Percutaneous Transluminal Angioplasty for Infrapopliteal Chronic Limb-Threatening Ischemia: A Systematic Review and Meta-analysis of Primary Patency and Binary Restenosis Rates

Abstract

Purpose: Percutaneous transluminal angioplasty (PTA) remains the mainstay of endovascular therapy for infrapopliteal chronic limb-threatening ischemia (CLTI), but outcomes have not been well characterized using high-quality data. The aim of this meta-analysis was to provide an updated benchmark for rates of primary patency and binary restenosis after PTA using prospectively collected, predominantly core-lab adjudicated randomized controlled trial (RCT) data. Materials and methods: MEDLINE, EMBASE, Cochrane Central, and ClinicalTrials.gov were queried for RCTs published through November 2022 using PTA as a control arm and including patients with infrapopliteal CLTI. Studies were excluded if >25% of patients had intermittent claudication, other vessels were included, or primary patency or binary restenosis were not outcomes. Outcomes were analyzed using random effects models. This analysis was publicly registered (PROSPERO ID#394543). No funding was utilized. Results: Seventeen RCTs were included (1048 patients, 1279 lesions). Pooled primary patency rates using data from 6 RCTs were 68% at 6 months (95% confidence interval [CI]=45%–84%) and 66% at 12 months (95% CI=51%–79%). Pooled binary restenosis rates using data from 11 RCTs were 54% at 6 months (95% CI=33%–73%) and 60% at 9 to 12 months (95% CI=39%–78%). Significant heterogeneity was present in all outcomes (I2>50%, p<0.0001). Publication bias was not observed (Egger’s p>0.1). Conclusions: This meta-analysis provides estimates for binary restenosis and primary patency following PTA utilizing prospectively collected, predominantly core-lab adjudicated data. Results demonstrate 1-year primary patency rates that are 10% to 20% higher than what has been historically used in power calculations. These new estimates will help facilitate more accurate power analysis for future RCTs. Clinical Impact: Rates of primary patency and binary restenosis after percutaneous transluminal angioplasty (PTA) have not been well-described using high-quality data, and investigators have been utilizing estimates of 40% to 50% and 45% to 65%, respectively, when performing power calculations for trials. This meta-analysis demonstrates using high-quality, prospectively collected, and predominantly core-lab adjudicated randomized controlled trial data that actual rates of primary patency are closer to 60% up to 1 year following PTA and provides the first meta-analysis estimate of binary restenosis rates up to 1 year after PTA. These estimates will help facilitate more accurate power calculations for future RCTs in this space.