The Relationship Between the Global Limb Anatomic Staging System and Midterm Outcomes of Subintimal Angioplasty of Superficial Femoral Artery Atherosclerotic Disease in Chronic Limb Threatening Ischemia

Abstract

Background: Superficial femoral artery (SFA) is commonly affected with atherosclerotic peripheral arterial disease leading to chronic limb-threatening ischemia (CLTI). Subinitimal angioplasty (SIA) is a minimally invasive option. We aimed to examine the relationship between the Global Limb Anatomic Staging System and SIA midterm limb and survival-related outcomes. Method: A prospective observational study was conducted on all patients with CLTI (Rutherford 4–6 or WIFI stages 2–4), with diseased femoropopliteal segment underwent SIA from August 2020 to September 2021. Patients with non-atherosclerotic SFA occlusion and those requiring primary major amputation were excluded. Multivariable Cox proportional hazard regression was performed to assess possible predictors of midterm clinical outcomes. Kaplan-Meier survival curves were used to estimate limb-based patency (LBP), limb salvage, amputation-free survival (AFS), and overall survival. Results: The study included 138 patients with CLTI due to chronic total occlusion of the SFA and underwent SIA ± treatment of associated ipsilateral hemodynamically significant inflow/outflow disease. Primary technical success was achieved in 116 cases (84%), with primary patency at 1, 6, and 12 months being 100%, 84%, and 79% respectively, while the limb-salvage rate at 6 and 12 months was 100% and 94%, respectively. The result of the comparison between CLASS 1 and Global Limb Anatomic Staging System III (GLASS III) revealed significantly worse patency with GLASS III (p=0.005), and better overall survival (p=0.037), limb salvage (p=0.021), and AFS (p<0.001) with GLASS I. Conclusion: Subinitimal angioplasty is a safe, effective, and minimally invasive treatment option for lengthy SFA lesions by avoiding the patients’ anesthesia and operative risk. Our study suggests that the GLASS stage may be a useful predictor of midterm limb and survival-related outcomes of this approach. GLASS III anatomy in comparison with GLASS I is associated with a statistically significantly worse LBP, limb salvage, AFS, and overall survival. Clinical Impact This study is discussing a very hot interesting challenging topic in vascular surgery and its management as SFA atherosclerotic lesion is the most common lesion faced by vascular surgeons subintimal angioplasty SIA is considered feasible and effective method in dealing with this lesion with accepted durability and lower rates of complications.The subintimal angioplasty is made by opening an extraluminal track behind the intimal layer and between the media and intima of the artery surrounding atherosclerotic plaque and thrombus. Hence, the track has a low thrombus or plaque burden content, making the SIA easier than intraluminal angioplasty and with comparable results. GLASS stage III was an independent predictor of loss of LBP, worse AFS, and major amputation.