Lipoprotein(a) is related to the extent of lesions in the coronary vasculature and to unstable coronary syndromes

Background: Lp(a) is a highly atherogenic particle with a prothrombotic eff ect. Until now its relation to the extent and severity of the atheromatic l esions had not been established by standard procedures. Hypothesis: This study examined the correlation of Lp(a) to the extent and severity of coronary artery disease (CAD) and its relation to unstable clin ical events (not including sudden death). Methods: In 202 patients undergoing coronary angiography, plasma lipids wer e measured with the usual procedures and Lp(a) with the enzyme-linked immun osorbent assay. The extent of CAD was expressed in the number of diseased v essels and its severity in terms of the severity coefficient and the obstru ction coefficient. Results: A very strong relationship between LP(a) and the number of disease d vessels (p = 0.0007) signifying diffuse atherosclerosis, but no relation with the severity of the lesions, was found. However, it was the only lipid that correlated significantly with the number of totally occluded vessels (p = 0.0003). The thrombogenic ability of Lp(a) was manifested by increased incidence of myocardial infarction and unstable angina episodes in patient s with elevated Lp(a) (p = 0.0157). Conclusion: Elevated Lp(a) predisposes to the extent of CAD and total occlu sions but not to the severity of lesions. Patients with increased Lp(a) lev els and unstable angina are at increased danger of suffering: myocardial in farction. Thus, Lp(a) may predispose to plaque destabilization and thrombos is of noncritical lesions.