphological changes of early myocardial infarction within 24 h after the onset of the acute attack were described along with a review of the literature. For detecting very early infarcts, enzymatic histochemistry is the most reliable method. Lipid metabolism in the infarcted myocardium of dogs was studied morphologically and biochemically. Up to 3 h after the coronary ligation the tissue lipids accumulated in the necrotic areas with a rise in triglycerides. After 6 h the lipids decreased and were lost from the necrotic tissue. The surrounding living cells accumulated neutral lipids. Serum free fatty acids [FFA] were elevated in the coronary sinus blood 6 h after ligation. Linolic acid was present in coronary venous blood after 6 h and in normal myocardial phospholipids. Another factor in addition to catecholamine activity may elevate serum FFA in acute myocardial infarction.