Altered activity of leukocytes derived from circulating blood immediately after revascularization in peripheral artery disease

Endovascular treatment (EVT) is an effective therapeutic option for patients with peripheral artery disease (PAD). However, EVT is associated with inflammatory adverse effects, and the systemic oxidative status after EVT remains unclear. In this pilot study, we compared the activity of leukocytes derived from circulating blood before and immediately after (within 1 h of) EVT in 30 cases with PAD. The ankle-brachial index (ABI) improved immediately after EVT (p < 0.001), suggesting successful revascularization. The levels of leukocyte-produced superoxide radicals (O₂^•−) increased (p < 0.05), those of hypochlorite ions (OCl⁻) remained unchanged, and the OCl⁻/O₂^•− levels reduced (p < 0.001) immediately after EVT. We observed two subtypes of alterations in leukocyte activity immediately after EVT: type A exhibiting increased levels of both O₂^•− and OCl⁻, and type B showing increased O₂^•− levels, while relatively small changes in OCl⁻ levels. In addition, the interleukin-6 levels increased (p < 0.05) immediately after EVT. Moreover, EVT increased the leukocyte count (p < 0.001) and dynamically changed the balance of leukocyte components, with a notable increase in the neutrophil percentage. These findings and results of our correlation analyses imply that inflammatory response and/or ischemia–reperfusion potentially alters O₂^•−production by leukocytes. This study contributes to the understanding of the pathophysiology of EVT-associated systemic oxidative events, which includes vascular inflammation and ischemia–reperfusion injury. The findings can support further development of diagnostic and therapeutic strategies for the health conditions after EVT.