Serum neopterin and complex stenosis morphology in patients with unstable angina

OBJECTIVES We sought to assess the relation between serum neopterin concent ration and complex coronary artery stenosis in patients with unstable angin a. BACKGROUND Monocyte activation is associated. with acute atheromatous plaqu e disruption and acute coronary syndromes. Angiographically demonstrated co mplex coronary stenosis is often an expression of plaque disruption. Increa sed serum concentration of neopterin, a pterydine derivative secreted by ma crophages after stimulation by interferon-gamma, has been observed in patie nts with acute coronary syndromes as compared with control subjects and pat ients with stable angina pectoris. METHODS We studied 50 patients with unstable angina (32 men) who underwent coronary angiography after hospital admission. All coronary stenoses with g reater than or equal to 30% diameter reduction were assessed and classified as "complex" (irregular or scalloped borders, ulceration or filling defect s suggesting thrombi) or "smooth" (absence of complex features). Serum neop terin levels were assessed within 24 h of hospital admission using a commer cially available immunoassay (enzyme-linked immunosorbent assay kit, IBL, H amburg, Germany). RESULTS Thirty-nine patients were classified in Braunwald class IIIb, four in class IIb and seven in class Ib. The number of complex lesions per patie nt was 2.6 +/- 1.8 (mean SD). The mean neopterin concentration was 7.76 +/- 3.62 nmol/liter. A significant correlation was observed between neopterin serum concentration and the presence of complex coronary stenoses (r = 0.35 , p = 0.015). Multiple regression analysis showed that serum neopterin (p < 0.0001) was independently associated with the number of complex lesions. O ther variables associated with complex lesions were the number of vessels w ith greater than or equal to 75% stenosis (p < 0.0001), plasma creatinine ( p = 0.003), triglycerides (p = 0.014) and a history of unstable angina (p = 0.032). CONCLUSIONS Serum neopterin concentration is associated with the presence o f angiographically demonstrated complex lesions in patients with unstable a ngina and may represent a marker of coronary disease activity, (C) 2000 by the American College of Cardiology.