Patterns of Angiographic Remodeling Following Foot Vein Arterialization

Foot vein arterialization (FVA) in no-option patients with chronic limb-threatening ischemia (CLTI) provides promising rates of limb salvage and wound healing; however, the precise mechanisms underlying tissue perfusion after FVA are not fully understood. In most cases, FVA creates an arterialized circuit confined inside the foot vein fortress (FVF) upon initial completion. Over the following weeks to months, FVA facilitates a process of vascular remodeling leading to tissue perfusion. The primary objective of this study is to describe a novel classification system of the angiographic patterns of vascular remodeling observed in FVA and to hypothesize their pathophysiology and implications for limb salvage.

This is a retrospective observational case series. We included no-option CLTI patients who underwent clinically-successful FVA (defined as achieving limb salvage with complete wound healing) and clinically-driven angiographic studies during follow-up. We identified 6 types of vascular remodeling: type 0, the arterialized circuit is confined inside the FVF; type 1, expansion of the arterialized circuit into venous systems outside the FVF; type 2, wound-related vascular remodeling leading to wound blush (WB); type 3, venous-arterial fistulas recruiting hibernated arterial segments; type 4, self-pruning of venous outflow; and type 5, promotion of collateral vessel growth with reconstitution of a new calf/foot distribution system.

Nineteen patients (12 with hybrid, and 7 with totally percutaneous FVA) were evaluated. The acute result of FVA showed a type 0 pattern in 13 patients (68.4%) and type 1 pattern in 6 (31.6%). During follow-up, patients required 43 new clinically-driven angiographic studies (mean 2.3/patient). The average time between initial FVA and subsequent angiographic studies was 164 ± 325.2 days (2-1895). In the 43 follow-up angiograms, the following pattern distribution was observed: type 0 pattern in 5 (11.6%), type 1 in 29 (67.4%), type 2 in 18 (41.9%), type 3 in 10 (23.3%), type 4 in 4 (9.3%), and type 5 in 7 (16.3%).

Vascular remodeling after FVA is a complex process involving multiple pathophysiological mechanisms, resulting in various angiographic patterns. Recognizing these patterns may aid clinicians in developing targeted treatments to enhance FVA efficacy and improve clinical outcomes.Clinical ImpactThis study introduces the first classification of angiographic patterns of vascular remodeling following foot vein arterialization (FVA), addressing the significant unpredictability of clinical outcomes despite high technical success in no-option CLTI patients. The primary clinical impact is providing a standardized framework to monitor and interpret the complex FVA maturation process. By recognizing the temporal evolution of these distinct patterns, clinicians can identify patients with suboptimal remodeling. This allows for targeted secondary interventions to guide vascular pathways, enhance tissue perfusion, and ultimately improve rates of wound healing and limb salvage, laying the groundwork for optimizing this limb-saving therapy.