Non-compressible ABIs are associated with an increased risk of major amputation and major adverse cardiovascular events in patients with critical limb ischemia.

Ankle-brachial indices (ABIs) are important for the assessment of disease burden among patients with peripheral artery disease. Although low values have been associated with adverse clinical outcomes, the association between non-compressible ABI (ncABI) and clinical outcome has not been evaluated among patients with critical limb ischemia (CLI). The present study sought to compare the clinical characteristics, angiographic findings and clinical outcomes of those with compressible (cABI) and ncABI among patients with CLI. Consecutive patients undergoing endovascular evaluation for CLI between 2006 and 2013 were included in a single center cohort. Major adverse cardiovascular events (MACE) were then compared between the two groups. Among 284 patients with CLI, 68 (24%) had ncABIs. These patients were more likely to have coronary artery disease ( p=0.003), diabetes ( p<0.001), end-stage renal disease ( p<0.001) and tissue loss ( p=0.01) when compared to patients with cABI. Rates of infrapopliteal disease were similar between the two groups ( p=0.10), though patients with ncABI had lower rates of iliac ( p=0.004) or femoropopliteal stenosis ( p=0.003). Infrapopliteal vessels had smaller diameters ( p=0.01) with longer lesions ( p=0.05) among patients with ncABIs. After 3 years of follow-up, ncABIs were associated with increased rates of mortality (HR 1.75, 95% CI: 1.12-2.78), MACE (HR 2.04, 95% CI: 1.35-3.03) and major amputation (HR 1.96, 95% CI: 1.11-3.45) when compared to patients with cABIs. In conclusion, ncABIs are associated with higher rates of mortality and adverse events among those undergoing endovascular therapy for CLI.

Midterm Outcomes After Infrapopliteal Interventions in Patients With Critical Limb Ischemia Based on the TASC II Classification of Below-the-Knee Arteries.

PURPOSE: To analyze the relationship between the new TransAtlantic Inter-Society Consensus (TASC II) infrapopliteal classification and limb outcomes among patients with critical limb ischemia (CLI). METHODS: A single-center retrospective study was performed on 166 consecutive CLI patients (mean age 71 years; 113 men) undergoing endovascular treatment of 244 infrapopliteal lesions from 2006 to 2013. Patient, procedural, angiographic, and limb outcomes were compared for the new TASC A/B vs C/D classification for infrapopliteal lesions. Binary restenosis was determined by a peak systolic velocity ratio >2.0 by duplex ultrasound on follow-up at 1, 3, 6, and 12 months. RESULTS: Seventy-two (43.4%) patients had TASC A/B lesions, while 94 (56.6%) had TASC C/D patterns of infrapopliteal disease. Baseline demographics and tissue loss (93% vs 94%, p=0.59) were similar between the groups. TASC A/B lesions were shorter (53±35 vs 170±83 mm, p<0.001), less severely stenosed (77%±24% vs 93%±14%, p<0.001), had a larger target vessel diameter (2.9±0.5 vs 2.6±0.5 mm, p<0.001), and were less frequently chronic total occlusions (24% vs 64%, p<0.001) compared with the TASC C/D group. Three-year freedom from both amputation (85% vs 67%, p=0.02) and major adverse limb events (79% vs 61%, p=0.02) were significantly higher in the TASC A/B group. Technical success rates (95% vs 80%, p<0.001) and 1-year primary patency (58% vs 51%, p=0.04) were higher in the A/B group. Overall 3-year survival was similar between the groups (96% A/B vs 88% C/D, p=0.2). CONCLUSION: TASC C/D infrapopliteal lesions are associated with higher amputation and major adverse limb events rates and lower primary patency compared with TASC A/B infrapopliteal lesions. Further studies are needed to assess the association between TASC C/D infrapopliteal lesions and clinical outcomes in patients with CLI.