Beyond lipids — the role of the endothelium in coronary artery disease

The beneficial effects of statin therapy in patients with coronary heart disease (CHD) outweigh those expected from simply lowering low-density lipoprotein (LDL) cholesterol, and occur too early in treatment to be due to this mechanism alone. Endothelial dysfunction is present in patients with atherosclerosis, even in the early stages before plaque formation, making it a useful marker for early cardiovascular disease. Statins reduce endothelial dysfunction, which improves myocardial perfusion and angina pectoris. In recent studies with statin therapy, the improvement in endothelial function has been attributed, in part, to an increased production of nitric oxide (NO), a key vasodilator, from the endothelium. These studies have shown that pravastatin and simvastatin improve endothelial function in the short term, with variable effects on vasodilation, which may be due to differences in their effects on NO production. Whether these differences between the statins may result in long-term differences in net clinical benefit has to be awaited.