Evidence for priming and activation of neutrophils early after coronary angioplasty.

OBJECTIVES

Percutaneous transluminal coronary angioplasty (PTCA) induces deep arterial wall injury and transient ischaemia. The aim of this study was to demonstrate that PTCA could result in priming or activation of the neutrophils and the complement system.

METHODS

Blood was drawn from the coronary sinus before and immediately after PTCA in 7 patients and before and immediately after coronary angiography in 7 patients (to ensure that the changes observed after PTCA were not solely related to the angiographic procedure). Neutrophil priming was assessed ex vivo by whole blood chemiluminescence stimulated in vitro by formyl-methionyl-leucyl-phenylalanine, phorbol myristate and opsonized zymosan. Neutrophil activation was assessed by measurement of plasma lactoferrin.

RESULTS

Whole blood chemiluminescence increased after PTCA, regardless of the stimulus used, while it did not after arteriography. After PTCA, lactoferrin increased 2-fold (p < 0.02) whereas after arteriography a non-significant increase was observed. Neutrophil count and adherence properties were not modified by either PTCA or arteriography. Total haemolytic complement (CH50), C3, C4 and B factor decreased slightly (7 to 16%) after both PTCA and arteriography.

CONCLUSIONS

Early after PTCA, the neutrophil oxidative response, assessed by stimulated whole blood chemiluminescence, increased, suggesting a "priming" effect of PTCA on neutrophils. In addition, plasma lactoferrin levels increased, indicating neutrophil activation. Finally, there was a mild global activation of the complement system, most likely related to the contrast agent, and which may play a role in the "priming" process. Neutrophil priming and activation may participate in several phenomena occurring after angioplasty such as enhanced vasoconstriction and post-ischaemic myocardial dysfunction. In addition, it may participate in triggering local inflammatory processes.