Critical limb ischemia carries a significant risk of limb loss. Within 1 year of presentation, up to 40 % of patients require a major amputation and up to 20 % have died. The overall 30-day mortality of a major amputation, defined here as either a below-the-knee (BKA) or above-the-knee (AKA) amputation, is 8 % with a 30-day overall complication rate of 30 %. Nelson et al. demonstrated 30-day mortality rates for BKA and AKA of 6.5 % and 12.8 %, respectively [2]. Aulivola et al. arrived at similar conclusions with 30-day mortality rates for BKA and AKA of 5.7 % and 16.5 % respectively [3]. In addition, they found 1-year survival rates to be 74.5 % after a BKA and 50.6 % after an AKA. Astonishingly, 1/2 of all patients requiring an AKA had died within 1 year of surgery. Fortunately, revascularization has a profound positive impact on limb salvage rates for patients with critical limb ischemia. Hallett et al. were able to show a 50 % reduction in major amputation rates for patients undergoing either surgical or endovascular reconstruction [4]. Limb salvage, therefore, becomes a critical endpoint when determining the benefit of limb revascularization to the patient and the ultimate success of an operation.

Claudication carries a minimal risk of limb loss, approaching 5 % at 5 years [5]. Operative intervention to correct claudication is performed with the hope of improving the patient’s QOL. Dumville et al. published data supporting an improvement in QOL following bypass surgery using the Medical Outcomes Study Short Form-36 Health Survey (SF-36) [6]. QOL also becomes important in patients with CLI. Patients are at risk of losing their mobility and independence after undergoing a major amputation. Only 80 % of patients receiving a BKA are able to ambulate vs. 50 % of patients with an AKA. In addition, amputees are more prone to depression as they struggle to come to terms with the loss of their limb. Revascularization for lifestyle-limiting claudication and CLI, therefore, becomes an important means by which to increase the patient’s QOL.

Most studies relating to extra-anatomic bypasses for AIOD focus on one type of bypass (either axillofemoral or femorofemoral) to the exclusion of the other. Additionally, most do not include aortobifemoral direct anatomic bypass in their analysis. Overall, this limits the interpretation of the data in regard to limb salvage and quality of life. However, limb salvage is an outcome in most of the studies included herein. Quality of life is rarely measured directly but graft patency, ankle-brachial indices, and symptom-free survival may be considered surrogates for this elusive outcome.

Berce et al. performed a retrospective analysis of their personal experience with Femorofemoral bypass (FFB) surgery for AIOD [7]. Their goal was to demonstrate that FFB was safer than performing anatomic aortoiliac surgery. Limb salvage was one outcome they considered. This study involved 211 patients, all of whom underwent surgery for claudication. None had surgery for CLI. No other types of extra-anatomic bypasses were performed. Limb salvage at 1, 5, and 10 years was 99 %, 97 %, and 97 %, respectively (Table 13.3). Limb patency appeared to be excellent, but only claudicants were included in the study. Quality of life was not directly measured. Graft patency, however, was measured (Table 13.4). Graft patency at 1, 5, and 10 years was 96 %, 72 %, and 64 %, respectively. Overall, the GRADE of this study in regard to limb salvage is deemed low quality. The reason the study was assigned a grade of low quality was because the study was retrospective in design and did not directly compare limb salvage rates to direct anatomic revascularization. In addition, the study enrolled only patients suffering from claudication and not CLI. The GRADE of this study for quality of life is deemed very low. A higher grade could not be assigned as quality of life was not a directly measured outcome. Only an indirect assumption about EAB impact on quality of life could be gained based on patency rates.