Efficacy and Safety of Cold Atmospheric Plasma Combined With Endovascular Intervention for Diabetic Foot Ulcers With Lower Extremity Arterial Occlusion: A Randomized, Double-Blind, Placebo-Controlled Trial

CAP-activated gas treatment developed by Xi'an Jiaotong University (Chinese patent No. ZL202110209052.X); administered once daily for 10 days, 25 minutes per session.

Identical equipment without plasma activation; simulates treatment environment (sound, airflow) for participant blinding.

Balloon angioplasty is performed on infrapopliteal arteries with significant stenosis or occlusion. Technical success is defined as \<30% residual stenosis, confirmed intraoperatively by digital subtraction angiography (DSA). Only patients with successful revascularisation are eligible for randomisation.

All participants will receive diabetic foot ulcer (DFU) care according to current international and Chinese clinical guidelines