[Prognostic analysis of different endovascular revascularization techniques for below-the-ankle arteries in patients with chronic limb-threatening ischemia].

Objective: To analyze and compare the prognosis of different below-the-ankle artery revascularization techniques in patients with chronic limb-threatening ischemia due to atherosclerotic occlusive disease of the lower extremities, providing evidence for clinical decision-making. Methods: This is a retrospective cohort study. The clinical data of 117 patients with Rutherford category 4 to 6 lower extremity atherosclerotic occlusive disease who underwent endovascular intervention at Department of Peripheral Vascular Diseases, Xiyuan Hospital, China Academy of Chinese Medical Sciences between January 2023 and December 2024 were retrospectively analyzed. There were 84 males and 33 females, aged (69.2±8.0) years (range: 53 to 87 years). Based on below-the-ankle artery revascularization technique, patients were divided into plain old balloon angioplasty (POBA) group (n=52), drug-coated balloon (DCB) group (n=33), constrained balloonangioplasty group (n=26), and debulking combined with antiproliferative therapy (DAART) group (n=6). The post-procedural ankle-brachial index (ABI) improvement, 6-month clinical-driven target lesion revascularization (CD-TLR)-free rate, 6-month clinical efficacy rate and wound healing rate were collected. The comparison of data among the plain old balloon angioplasty group, drug-coated balloon group, and constrained balloon group was conducted using independent sample t-test, one-way analysis of variance, chi square test, and Kruskal Wallis H test. Due to the small number of cases in the debulking combined with antiproliferative therapy group, only data description is provided. Results: The CD-TLR-free rate of the 117 patients was 85.5% (100/117), and the 6-month clinical efficacy rate was 72.6% (85/117). Only one patient in the POBA group underwent above-the-ankle amputation, and there were no deaths. The ABI of the patients in the POBA group, DCB group, and constrained balloon group increased significantly on the first day after surgery compared with that before surgery, and the difference in the increase of ABI was not statistically significant (P>0.05). There was no statistically significant difference in the 6-month CD-TLR freedom rate and treatment effectiveness rate among the three groups (P>0.05). Among patients free from revascularization at 6 months, the increase in ABI at 6 months after surgery in the POBA group was 0.18±0.13, in the DCB group was 0.30±0.08, and in the constrained balloon group was 0.32±0.24, and the difference was statistically significant (F=10.955, P<0.01). Among the patients with Rutherford grade 5 to 6, the wound healing rate in the DCB group was 82.8% (24/29), which was higher than that in the POBA group (56.5%, 26/46) (χ2=5.509, P=0.019), and there was no statistically significant difference compared with the constrained balloon group (61.9%, 13/21) (χ2=2.753, P=0.097). The ulcer healing time in the DCB group was (9.0±0.5) weeks, which was shorter than that in the POBA group (13.8±8.9) weeks (t=2.636, P=0.011) and the constrained balloon group (10.4±1.4) weeks (t=4.446, P<0.01). In the DAART group, the ABI increased by 0.59±0.11 (range: 0.44 to 0.72) on the first day after surgery compared with that before surgery, and by 0.47±0.09 (range: 0.34 to 0.57) at 6 months after surgery. All patients in the DAART group were effectively treated at 6 months after surgery, were CD-TLR-free, and had healed ulcers, with a healing time of (6.6±1.9) weeks (range: 1 to 12 weeks). Conclusions: Below-the-ankle artery revascularization may provide a favorable short-term prognosis for chronic limb-threatening ischemia patients. Especially for patients with Rutherford classification 5 to 6, DCB demonstrated higher wound healing rates and shorter healing times within 6 months post-procedure, which may have certain clinical advantages.