Pedal Arch Patency Guarantees Wound Healing and Limb Salvage of Transmetatarsal Amputation Following Limb Revascularization

Abstract

Introduction - Transmetatarsal amputation(TMA) is necessary whenever several toes or the forefoot are affected by gangrene due to peripheral arterial disease (PAD). Revascularization before TMA is mandatory to guarantee wound healing. Currently, factors that may affect TMA healing are not well investigated. The study's aim was to evaluate the role of foot arteries in TMA healing and limb salvage after revascularization. Methods - All patients treated for PAD with chronic limb threatening ischemia(CLTI) between April-2012 and November-2017 were collected in a prospective database. Retrospective analysis was performed including only patients who underwent TMA after any type of revascularization (surgical, endovascular). Patient's demographics and clinical characteristics were assessed. Pre-operative digital subtraction angiography(DSA) were reviewed together with interventional data to determine the patency of foot arteries and the presence of in-line flow to the foot. The pedal arch patency was classified1 as: no pedal arch(NPA), incomplete pedal arch(IPA) and complete pedal arch(CPA). Clinical and Duplex follow-up was performed at 3,6 and every 6 month thereafter. The study's primary endpoints were: wound healing (WH), Limb Salvage(LS) and impact of foot arteries and pedal arch patency on LS and WH on the basis of Chi square test and Log-Rank test in the Kaplan-Meier analysis. Secondary endpoints were: primary(PP), assisted(AP) and secondary patency(SP) and patient survival(S). Results - A total of 112 limbs in 105 patients (median age 72 ±10 years, male 76.2%, 7 patients treated bilaterally) satisfying the inclusion criteria were treated in the study period. Complete data on the foot arteries were available in 104(93%) limbs. Coronary artery disease, diabetes mellitus, kidney disease and chronic obstructive pulmonary disease(COPD) were present in 39.6%, 67.6%, 52%(dialysis 28.1%) and 38.4%, respectively. Clinical presentation was Rutherford stages 5 and 6 in 10.7% and 89.3%, with 69.7% of wounds presenting infection. Surgical and endovascular revascularization were performed in 37.5% and 62.5% of cases with a technical success of 87.5%. Dorsalis pedis and common plantar arteries patency, NPA, IPA and CPA were found in 55.8%, 54.8%, 21.2%, 60.6% and 18.3%, respectively. Direct in-line flow to the foot arteries was achieved in 72.1% of cases. The mean follow-up was 17.7 months. WH was 57.1%, 89.3% and 98.2% at 6,12 and 24-month, respectively. LS was 81.1%, 79.5% and 77.5% at 6,12 and 24-month, respectively. The study's secondary endpoints are reported in table 1. TMA healing and limb salvage were not affected by patency of either dorsalis pedis artery or plantar artery (P=0.26 and P=0.33, respectively). Similarly, direct in-line flow was not associated with better wound healing and limb salvage rates (P=0.12 and P=0.35, respectively). In contrast, the presence of CPA compared to IPA or NPA was associated with higher wound healing (at 12-month: 93.3% vs 83.3%. P=0.01) and limb salvage rates (at 12-month: 100% vs 75%. P=0.019).Table 1secondary endpoints at 6,12 and 24-monthPP (%)AP (%)SP (%)S (%)6-month68.471.177.869.112-month57.362.571.86424-month50.855.668.452.1 Open table in a new tab Conclusion - The study results suggest that the pedal arch patency has a principal role in wound healing and limb salvage after transmetatarsal amputation in patients with CLTI undergoing limb revascularization.