PLASMA LEUKOCYTE ELASTASE CONCENTRATION IN ANGIOGRAPHICALLY DIAGNOSEDCORONARY-ARTERY DISEASE

Objective: To evaluate the clinical usefulness of leukocyte elastase d etermination in the diagnosis of coronary artery disease (CAD). Backgr ound: Recent research has shown the important role of elastase, a prot eolytic enzyme released by neutrophils, in the pathogenesis of CAD. Me thods: 141 patients underwent coronary angiography during investigatio n of chest pain and/or heart valve disease. Ninety-six had coronary le sions and 45 non-stenotic coronaries. The patients were characterized as regards presence or absence of angina (stable or unstable), family history of CAD, smoking, diabetes mellitus, hypertension, leukocyte ,c ounts, and plasma lipid and elastase concentrations. Among CAD-group p atients, those with simple atheromatous plaques were distinguished fro m those with complex plaques. Results: Elastase concentrations were gr eater in the CAD group than in the non-CAD group (49.7+/-2.8 mu g.l(-1 ); as against 29.5+/-2.2 mu g.l(-1); P<0.001), and greater among compl ex-plaque CAD patients than among simple-plaque CAD patients (65.2+/-5 .3 mu g.l(-1) as against 38.6+/-1.9 mu g.l(-1), P<0.001). Logistic reg ression analysis showed ja) that the risk of CAD varied with elastase concentration, angina status, age and sex, increasing by 11% for every 1 mu g.l(-1) increase in elastase concentration; and (b) that among C AD patients the risk of complex plaques was greatest for those with un stable angina and high elastase concentration, increasing by 6% for ev ery 1 mu g.l(-1) increase in elastase concentration. Conclusions: Peri pheral blood leukocyte elastase concentration is a sensitive diagnosti c marker of CAD. High values suggest the presence of complex atheromat ous plaques.