Plasma leukocyte elastase concentration and coronary artery disease.

It has previously been shown that leukocyte elastase is involved in the pathogenesis of atherosclerosis. Few studies have addressed the relation between leukocyte elastase concentrations and coronary artery disease (CAD). The authors investigated (1) the clinical significance of leukocyte elastase determination in the diagnosis of CAD and (2) the relation between plasma leukocyte elastase concentration and lesion morphology. The study included 185 subjects (140 men, 45 women) who underwent coronary angiography during investigation of chest pain; 135 had coronary stenosis (Group I) and 50 had nonstenotic coronaries (Group II). Among Group I patients, those with simple atheromatous plaques were distinguished from those with complex plaques. Elastase concentrations in Group I were greater than in Group II (57.1 +/- 1.16 micrograms I[-1] vs 27.6 +/- 1.0 microgram, I[-1], P<0.001), and greater in complex plaque patients than in those with simple plaques (64.5 +/- 1.24 micrograms I[-1] vs 45.9 +/- 1.01 micrograms I[-1], P<0.001). Logistic regression analysis showed (1) that elastase concentration, age, and sex had independent value for prediction of CAD and (2) that among Group I patients, the risk of complex plaques was greatest for those with high elastase concentration. These results suggest that plasma leukocyte elastase concentration is a sensitive diagnostic marker of CAD and that high values of elastase may indicate the presence of complex atheromatous plaques.