Clinicopathological Studies on Myocardial Infarction : Correlation between Clinical Pictures and the Myocardial Destruction Quantitatively Estimated by Means of Point-Counting Method

It is surprising that little attention has been payed to the correlation between the clinical pictures and the extent and distribution of myocardial infarction (MI) confirmed at necropsy. The purpose of this study is to analyse the pathoanatomical basis of the following clinical manifestations in MI i e the duration of clinical course, complications following initial infarction (angina pectoris, acute coronary insufficiency and congestive heart failure (CHF)) and mode of death (cardiogenic shock (CS), CHF and intractable arrhythmia). Materials and Methods: Twenty consecutive cases with MI (17 males and 3 females) were selected. All the patients were hospitalized in the Cardiovascular Institute Hospital and died at least after 12 hrs following onset of the last MI, either without clinical evidence of severe papillary muscle dysfuction, cardiac rupture or ventricular septal perforation. After formalin fixation each heart was cut into slices 5mm thick form the apex to the atrioventricular groove. Histological preparations (hematoxylin and eosin, and azan staining) were made in each slice, and the morphological classification of MI (acute or healed, massive or scattered and its localization) was made. By "point-counting" method the area of acute and healed MI of the three representative transverse cross-sections (apical, middle and basal one-third levels) were measured and expressed as percent values of acute, healed and total lesions in the whole myocardium. And also, the sum of the both was referred to percentage of total destruction of ischemic myocardium. The main coronary arteries and their branches were sectioned at 5mm interval along the epicardial course, and maximal degrees of obstruction were observed, and their mathematical average was regarded to represent the severity of coronary stenoses.