Outcomes of Duplex-Guided Paramalleolar and Inframalleolar Bypass in Patients with Critical Limb Ischemia.

Background: The aim of the study was to evaluate the outcomes of duplex ultrasonography (DUS)-guided autologous vein bypass to paramalleolar (distal third of tibial arteries and peroneal artery) and inframalleolar arteries (dorsalis pedis, common plantar, medial, and lateral plantar arteries) in patients with critical limb ischemia (CLI) and extensive tibial artery disease Trans-Atlantic Inter-Society Consensus D.

Methods: Between January 2007 and October 2016, all paramalleolar or inframalleolar bypasses performed in patients with CLI, planned only on the basis of DUS, were collected and analyzed retrospectively. DUS evaluation included arterial disease extension, inflow and outflow arteries' diameter, outflow vessels resistance, and autologous veins quality. Patient's demographics and clinical characteristics were assessed. Tissue loss was graded according to Texas University Wound Classification (TWC). Follow-up included periodic clinical and DUS examinations. Primary end points were technical success (TS) (patent bypass with distal anastomosis performed on the Duplex-selected runoff artery, without stenosis >30% and in line flow with the inframalleolar arteries at completion angiography and without hemodynamic bypass stenosis at postoperative DUS) and bypass patency (primary [PP], assisted [AP], and secondary [SP]). Secondary end points were perioperative and follow-up patient survival (PS), limb salvage (LS), and amputation-free survival (AFS). Descriptive statistics and Kaplan-Meier analysis were performed. Univariate and Multivariate Cox analyses were used to define risk factors.

Results: Seventy-four bypasses in 73 patients with CLI (Rutherford 5-6 93.2%, TWC stage III in 63.5% and grade D in 48.6%) were performed in the study period (January 2007-October 2016). diabetes mellitus, coronary artery disease, and kidney disease were present in 67.6%, 60.8%, and 37.8% patients, respectively. Distal anastomosis was performed at the paramalleolar and inframalleolar arteries in 47.3% and 52.7%, respectively. Only autologous veins were used as conduit. TS was 98.6%. At 1-month, PP, AP, SP, PS, LS, and AFS were 87.8%, 91.9%, 93.2%, 95.9%, 94.6%, and 90.5%, respectively. The mean follow-up was 33.7 months; at 1-year, PP, AP, SP, PS, LS, and AFS were 54.4%, 71.4%, 75.1%, 89.9%, 84.3%, and 79.1%, respectively, and at 3-year, 42.3%, 63%, 66%, 67.5%, 80.6%, and 61%, respectively. At univariate and multivariate analyses, arterial hypertension was protective for PP (P = 0.035) while insulin-dependent diabetes was a negative predictor (P = 0.01); insulin-dependent diabetes was a negative predictor of LS (P = 0.002); TWC grade D was a negative predictor of AP (P = 0.047) and SP (P = 0.013). Age (P < 0.001) and major amputation (P = 0.014) resulted as negative predictors of PS.

Conclusions: Bypass of the Duplex-selected paramalleolar and inframalleolar arteries in CLI has high TS and high rate of perioperative and late LS. Duplex evaluation and planning in CLI patients with extensive tibial arteries disease is associated with efficacy of surgical revascularization and high LS rates.