[Tobacco: an atherogenic, thrombogenic or spasmogenic factor?].

Smoking is one of the major causes of morbidity and mortality in the developed world. The main cause of death related to smoking is myocardial infarction. Smoking not only accelerates the process of atherosclerosis but also predisposes to acute complications, early in atheromatous disease, and which may be fatal. Complex effects implicated in cardiac complications include hypercoagulability, increased cardiac work, reduced oxygen transport and delivery, catecholamine liberation, and coronary vasoconstriction. These effects of tobacco which increase myocardial oxygen consumption whilst decreasing oxygen delivery, participate in precipitating acute cardiovascular complications. They are mainly related to the actions of nicotine and carbon monoxide. The atherogencity of smoking seems to be related to the many adverse effects on endothelial function, vascular tone, haemostasis, lipid profile and inflammatory cells. The action of oxidising and toxic glycation products, which are present in cigarette smoke and active on the vascular wall, are the principal mediators.