The risk of amputation is particularly high during the first 6 months following revascularisation for CLI. IC patients have a benign course in terms of limb loss. Mortality in both IC and CLI patients is substantial. Revascularised CLI patients have different comorbidities from IC patients.

Renal insufficiency is the strongest independent risk factor for both amputation and amputation/death in revascularised CLTI patients, followed by diabetes and heart failure. Men with CLTI have worse outcomes than women. These results may help govern patient selection for revascularisation procedures. Statin and low dose acetylsalicylic acid are associated with an improved limb outcome. This underlines the importance of preventive medication to reduce general cardiovascular risk and increase limb salvage.

This paper aimed to study the agreement and repeatability, both intra- and interobserver, of infrapopliteal lesion assessment with magnetic resonance angiography (MRA), using the TransAtlantic Inter-Society Consensus (TASC) II criteria, with perioperative digital subtraction angiography (DSA) as a reference. Sixty-eight patients with an MRA preceding an endovascular infrapopliteal revascularization were included. Preoperative MRAs and perioperative DSAs were evaluated in random order by three independent observers using the TASC II classification. The results were analyzed using visual grading characteristics (VGC) analysis and Krippendorff’s α. No systematic difference was found between modalities: area under the VGC curve (AUCVGC) = 0.48 (p = 0.58) or intraobserver; AUCVGC for Observer 1 and 2 respectively, 0.49 (p = 0.85) and 0.53 (p = 0.52) for MRA compared with 0.54 (p = 0.30) and 0.49 (p = 0.81) for DSA. Interobserver differences were seen: AUCVGC of 0.63 (p < 0.01) for DSA and 0.80 (p < 0.01) for MRA. These results were confirmed using Krippendorff’s α for the three observers showing 0.13 (95% confidence interval (CI) −0.07–0.31) for MRA and 0.39 (95% CI 0.23–0.53) for DSA. Poor interobserver agreement was also found in the choice of a target vessel on preoperative MRA: Krippendorff’s α = 0.19 (95% CI 0.01‒0.36). In conclusion, infrapopliteal lesions can be reliably determined on preoperative MRA, but interobserver variability regarding the choice of a target vessel is a major concern that appears to affect the overall TASC II grade.

WHAT THIS PAPER ADDSThe procedure-related amputation rate is insufficiently investigated. Revascularization for intermittent claudication confers a low but existing risk of procedure related major amputation within the first post-procedural year.Objective: To investigate the risk of procedure-related major amputation attributable to revascularization for intermittent claudication (IC) in a population-based observational cohort study. Methods: All patients who underwent open or endovascular lower limb revascularisation for IC in Sweden between 12 May 2008 and 31 December 2012 were identified from the Swedish National Quality Registry for Vascular Surgery (Swedvasc) and data on above ankle amputations were extracted from the National Patient Registry. Any uncertainty regarding amputation level and laterality was resolved by reviewing medical charts. For the final analysis, complete medical records of all patients with IC, having ipsilateral amputation after the revascularisation procedure, were reviewed. Patients wrongly classified as having IC were excluded. Ipsilateral amputations within one year of the revascularisation were defined as procedure related. Results: Altogether, 5 860 patients revascularised for IC were identified of whom 109 were registered to have undergone a post-operative ipsilateral lower limb amputation during a median follow up of 3.9 years (standard deviation 1.5 y). Seventeen were duplicate registrations and 51 were patients with chronic limb threatening ischaemia, misclassified as IC in the registry. One patient had not undergone any revascularisation, one was revascularised for a popliteal artery aneurysm, one was revascularised for acute limb ischaemia, one had a minor amputation only, and one patient was not amputated at all. Twenty-seven were amputated more than one year after the procedure. Thus, the major amputation rate within one year of revascularisation for IC was 0.2% (n ¼ 9/5 860). Conclusion: Revascularisation for IC in a contemporary setting confers a low but existing risk of procedure related major amputation within the first post-procedural year.