[Coronary insufficiency caused by atherosclerosis. Current pathogenic concepts, clinical, angio-anatomic correlations and therapeutic deductions].

The multiplicity of clinical expressions of coronary artery failure results from the interaction between three processes which varies from one patient to another and from one time to another in a given patient. The three processes involved are: atheromatous coronary stenosis, arterial spasm and the development of a fibrino-thrombocytic thrombus. In stable angina pectoris, atheromatous narrowing, with smooth, regular outlines, no endothelial injury and little likelihood of complication by thrombosis predominates. In contrast, labile angina and myocardial infarction give rise to the same lesions: usually irregular stenoses, with a narrow neck and irregular outline. They correspond histologically to the rupture of an atheroma plaque, frequently complicated by the appearance in situ of a clot. In the authors' experience, complete arterial occlusion ensues in three out of four cases. The rate at which aggravation progresses and the variable degree of collateral circulation explains why a whole range of intermediate clinical expressions are possible, ranging from labile angina to sudden death of ischemic origin, and including various forms of infarction (both with and without the Q wave). Healing of these lesions may also be observed, usually resulting in progression of the coronary stenosis and sometimes of modification of left ventricular function of variable duration (myocardial stunning or hibernation). The importance of thrombotic phenomena in triggering the most serious forms of coronary artery failure (labile angina and myocardial infarction) provides a more precise identification of the place of thrombolytic treatment. In addition, it appears that there is no point in emergency revascularization of the ischemic myocardium. However, despite recent clinical progress, coronary artery disease remains a worrying illness which calls for primary prevention measures. Such measures must be undertaken as soon as possible if they are to be effective.