[Smoking and coronary heart disease]

Smoking increases the risk of developing coronary heart disease in men and women.

Several epidemiological studies have demonstrated an almost linear relationship between smoking and coronary heart mortality and morbidity, the risk being more than twofold and most pronounced in younger individuals.

Smokers are younger than nonsmokers when they suffer their first myocardial infarction, more of them are males, and they experience more frequently posterior infarcts. They are likely to develop right coronary occlusions, the lesions being rather thrombogenic than atherosclerotic. This phenomenon may partly be related to the specific flow pattern in the right coronary artery. Passive smoking is harmful. Quitting smoking in patients and in healthy individuals reduces the risk markedly within a short period of time.

Smoking causes vasoconstriction of coronary arteries, and endothelial function as well as fibrinolysis is impaired while platelets are activated. A human ex-vivo experimental model has shown that the thrombus volume was increased twofold in blood from smokers at shear forces that are found in moderately stenosed coronary arteries. In addition, smokers are insulin-resistant and at increased risk of developing diabetes mellitus.