Trans-vessel gradient of myeloperoxidase in coronary artery disease

Background Coronary artery disease (CAD) may reflect generalized inflammation. We evaluated leucocyte activation in subjects with and without CAD in different vascular compartments. Materials and Methods Patients were divided in two groups; subjects without CAD (controls; n = 25) and with stable CAD (n = 52) based on coronary angiography. After blood sampling from vessels, cardiovascular risk factors and leucocyte activation markers CD11b, CD66b and cytoplasmatic myeloperoxidase (MPO) were determined by flow cytometry. Results Myeloperoxidase (MPO) was higher in patients with CAD at all sites compared with controls (188 +/- 7 vs. 210 +/- 12 au for venous (P < 0.05), 178 +/- 7 vs. 212 +/- 12 au for femoral artery (P = 0.08), 166 +/- 7 vs. 195 +/- 12 au for abdominal artery (P < 0.05), 166 +/- 6 vs. 189 +/- 14 au for left coronary (P = 0.08) and 163 +/- 6 vs. 193 +/- 12 au for the right coronary artery (P < 0.05)). Other markers did not differ between the groups. A gradient of inflammation from peripheral vessels to the coronaries was found by differences in MPO in both groups; from 210 perpendicular to 12au in the venous compartments towards 189 perpendicular to 14 and 193 perpendicular to 12au, in the left and right coronaries, respectively, for the controls (P = 0.001), and from 188 +/- 7 au in the venous compartment towards 166 +/- 6 and 163 +/- 6 au in the left and right coronaries, respectively, for the patients (P = 0.007). Other leucocyte activation markers did not show such a gradient. Conclusions There is a generalized inflammatory neutrophil gradient for MPO from peripheral vessels towards the coronaries in both patients with CAD and controls. However, patients with CAD show a higher degree of inflammation, mostly in the coronaries. These data strengthen the role of activated neutrophils in CAD.