Increased leukocyte activity as a predictor for flow-limiting coronary lesions in patients with angina pectoris

Myocardial ischemia initiates an acute inflammatory response, in which polymorphonuclear leukocytes (PMNs) are major participants. We investigated whether increased PMN activity in the peripheral blood is a marker for high-grade coronary artery stenosis in patients with angina pectoris. PMN activity was examined in 45 patients by measuring the luminol-dependent chemiluminescence (CL) response of the peripheral blood upon addition of phorbol myristate acetate (PMA). The CL of patients with angiographic filling delay was 1.6-fold higher than in patients without delay (480±54 vs. 302±33 counts/PMN, P<0.01). The CL of patients with a filling delay of the left anterior descending artery (LAD) was 1.7-fold higher than in patients without an LAD filling delay (537±79 vs. 317±27 counts/PMN, P<0.01). With the CL cut-off at 400 counts/PMN, the sensitivity and specificity for detecting an angiographic filling delay of the LAD were 69 and 75%, respectively. These data indicate that PMN activity in the peripheral blood is increased with the presence of a flow-limiting coronary lesion showing an angiographic filling delay. Measuring PMN activity may be a useful approach to assess indications for and timing of angiography and/or adjunctive invasive therapies in patients with angina pectoris.