Predictors of Technical Success in Retrograde Pedal Interventions for Chronic Limb-Threatening Ischemia: A...

To identify predictors of technical success in retrograde pedal interventions for chronic limb-threatening ischemia and develop a morphologic scoring system.

In this retrospective, single-center study, 354 retrograde pedal interventions performed in 296 patients with chronic limb-threatening ischemia between January 2023 and July 2025 were analyzed. Lesion characteristics including calcification severity, cap morphology, lesion length, and distal outflow were evaluated. Predictors of technical success were identified using univariable and multivariable logistic regression analyses with patient-cluster robust standard errors. A morphologic score was developed based on independent predictors. Model performance was assessed using receiver-operating characteristic analysis and bootstrap internal validation.

Technical success was achieved in 276 of 354 interventions (77.9%). Independent predictors of success included favorable chronic total occlusion crossing approach based on plaque cap morphology (Types II and IV; P = .002), presence of distal outflow (P = .001), and nonsevere calcification (peripheral arterial calcium scoring system: Grade <3; P < .001). The morphologic score (0-5 points) demonstrated progressively decreasing success rates with increasing scores (0: 97%; 1: 86%; 2: 83.6%; 3: 70%; 4: 44.4%; 5: 40.9%; P < .001). A cutoff value of ≥3 identified lesions with lower technical success rates (sensitivity, 74.4%; specificity, 69.2%). The model demonstrated an area under the curve of 0.783. The adverse event rate was 12.2%, with most events classified as mild.

Presence of distal outflow and favorable chronic total occlusion crossing approach based on plaque cap morphology were associated with increased technical success, whereas severe calcification was associated with lower success rates. The proposed scoring system may provide a preliminary framework for procedural risk stratification; however, it remains exploratory and requires external validation before potential clinical application.