Relation between the location of coronary occlusion and the occurrence of shock in acute myocardial infarction. Circulation 31: 646

T HE mortality rate of shock associated with acute myocardial infarction re-mains high despite a variety of therapeutic approaches. ' The relative importance of re-duced cardiac output and reflex factors in the pathogenesis of this grave condition requires clarification if more satisfactory therapeutic measures are to be developed. " 2 Support for a reflex mechanism may be found in experimental coronary artery em-bolization in dogs.3 Microspheres that lodged in the right angle branches of the main stem coronary arteries produced shock, whereas larger or smaller emboli did not. These ob-servations, supported by hemodynamic data, suggested a reflex mechanism with receptors in the right angle branches, which interfered with an adequate compensatory rise in pe-ripheral resistance. The reflex hypothesis has not been verified in man, however. Hemodynamic data or angiographic studies are sparse because of the hazard in performing these studies on precariously ill patients. The present study, utilizing postmortem coronary angiograms, correlates the location of coronary artery occlusions and the occurrence of shock in acute myocardial infarction. Method More than 500 postmortem examinations of pa-tients who died of acute myocardial infarction at the Beth Israel Hospital between 1938 and 1955 were reviewed. All had been studied by the cor-onary injection and dissection technic of Schle