Background   There are limited evidences regarding the clinical effect of percutaneous transluminal angioplasty (PTA) in the treatment of below-the-knee chronic total occlusion, and the key points of treatment remain unclear.

  Objective   To investigate the midterm clinical effect and key points of PTA in the treatment of below-the-knee chronic total occlusion.

  Methods   A retrospective analysis was performed for the clinical data about 18 patients with below-the-knee chronic total occlusion who were admitted to the department of peripheral vascular disease, Shenyang Second Hospital of Traditional Chinese Medicine from January 2019 to January 2020, and related data were analyzed, including the process of surgical treatment, clinical symptoms and signs before and after surgery, severity of ulcer and gangrene, auxiliary examination, and vascular patency.

  Results   Among the 18 patients, there were 10 male patients and 8 female patients, with a mean age of 65.5 ± 5.53 years, and all patients were followed up for 24 weeks after PTA. At 2 weeks after PTA treatment, 10 patients were cured, 5 had marked response, 2 had improvement, 1 had no change, and no patient had deterioration, with a response rate of 94.4%. After surgery, 15 patients achieved revascularization, an increase in skin temperature, and an improvement in ankle-brachial index, and the success rate of surgery was 83.3%. Nourishing vessels were established around the lesions for 2 patients, who had improved clinical symptoms. One patient experienced failure in revascularization and had no change in clinical symptoms, thus trans tibiofibular amputation was performed. Rutherford class and Wagner grade changed over time and decreased significantly after surgery (P＜0.05). Within 2-4 weeks after PTA, 2 patients achieved ulcer healing, and ulcers transformed into dry gangrene in 2 patients; within 4-8 weeks after PTA, 3 patients with clear amputation level underwent partial amputation of feet or toes (a second surgery was performed for 1 patient with dry gangrene) and achieved good incision healing and a reduction in amputation level. The limb salvage rate was 94.4%. The restenosis rate was 20% at 12 weeks after PTA, and secondary patency was obtained after PTA treatment again. At 12 and 24 weeks after surgery, the primary patency rate was both 80%, and the secondary patency rate was both 100%.

  Conclusion   PTA is a safe and effective method for the treatment of below-the-knee chronic total occlusion.