Pedal medial arterial calcification influences the outcomes of isolated infra-malleolar interventions for chronic limb-threatening ischemia.

Objective: Inframalleolar disease is present in most diabetic patients presenting with tissue loss. Inframalleolar (pedal) artery disease and pedal medial arterial calcification (pMAC) are associated with major amputation in patients with chronic limb-threatening ischemia (CLTI). This study aimed to examine the impact of pMAC on the outcomes after isolated inframalleolar (pedal artery) interventions.

Methods: A database of lower extremity endovascular intervention for patients with tissue loss between 2007 and 2022 was retrospectively queried. Patients with CLTI were selected, and those undergoing isolated inframalleolar intervention on the dorsalis pedis and medial and lateral tarsal arteries and who had foot x-rays were identified. X-rays were assessed blindly for pMAC and scored on a scale of 0 to 5. Patients with concomitant superficial femoral artery and tibial interventions were excluded. Intention to treat analysis by the patient was performed. Amputation-free survival (survival without major amputation) was evaluated.

Results: A total of 223 patients (51% female; 87% Hispanic; average age, 66 years; 323 vessels) underwent isolated infra-malleolar intervention for tissue loss. All patients had diabetes, 96% had hypertension, 79% had hyperlipidemia, and 63% had chronic renal insufficiency (55% of these were on hemodialysis). Most of the patients had Wound, Ischemia, and foot Infection (WIfI) stage 3 disease and had various stages of pMAC: severe (score = 5) in 48%, moderate (score = 2-4) in 31%, and mild (score = 0-1) in 21% of the patients. Technical success was 94%, with a median of one vessel treated per patient. All failures were in severe pMAC. Overall, major adverse cardiovascular events was 0.9% at 90 days after the procedure. Following the intervention, most patients underwent a planned forefoot amputation (single digit, multiple digits, ray amputation, or trans-metatarsal amputation). WIfI ischemic grade was improved by 51%. Wound healing at 3 months was 69%. Those not healing underwent below-knee amputations. The overall 5-year amputation-free survival rate was 35% ± 9%. The severity of pMAC was associated with decreased AFS.

Conclusions: Increasing severity of pMAC influences the technical and long-term outcomes of infra-malleolar intervention in diabetes. Severe pMAC is associated with amputation and should be considered as a variable in the shared decision-making of diabetic patients with CLTI.