Approach to revascularization for claudication due to peripheral artery disease

INTRODUCTION — Patients with peripheral artery disease (PAD) can be asymptomatic or present with symptoms ranging from pain with walking (intermittent claudication) to severe signs of ischemia (rest pain, tissue loss). Intermittent claudication, which is a reproducible discomfort of a specific group of muscles (buttock, thigh, calf) induced by exercise and relieved with rest, is due to atherosclerotic occlusive disease primarily located in the aorta, iliac, femoral, or popliteal arteries.

The goals of treatment in patients with claudication are to improve functional abilities and control systemic atherosclerotic disease. Conservative medical therapies are the initial treatment of choice and include cardiovascular risk reduction, exercise therapy (supervised if available), and possibly pharmacologic therapy to improve walking distance. Once all available conservative treatments have been instituted and allowed to have an effect, the patient's symptoms are re-evaluated. If symptoms are controlled, no further action is required. However, if symptoms persist and are lifestyle limiting and the patient has been responsive to adjusting their lifestyle, the risk-benefit ratio of intervention, either endovascular or open, should then be evaluated.

The general approach to revascularization in patients with claudication is reviewed. The clinical features, diagnosis, and medical management in patients with claudication are reviewed separately. (See "Clinical features and diagnosis of lower extremity peripheral artery disease" and "Management of claudication due to peripheral artery disease".)

CLINICAL CRITERIA FOR REVASCULARIZATION — For most patients with claudication, the decision to intervene should be offered only after they have adhered to and failed optimal medical management. However, for some patients, a combination of exercise therapy and endovascular intervention may provide a greater improvement in walking distance compared with exercise alone or PTA alone [1-5]. (See "Management of claudication due to peripheral artery disease", section on 'Approach to management'.)

General considerations — Revascularization is highly individualized and oriented toward patient-centered goals based on clinical assessment. The main goal of revascularization is functional improvement, taking into consideration the potential for improvement in quality of life or exercise rehabilitation, rather than based purely on the presence of a stenotic lesion on imaging or extent of anatomic involvement. Thus, during the evaluation, it is important to understand the severity of the patient's disability (pain-free walking distance, maximum walking distance), as well as how much this impacts their daily activities. (See 'Clinical evaluation' below.)

Any proposed revascularization should provide a meaningful functional benefit for the patient that outweighs the potential risks associated with revascularization, which differs for an endovascular approach compared with an open surgical approach. A major concern with intervention in patients with claudication is that some patients may suffer early and late complications that worsen their symptoms or increase the risk of developing limb-threatening ischemia potentially resulting in major limb amputation. (See 'Progression to limb-threatening ischemia' below.)

The durability of the anticipated revascularization also plays an important role, and the planned intervention is selected based on the medical condition of the patient, the anatomic complexity of disease, and the patient's activities of daily living to provide optimal early and late anatomic and functional outcomes.

Guideline criteria — We agree with multidisciplinary guidelines that suggest the following criteria should be satisfied when considering intervention (algorithm 1) (endovascular or surgical) in patients with claudication [6-13]:

●The patient is significantly disabled by claudication, resulting in an inability to perform normal work or other activities that are important to the patient. This criterion reflects the symptom variability among patients with claudication and the impact of these symptoms on the patient's quality of life. Numerous studies have shown that successful revascularization can substantially improve the patient's quality of life [14-16]. However, there may be substantial differences between the patient's and the physician's assessments of the quality of life [14].

●The patient has not had or is not predicted to have an adequate response to exercise rehabilitation and/or pharmacologic therapy.

●The anatomic characteristics of the lesion(s) permit appropriate intervention at low risk with a high likelihood of initial and long-term success. Success is defined as a more than 50 percent likelihood of sustained functional improvement, symptom relief, and anatomic patency for at least two years [8]. In younger patients, durability beyond two years should be considered during the shared decision-making process.

●The projected natural history of the disease and the overall prognosis of the patient should be taken into account.

●The patient will benefit from an improvement in claudication (ie, exercise is not limited by another cause, such as angina, heart failure, chronic obstructive pulmonary disease, or orthopedic problems).

CLINICAL EVALUATION — For patients with disabling claudication with refractory symptoms who meet the above clinical criteria, revascularization can be considered. (See 'Clinical criteria for revascularization' above.)

Determining whether endovascular (eg, angioplasty, atherectomy, stenting), surgical (eg, bypass, endarterectomy), or a hybrid approach to revascularization (or no revascularization) is more appropriate depends on the anatomic severity and extent of disease and the assessment of comorbidities and thus the patient's risk for the perioperative morbidity and mortality with the proposed intervention (algorithm 1). In addition, the patient's expected long-term (>2 years) survival, functional status, and specific goals of revascularization coupled to the patient and operator preference (and operator's long-term success rates) have a significant impact on determining the optimal approach and must be factored into the shared decision making. The availability of autologous veins is another determinant for those with femoro-popliteal disease.

●Endovascular intervention involves accessing typically the femoral artery with an arterial sheath and passing various wires or catheters to guide the placement of an expandable balloon and/or stent, a cutting device, or other devices at the presumed culprit lesion in the leg. Balloon angioplasty results in a "controlled" dissection of the arterial media, widening the lumen of the stenosed vessel. Atherectomy involves removal, morcellation, or evaporation of the plaque. Sculpting or cutting balloons allow for plaque modification to enhance balloon angioplasty and are often used as adjuncts to drug-eluting balloon angioplasty therapy. Adjunctive stenting might be needed if the vessel has a recalcitrant stenosis without appropriate luminal gain, develops elastic recoil or a flow-limiting dissection. It is common for several modalities to be combined to achieve a satisfactory result. (See "Endovascular techniques for lower extremity revascularization".)

●Surgical revascularization involves either focal removal of obstructing atherosclerotic plaque (endarterectomy) or surgical bypass of the obstruction. Bypass involves identifying an appropriate inflow vessel above the obstruction and a target vessel below the obstruction onto which to suture the selected graft; the appropriate conduit can be autogenous vein or prosthetic material. (See "Lower extremity surgical bypass techniques".)

●A hybrid approach (endovascular intervention combined with an open procedure) was initially described in patients undergoing bypass procedures (eg, femoro-femoral, femoro-popliteal) with endovascular intervention used to treat an inflow lesion (eg, focal aorto-iliac artery lesion). Endovascular intervention of the inflow lesion can be done before the planned bypass or simultaneously with the bypass procedure. Hybrid procedures have evolved to include endovascular treatment of complex lesions (eg, long occlusions) involving the inflow (iliac artery) and/or outflow (superficial femoral or deep femoral [profunda]) vessels, with femoral endarterectomy combined with a prosthetic patch being the most common open reconstruction.

Defining severity and extent — The severity of claudication is classified functionally by the initial and absolute walking distance and by the Society for Vascular Surgery Rutherford scale from 1 to 3. (See "Classification of acute and chronic lower extremity ischemia", section on 'Rutherford'.)

Specific options for revascularization depend upon the level of arterial obstruction as determined through vascular imaging. It is important when treating patients with claudication that the patient's symptoms correlate with the identified lesion(s) on imaging, particularly the lesions that will be treated.

The predominant site of lower extremity claudication pain and its severity depends not only on the location and severity of stenotic lesion(s), but also the collateral circulation and the vigor of exercise. The usual relationship between the site of pain and site of arterial disease can be summarized as follows (see "Clinical features and diagnosis of lower extremity peripheral artery disease"):

●Buttock and hip – aorto-iliac disease

●Thigh – aorto-iliac or common femoral artery

●Upper two-thirds of the calf – superficial femoral artery

●Lower one-third of the calf – popliteal artery

Buttock and thigh claudication from aorto-iliac or common femoral artery disease (also called inflow disease) tends to be more disabling, and the threshold to intervene is generally lower than for more distal disease (algorithm 1). Options for treating inflow disease include aortic or iliac artery angioplasty and stenting, and aorto-iliac or aortofemoral bypass, among others. (See 'Revascularization to restore inflow' below.)

Calf claudication is usually due to the presence of disease distal to the inguinal ligament (ie, infrainguinal; also called outflow disease), typically a lesion is located in the superficial femoral or popliteal artery. Options for infrainguinal revascularization include balloon angioplasty/stenting/atherectomy of the superficial femoral artery, or femoral-to-popliteal bypass. Rarely, a more distal bypass may be needed to treat symptoms of claudication, but more typically, multilevel lesions and disease of the tibial vessels result in more severe symptoms (rest pain, ischemic ulcers). If a target distal to the popliteal artery is identified as the only viable target, the risk of limb loss increases, and the need for intervention should be revisited. (See 'Infrainguinal revascularization' below.)

Vascular assessment and imaging — The assessment of the patient with claudication includes a thorough vascular evaluation with pulse examination and measurement of pulse volume recordings of the leg and ankle-brachial index (resting and post-exercise). Particular attention should be given to the femoral artery examination, as the quality of the femoral pulses (present, weak, absent) provides the clinician with a good idea of the level of occlusive disease (ie, inflow [unilateral versus bilateral] versus outflow, or both) to help decide on the best imaging modality, if revascularization is indicated. (See "Clinical features and diagnosis of lower extremity peripheral artery disease".)

Once a decision has been made to intervene, the choice of imaging modality is based on the level of disease that requires intervention, as well as the patient's renal function and the presence of any allergies. The goal of vascular imaging is to assess the severity and extent of arterial disease and to aid selection and planning of intervention. It is important to emphasize that advanced vascular imaging should never be performed before a decision has been made for revascularization; the indication for intervention is never the anatomic complexity of the disease. (See 'Clinical criteria for revascularization' above.)

●For patients with suspected inflow disease (buttock or thigh claudication, weak or absent femoral pulse[s]) confirmed by noninvasive vascular studies, computed tomographic (CT) angiography is the preferred vascular imaging study. CT angiography provides valuable information regarding the extent and amount of calcium, thrombus content and extent, particularly in the aorta and ilio-femoral arteries, as well as the diameter of the vessels. In patients with chronic kidney disease, preoperative measures should be taken to decrease the risk of contrast nephropathy. (See "Advanced vascular imaging for lower extremity peripheral artery disease", section on 'Computed tomographic angiography'.)

●For patients with suspected outflow disease (calf or foot claudication, palpable femoral pulse[s], weak or absent popliteal pulse[s]) confirmed by noninvasive vascular studies, duplex ultrasound can be used to assess the anatomy and is often used as the initial noninvasive imaging. CT angiography may be preferred, as it will allow assessment of the wall quality (calcification) as well as extent of involvement and is very accurate for assessment of the femoro-popliteal segment. (See "Advanced vascular imaging for lower extremity peripheral artery disease", section on 'Digital subtraction angiography'.)

Magnetic resonance (MR) angiography can be considered as an alternative to CT angiography, especially in patients with mild-to-moderate chronic kidney disease if good-quality MR is available, particularly for patients with palpable femoral pulses; however, MR angiography tends to overestimate stenoses and cannot visualize arterial wall calcifications. It is also limited by motion artifacts, and patients with pacemakers, implants, and claustrophobia cannot have the exam.

Anatomic classification — Vascular imaging identifies the atherosclerotic pattern of disease, which can be classified by the TASC II guidelines for the iliac system and the femoral and popliteal lesions by the Global Anatomic Staging System (GLASS) criteria, which was originally developed to aid decision making in patients with PAD more severe than symptoms of claudication. Classifying the pattern of disease by its anatomic distribution, multiplicity of lesions, calcification, and the nature of the lesion (stenosis or occlusion) is important in determining outcomes.

●TASC II – TASC II presented a scheme that classified iliac, femoral, and popliteal lesions as type A, B, C, or D based upon overall success rates for treating a lesion using endovascular or surgical means at the time the classification was created [12,13]. The TASC II classification is now used for iliac lesions only. Within the iliac vessels, Type A lesions represent focal short stenosis of the arteries, which are more likely to be successfully treated with an endovascular intervention compared with type D lesions, which represent diffuse disease and chronic occlusions that are likely to require complex reconstruction or open surgical treatment to achieve durable improvement. (See "Classification of acute and chronic lower extremity ischemia", section on 'TASC classification'.)

Although the original TASC classification in the iliac arteries was designed to improve decision making for open surgical versus endovascular intervention (ie, TASC A: endovascular; TASC B/C: endovascular or surgical; TASC D: surgical), the TASC classification is used more for lesion classification rather than choosing the treatment modality. In fact, the majority of iliac artery TASC C/D lesions are initially treated by endovascular means for which patency rates are comparable to those reported for TASC A/B lesions. Newer techniques of iliac intervention for advanced iliac disease using covered stents now provides short-term (up to five years) equivalent outcomes to open surgery for TASC C/D iliac lesions [17-19]. (See 'Revascularization to restore inflow' below.)

●GLASS — The GLASS classification was designed to classify the vessels at the femoro-popliteal, tibial, and pedal level that would define the best pathway for blood to reach the foot (ie, the target arterial path [TAP]) [20]. Anatomic classification for each vascular segment of the leg is combined to allow three stages of complexity for intervention to be defined: GLASS stage 1, 2, and 3. These stages have predominantly been used in patients with chronic limb-threatening ischemia, although anatomic classification overall is shifting toward GLASS. (See "Classification of acute and chronic lower extremity ischemia", section on 'GLASS classification'.)

Within the GLASS system, factors that determine a successful anatomic outcome are intrinsically different for open surgical and endovascular revascularization. Open surgical bypass grafting requires adequate inflow and outflow and a suitable autologous conduit. By contrast, the success of endovascular intervention is largely defined by the complexity of atherosclerosis within the anticipated TAP.

Medical risk assessment — Patients with claudication have inherent global cardiovascular risk that must be assessed and factored into any shared decision making. In procedural risk calculators, vascular surgery procedures are considered an intermediate- to high-risk surgical procedure. As a result, preoperative risk stratification should be performed in all patients. Perioperative evaluation and risk assessment are discussed separately.

●(See "Evaluation of cardiac risk prior to noncardiac surgery" and "Management of cardiac risk for noncardiac surgery".)

●(See "Evaluation of perioperative pulmonary risk" and "Strategies to reduce postoperative pulmonary complications in adults".)

●(See "Frailty", section on 'Rapid screening tools'.)

Regardless of whether intervention is performed, all patients with claudication should undergo evaluation and treatment of atherosclerotic risk factors (eg, smoking, hypercholesterolemia, hypertension, hyperglycemia). Risk factor modification reduces the incidence of not only limb loss but also myocardial infarction. (See "Management of claudication due to peripheral artery disease", section on 'Approach to management'.)

INITIAL APPROACH

General principles — Since the early 2000s, endovascular interventions have increasingly been adopted due to their minimally invasive nature and the rapid development of various wall modulating technologies. Comparisons of patency rates and complications for endovascular versus open surgical revascularization from observational studies and a handful of randomized trials [21-28] have demonstrated similar cumulative patency rates in the midterm. Endovascular interventions are associated with fewer periprocedural complications but higher rates of restenosis, which can usually be managed with repeat intervention [29]. In addition, uncomplicated failed endovascular intervention does not appear to compromise subsequent surgical options and success. Based on these comparative outcomes, we continue to agree with various guidelines that generally favor an initial percutaneous revascularization, reserving surgery for when arterial anatomy is not favorable for an endovascular approach, provided the patient has an acceptable risk for surgery and adequate vein for bypass [7,12,13,30,31].

With advances in technology, almost all anatomic lesions can potentially be treated initially using endovascular techniques using antegrade or retrograde approaches. However, technical success, early and late patency rates, and overall durability of endovascular interventions are determined primarily by the anatomic complexity of occlusive disease and the technique used (eg, angioplasty versus drug elution angioplasty versus open stenting versus covered stenting). Length of stenoses and occlusions, location (eg, involvement of common femoral artery, popliteal artery and infrapopliteal arteries, trifurcation, ostial lesions), calcium content, and quality of the runoff vessels collectively describe the disease complexity and predict the likely outcome of an intervention, thus the optimal technique needed to achieve a successful revascularization. Anatomically less complex lesions can typically be initially treated with simpler endovascular techniques; however, for patients with more complex anatomy, decision making becomes more complicated and choice of techniques more sophisticated. Anatomically more complex lesions have one or more of the following features:

●Long-segment stenosis

●Multifocal stenoses

●Eccentric, calcified stenosis

●Long-segment occlusions

●Prior failed endovascular intervention with same segment

These features reflect more extensive and advanced disease and are typically associated with lower technical success and decreased durability for endovascular intervention. The success of intervention also depends on lesion location, with endovascular intervention for aorto-iliac ("inflow") lesions tending to have better long-term outcomes compared with interventions for infrainguinal ("outflow") lesions, even for more complex lesions. With the technological advancements in balloons, stents, atherectomy devices, and delivery systems, endovascular intervention can be offered to poor surgical candidates who would not otherwise have been treated, even in those with more extensive disease.

This general approach may differ in young patients (<40 years of age) with early onset PAD. Symptoms in this group of patients are typically due to a more aggressive atherosclerotic disease process than that experienced by most older patients with claudication. However, it is important to differentiate these patients from patients with collagen vascular disease and/or hypercoagulable disease. The aggressive nature of atherosclerosis in young individuals was demonstrated in a retrospective series of 29 vascular reconstructions in patients under the age of 40, 76 percent of which were for intermittent claudication [32]. The following results were noted:

●Average mortality rate at 10 years following initial surgery was 31 percent

●Initial vascular reconstructions failed in 72 percent, with an amputation rate of 17 percent

●At the end of the follow-up period, only 25 percent of surviving patients were asymptomatic

These results suggest that one should be cautious before considering revascularization (endovascular, surgical) for claudication in patients in this group.

Revascularization to restore inflow — Revascularization of arteries located proximal to the inguinal ligament (ie, aorta, common iliac artery, external iliac artery) restores inflow. Claudication resulting from inflow disease tends to be more disabling than isolated superficial femoral artery disease. Based on predominantly observational studies demonstrating similar cumulative patency rates and lower perioperative complication rates for endovascular aorto-iliac interventions, we suggest initial aorto-iliac angioplasty and stenting for most patients (unilateral or bilateral iliac involvement), even for the most complex anatomy, rather than open surgical revascularization [24,28,33-35]. Surgery can be offered to good-risk candidates if endovascular intervention has failed or is anticipated to fail.

Options for aorto-iliac revascularization include:

●Aortic disease – Aortic stent-grafting (covered endovascular reconstruction of the aortic bifurcation [CERAB]), aortofemoral bypass.

●Unilateral iliac (common iliac/external iliac) artery disease – Iliac artery angioplasty and stenting, unilateral aorto-iliac bypass, ilio-femoral bypass, or iliac endarterectomy.

●Bilateral iliac artery disease – Bilateral iliac angioplasty and stenting (kissing covered stents), CERAB, aortobifemoral bypass grafting, unilateral restoration of inflow (endovascular, surgical, hybrid) combined with femoral-femoral bypass.

The benefit-risk relationship for endovascular treatment of an iliac artery lesion is higher compared with treatment of lesions in the common femoral artery or superficial femoral artery. The threshold to intervene when treating claudication for inflow disease is generally lower than for outflow disease. While endovascular intervention has a higher benefit-risk ratio in the short term, durability is not as good as for surgical revascularization (eg, aortofemoral bypass). However, the general prognosis (ie, long-term survival) for patients with aorto-iliac disease is generally poorer compared with those who have more distal disease, independent of risk factors and comorbidities [36].

Endovascular interventions can be performed in any patient with aorto-iliac occlusive disease, even in those with most complex anatomy; however, juxtarenal occlusions, hypoplastic aortic syndrome, or those with concomitant aortic aneurysmal dilatation (small or large) with thrombus load present particular challenges. The increased use of CERAB in such cases offers a less invasive alternative and has become more popular, with comparable initial success to aortoiliac reconstructions.

Open surgical revascularization remains indicated for younger risk-appropriate patients with lifestyle-limiting claudication when endovascular intervention is not possible, when an initial endovascular attempt has failed, or where there is associated poor predicted durability (hypoplastic aortic, small diameter iliac arteries [eg, common iliac artery <8 mm, external iliac artery <6 mm]) and/or poor outflow.

Infrarenal aorta — Indications for aortic intervention are bilateral buttock and leg claudication with (Leriche syndrome) or without erectile dysfunction, the presence of hemodynamic evidence of impaired distal perfusion, and the presence of a stenosis in the infrarenal aorta that is not adjacent to a patent and large inferior mesenteric artery (IMA) or juxtaposed to the visceral vessels. This disease may be solitary or associated with concomitant iliac disease. Focal stenosis of the infrarenal aorta is relatively rare and occurs predominantly in young women who are heavy smokers and who have elevated lipid levels.

Aortic endarterectomy and aortic bypass surgery have been traditional treatment options for these lesions. The long-term results of surgery show excellent patency rates; however, surgery is associated with notable mortality and morbidity.

Aortic endarterectomy and aortic bypass surgery have been the more traditional treatment options for these lesions. The long-term results of surgery show excellent patency rates; however, surgery is associated with notable mortality and morbidity.

Endovascular intervention by balloon angioplasty combined with open or covered stent placement is more common, with comparable results to open therapies [37]. Placement of aortic endografts has been reported, but their design may lack sufficient radial force to overcome the intrinsic mural disease and recoil after balloon angioplasty. As most aortic interventions occur close to the bifurcation and involve the common iliac vessels, the introduction of CERAB, which entails a dedicated covered aortic stent and bilateral covered common iliac stents, has shown equivalent outcomes to open aortoiliac surgery [38]. If the anatomy is unsuitable for endovascular intervention due to long occlusions or small vessels, then an aorto-iliac or aortobifemoral bypass is chosen. Unilateral disease may be treated with recanalization of the occlusion and bi-iliac stenting or by unilateral aortofemoral, ilio-femoral bypass or rarely a crossover femoro-femoral bypass. The in-line bypasses are more durable than stenting but are associated with a higher mortality rate and complications compared with endovascular intervention.

Aorto-iliac segment — Atherosclerotic lesions in the aorto-iliac location generally begin at the bifurcation of the aorta or the common iliac arteries and can progress in either direction. In general, patients complaining of claudication due to isolated aorto-iliac disease tend to be younger than those whose claudication is due to disease of the femoro-popliteal segment.

Lesions of the aorto-iliac system may be less likely to cause symptoms compared with the distal lower extremity arteries since there is extensive collateral circulation in this region. On the other hand, claudication due to aorto-iliac disease can result in greater disability due to the large muscle groups directly perfused by these vessels. Furthermore, atherosclerotic lesions in this area, regardless of lumen diameter, are a potential risk for distal embolization; a complication commonly referred to as "blue toe syndrome" [39].

For these reasons, as well as the excellent long-term results obtained in these patients, a more aggressive approach is taken for patients with symptomatic aorto-iliac occlusive disease and claudication who would not otherwise be offered more distal procedures. After evaluation and institution of best medical therapies, early endovascular intervention may be offered. The absence or presence of bulky disease in the common femoral arteries (CFAs) determines whether a percutaneous approach to aorto-iliac angioplasty and stenting or a combined (hybrid) procedure is performed. Open common femoral endarterectomy and patch angioplasty are appropriate in 10 to 15 percent of patients undergoing aorto-iliac revascularization. Aorto-iliac angioplasty with stenting may be needed in patients undergoing intervention for femoro-popliteal disease with or without concomitant open femoral endarterectomy. (See 'Infrainguinal revascularization' below.)

Patients with aorto-iliac occlusive disease who are revascularized experience immediate relief of claudication symptoms, and the patency of the aorto-iliac endovascular interventions is excellent with a low risk for complications [38]. In the Claudication: Exercise Versus Endoluminal Revascularization (CLEVER) trial, while patients randomly assigned to supervised exercise therapy and best medical therapy had the greatest increase in walking distance, the quality-of-life improvement was greater for patients who had iliac stenting and best medical therapy [4].

Common/external iliac artery — Indications for iliac intervention are unilateral or bilateral buttock and leg claudication with or without erectile dysfunction. There may be an absence of hemodynamic and duplex evidence of impaired distal perfusion at rest, but this can be revealed by exercise testing. There must also be the presence of a stenosis or occlusion in the common or external iliac arteries. This disease may be solitary or associated with concomitant common femoral or superficial femoral artery disease.

Aortobifemoral and aorto-bi-iliac bypasses remain very durable procedures, with the location of the distal anastomosis and type of occlusive disease impacting patency and clinical efficacy. Retrospective reviews have not demonstrated any significant differences between the aortobifemoral bypass and endovascular intervention with respect to long-term rates of mortality, amputation, or revision procedures. Compared with aortobifemoral grafting, aorto-iliac stenting is associated with decreased perioperative morbidity, and shorter hospital stay [40-42]. While TASC II A and B iliac lesions respond very well to endoluminal intervention [43,44], the experience with TASC II C and D lesions is growing and showing good results, especially when covered stents are used in the aorta and iliac arteries [17,18,24,34,35,41,45,46]. In appropriately selected and risk-stratified individuals, aortobifemoral bypass continues to be performed safely, though with a higher perioperative (30-day) morbidity rate compared with percutaneous intervention, but this is counterbalanced by greater improvements in ankle-brachial index, symptom relief, and extended durability. In one study evaluating outcomes after surgical treatment for intermittent claudication, 62 percent of the procedures were inflow procedures, the great majority of which were for aorto-iliac disease [16]. Primary unassisted patency at four years for this group was 92 percent with no perioperative deaths.

As with all percutaneous procedures, iliac interventions are associated with the development of restenosis and the need for repeat intervention [43]. This increased use of covered stents in the common iliac arteries has reduced the incidence. The presence of a stenotic superficial femoral artery, poor runoff, external iliac artery disease, and female sex are independent predictors of worse outcome after iliac stenting [33,35,44,47-50]. Patients with extensive external iliac disease have a lower incidence of hemodynamic and clinical improvement and poorer long-term patency after endovascular iliac intervention [51]. Furthermore, external iliac artery stenting is an independent predictor of decreased primary patency in females but not in males [52]. Primary surgical aorto-iliac reconstruction may be an option for the younger patient, patients with small vessels, females, or those who have a failed prior endovascular intervention. However, best medical management may be preferred to vascular interventions in those with excessive, predicted short-term failure rates. Even in patients with significant symptoms, short-distance claudication is preferable to any risk for amputation.

The risk of complications associated with endovascular repair (eg, vessel rupture, dissection, early/late occlusion, loss of branch vessels, distal embolization) parallels the increase in the complexity of the revascularizations. In a large review, the complication rate in patients with higher TASC lesions was higher for C/D compared with A/B lesions (9 versus 3 percent), with significantly longer procedure times in a large study [17].

Internal iliac artery — A small subset of male patients experience buttock claudication with or without erectile dysfunction and are found on imaging to have uncompensated internal iliac artery disease, bilateral internal iliac artery stenosis, or a combination of stenosis and occlusion [53-56]. Balloon angioplasty is the most common intervention for this phenomenon and results in a high technical success with one-third of patients obtaining complete relief, one-third of patients having partial relief, and one-third of patients with no meaningful relief of their buttock claudication symptoms.

Infrainguinal revascularization — For most patients with claudication and superficial femoral-popliteal disease, based on several randomized trials and observational studies [21-23,25-29], we suggest initial endovascular treatment, rather than surgical bypass (vein or graft conduit). Surgery can be offered to good-risk candidates if endovascular intervention has failed or is anticipated to fail (eg, common femoral disease, severe long-segment superficial femoral stenosis/occlusion, distal popliteal disease). When selected, open surgical revascularization has a high cumulative patency with near-zero perioperative mortality in good-risk surgical candidates. (See 'Femoro-popliteal segment' below.)

We do not recommend treatment of infrapopliteal disease (ie, tibial vasculature) in patients with PAD in the absence of chronic limb-threatening ischemia (CLTI). In most cases, multiple lesions at various levels, and particularly more distal disease (tibial vessels), are required for a patient to progress to CLTI. (See 'No role for infrapopliteal intervention' below and "Management of chronic limb-threatening ischemia".)

Options for infrainguinal revascularization appropriate for claudication include:

●Common femoral artery disease – open endarterectomy, open patch angioplasty, atherectomy

●Femoro-popliteal disease – angioplasty (plain balloon, drug-eluting balloon, scoring/cutting balloon, lithotripsy) with or without stenting (plain stent, covered stent, drug-eluting stent), atherectomy (directional, orbital, rotational, and laser atherectomy), open surgical bypass

Common femoral artery — The indication for common femoral intervention is unilateral leg claudication meeting the criteria discussed above and the presence of a stenosis or occlusion in the common femoral artery on vascular imaging (see 'Clinical criteria for revascularization' above). Hemodynamic evidence of impaired distal perfusion at rest may be absent but can be revealed by exercise testing. For good-risk surgical candidates, we suggest open surgical revascularization as the initial vascular intervention, rather than an endovascular approach. The long-term primary patency rate is better after open versus endovascular revascularization but open surgery has a higher risk of perioperative mortality and complications [57].

Patients with bulky common femoral artery disease with or without extension proximally or distally are generally best treated with common femoral endarterectomy and patch angioplasty, with or without a profundoplasty. Common femoral endarterectomy is safe and effective with durable outcomes [58]. For patients treated for isolated common femoral disease, future interventions proximal or distal to the endarterectomized site can be expected in one-third of patients [59]. Combining common femoral endarterectomy with iliac intervention provides acceptable long-term results [45]. Following common femoral endarterectomy, surgical site infection is the main complication. Prior arterial surgery in the groin and use of a postoperative wound drain are independent predictors of the development of a surgical site infection [60]. The type of patch used does not affect the risk for surgical site infection.

The anatomic environment is generally less favorable for endovascular intervention because the common femoral artery overlays the hip and is subject to flexion and contraction. In medically very high-risk patients, endovascular intervention (angioplasty alone or with drug delivery (ie, drug-eluting stents), and atherectomy have been reported for both common and deep femoral (ie, profunda femoris) arterial disease [61-63]. Angioplasty can use a conventional balloon or a "cutting/scoring" balloon for focal stenotic lesions at the femoral bifurcation [64]. In a review of single-center studies evaluating treatment of isolated common femoral artery disease, technical success for endovascular intervention was >90 percent, with one-year primary patency rates ranging from 73 to 81 percent [61]. Stent placement in the common femoral artery is less frequent as a primary intervention, but some data are available to support its use in selected patients [62,63]. In one trial that compared endovascular with surgical intervention for common femoral artery stenosis (no occlusions), morbidity and mortality were significantly lower for stenting (26 versus 12.5 percent), with similar patency and reintervention rates at 24 months follow-up [62].

Femoro-popliteal segment — Indications for superficial femoral artery intervention are unilateral leg claudication meeting the criteria discussed above (see 'Clinical criteria for revascularization' above) and the presence of stenosis or occlusion in the superficial femoral artery or popliteal artery on duplex or cross-sectional imaging. There is usually hemodynamic evidence of impaired distal perfusion at rest, which is often exaggerated by exercise testing.

Endovascular interventions have been widely adopted as the first line of revascularization for the femoro-popliteal segment, and improvements in technology and technical skills in practice have permitted more and more challenging lesions to be tackled [65,66]. This progress can be noted with the changes made in the recommendations for superficial femoral artery occlusive disease between the TASC I [67] and TASC II documents [42]. While the TASC II classification has been widely used for femoro-popliteal lesion complexity, the lesion length as well as involvement of the popliteal artery and the trifurcation vessels also determines the complexity of the disease. (See 'Anatomic classification' above.)

The complexity and length of femoro-popliteal lesions for which endovascular interventions can be performed successfully has increased over the years [8,68,69]. In addition to lesion length and severity of stenosis/occlusion, the amount of calcification is a factor that determines the technical success rate and patency rates of endovascular interventions. Severe calcification is typically observed in patients with diabetes and patients with chronic kidney disease. Other anatomic factors also play a role in deciding between endovascular intervention or open surgical bypass, such as the presence of flush superficial femoral artery occlusions, proximal superficial femoral artery disease, runoff status, and thrombus.

Bypass grafting for femoro-popliteal disease was the mainstay for the treatment of claudication, and most of the data on bypasses come from an era where the threshold for surgical intervention for treating claudication was higher than the current era due to the increasing emphasis on optimal medical management and the introduction of endoluminal techniques. Operative results for infrainguinal occlusive disease were generally quite good [16,70]. Randomized trials and multiple large case series have documented excellent anatomic and functional performance of lower extremity bypasses using venous conduits, albeit with a small but notable mortality and morbidity in the short term. Many series have reported an operative mortality rate of nearly zero in carefully selected patients with claudication (eg, those with low cardiac risk) [16,71-73]. One study examined the results of 409 infrainguinal reconstructions for claudication over a 10-year period [71]. Operative mortality rate was 0 percent, and one limb was lost in the series from distal embolization. The primary patency rates for above-knee popliteal artery and below-knee popliteal artery revascularization at four years were 62 percent and 77 percent, respectively, and secondary patency rates were 64 percent and 81 percent, respectively. Cumulative patient survival at four and six years was 93 percent and 80 percent, respectively, which was significantly higher compared with infrainguinal revascularization performed for limb salvage at 65 percent and 52 percent, respectively. Similarly, a study of over 50 femoro-popliteal bypass grafts for intermittent claudication reported no perioperative mortality, with a single patient requiring below-knee amputation 12 years after the initial procedure [72]. Cumulative graft patency was 93 percent at two years and 88 percent at five years. These patency rates were also superior to collective results of femoro-popliteal graft patency performed for limb salvage [74].

No role for infrapopliteal intervention — Tibial interventions are not considered mainstream for the treatment of intermittent claudication. While infrapopliteal disease with patent femoro-popliteal arteries is not uncommon, particularly in patients with diabetes or chronic kidney disease, infrapopliteal percutaneous intervention for claudication is almost never recommended or performed. Similarly, tibial bypass is not considered an appropriate intervention for claudication.

Although patency after femoro-popliteal intervention has been reported to be improved in patients with two or more runoff vessels, intervening on infrapopliteal arteries for the purpose of improving runoff status in patients having femoro-popliteal interventions has not been studied and is not recommended.

MEASURES OF SUCCESS AND SURVEILLANCE — Patients with claudication commit to a lifelong management for their cardiovascular risk factors, and those who undergo endovascular intervention or surgical bypass are enrolled in a surveillance program where imaging of the intervention and assessment of distal perfusion are undertaken at 6- or 12-month intervals unless new symptoms of claudication occur, in which case prompt reimaging for the intervention should be performed to identify a recurrent lesion (treatment failure) or de novo disease.

Periodic clinical evaluations should note resolution; return or progression of symptoms of claudication; the presence of pulses; measurement of the ankle-brachial pressure index (ABI) at both rest and after exercise, as needed; and duplex imaging of the target lesion in endoluminal interventions or the entire length of the graft and adjacent inflow and outflow arteries to evaluate for graft stenosis [75-77].

The success of revascularization for claudication may be measured anatomically, hemodynamically, or functionally (clinically).

●Anatomically, the patency of the intervention, as defined by the Society for Vascular Surgery (SVS) reporting standards, allows one to assess the time to primary failure (ie, occlusion or need for intervention) and the time to final failure after multiple interventions and revisions [3].

●Hemodynamic success is defined as an increase in ABI of 0.15. Immediate and long-term hemodynamic success (ABI >0.15) after percutaneous transluminal angioplasty (PTA) is directly related to tibial runoff [78]. Most studies have shown an appropriate increase in ABI after PTA. The duration of the increase is unknown and may or may not correlate with symptomatic improvement. When surgery is compared with PTA for lesions appropriate for PTA, there are no significant differences between bypass surgery and PTA [22,23]. Studies of patients after surgery (ie, ilio-femoral or femoro-popliteal bypass) have shown that, at six weeks, there is an improvement in resting ABI and improved treadmill testing [67]. Optimal results appear to be restricted to patients younger than 70 years, patients without diabetes, and in those in whom normal ankle pressure is anticipated based on the lesion corrected and the anatomic distribution of PAD.

●While anatomic patency and hemodynamic success are important, the primary reason to perform an intervention is symptom relief, functional improvement with activities of daily living, and long-term clinical success. One study demonstrated that 40 percent of patients maintain symptom-free status four years after superficial femoral artery angioplasty [79]. The finding that clinical success appears to be higher than anatomic success has been reported by others [79,80]. Up to 20 percent of patients will be dissatisfied with their surgical outcome, even though 50 percent of this dissatisfied subgroup will have a normal postoperative ABI [16]. Similar data are not yet available for PTA of the superficial femoral artery.

APPROACH TO TREATMENT FAILURES

Restenosis/reocclusion — Restenosis and reocclusion are common after lower extremity interventions. A retrospective review examined the long-term outcome following open surgical or endovascular intervention in 233 patients with claudication in which priority in primary treatment was given to endovascular intervention [81]. A mean of two (median, one) operations per limb were performed during follow-up. No additional procedures were needed in 50.3 percent of limbs. Crossover between endovascular and surgical treatment was recorded in 64 (21.1 percent) of limbs. Primary, secondary, and total patency rates were 27, 45, and 61 percent at five years, respectively, and 16, 27, and 41 percent at 10 years, respectively. Chronic limb-threatening ischemia (CLTI) occurred in 37 limbs (12.2 percent), of which 15 (41 percent) had been treated with endovascular methods only. Type II diabetes and hypertension were significant predictors of increased risk for developing CLTI.

An uncomplicated failed endovascular intervention does not generally appear to compromise subsequent surgery and long-term outcomes [82-84]. Functional (clinical) failure is only partially related to anatomic patency of the treated area; other factors such as progression of disease in the inflow vessels, treated vessel, and outflow tract are also implicated. Half of these lesions are amenable to percutaneous intervention.

●For aorto-iliac lesions, when restenosis or occlusion occurs after endovascular intervention, multiple modalities can be used to address the culprit lesion, including clot extraction and lysis, repeat conventional balloon or scoring/cutting balloon angioplasty, and stenting with conventional covered or drug-eluting stents. Ultimately, if these modalities fail, aorto-iliac bypass can be performed in the suitable-risk patient.

●For femoro-popliteal lesions, multiple treatment modalities can be used to address restenosis and occlusion following intervention, including primary thrombolysis with secondary intervention, repeat conventional balloon or cutting balloon angioplasty, stenting with conventional or drug-eluting stents, or the use of atherectomy devices to debulk the lesion [65,66,85].

●For the patient with disabling symptoms following multiple attempts at percutaneous revascularization, surgical bypass should generally be reserved for low-risk patients who can be expected to tolerate the procedure and live long enough to enjoy the improved quality of life. Patients who benefit most from surgical revascularization are generally under 70 years of age, do not have diabetes, and have little evidence of disease distal to the primary lesion [16].

Early failure of endovascular therapy for superficial femoral artery disease is generally not associated with significant morbidity and mortality, and options for surgical bypass are not compromised [83]. However, in one study, early failure after isolated endovascular intervention of the superficial femoral artery altered the distal target in 30 percent if open bypass was planned [82]. Multiple reports have demonstrated that anatomic and technical factors affect the outcomes of superficial femoral artery intervention for claudication [86-96]. In one study, predictors of clinical failure of superficial femoral intervention included [91,92]:

●In the early period (<12 months) – age, superficial femoral artery occlusion, degree of atherosclerosis, and angioplasty technical outcome

●In the immediate period – age, superficial femoral artery lesion length and calcification, superficial femoral artery occlusion, angioplasty technical outcome (ie, residual stenosis, presence of dissection, occlusion), and runoff

●In the late period (>12 months), only angioplasty technical outcome was important

For patients who have undergone lower extremity bypass, 30 percent of vein grafts develop stenotic lesions, and these require either percutaneous intervention for focal lesions or open revision for more extensive lesions. Reintervention for graft stenosis and maintenance of primary assisted patency have better outcomes compared with interventions for graft occlusion and seeking to improve secondary patency. Patient sex, age, indication, the presence of diabetes mellitus or renal disease, and vein graft conduit type do not appear to be predictive of the need for subsequent revision [88]. Bypass grafts that require revision because of early lesions (<6 months from index graft placement) are more likely to require an additional revision procedure [88]. Long-term conduit failure does occur, which may necessitate reintervention. Occlusion of a bypass graft for claudication generally returns the patient to preoperative status unless there has been proximal extension of the thrombus to the ostium of the profunda femoris or distal embolization. Thrombolysis followed by focused revision to the graft has markedly decreased the morbidity of bypass graft revisions. For grafts that continue to fail, sometimes a percutaneous recanalization of the native circulation can be achieved to avoid the need for a new bypass [97,98]. (See "Lower extremity surgical bypass techniques", section on 'Complications' and "Intra-arterial thrombolytic therapy for the management of acute limb ischemia".)

Progression to limb-threatening ischemia — Several studies have reported that revascularization of patients with intermittent claudication is associated with an increased risk for progression of disease and amputation [99-103]. One retrospective review studied all patients at a single institution with an initial diagnosis of intermittent between 2003 and 2019. Among the 1051 identified patients who met the inclusion criteria, 328 had at least one revascularization procedure and 723 did not. Revascularization was associated with a higher risk for progression to CLTI compared with no revascularization (hazard ratio [HR] 2.9, 95% CI 2.0-4.2), and amputation (HR 4.5, 95% CI 2.2-9.5). Such sober findings should be considered in the management of these patients and included in any shared decision-making discussions with the patient. (See 'Clinical criteria for revascularization' above.)

SUMMARY AND RECOMMENDATIONS

●Goals of revascularization – The primary goal of revascularization in patients with peripheral artery disease (PAD) and claudication is functional improvement, taking into consideration the severity of the patient's symptoms and their impact on daily activities and the potential for improvement. The benefits of any proposed revascularization should outweigh the potential risks, which are procedure specific. In addition, the durability of the anticipated revascularization relative to the patients' anticipated life expectancy plays a role. (See 'Clinical criteria for revascularization' above.)

●Revascularization options – Options for revascularization in patients with claudication include endovascular (eg, angioplasty, stenting, atherectomy), open surgical (eg, bypass procedures, endarterectomy), and hybrid approaches (eg, common femoral endarterectomy combined with superficial femoral artery angioplasty/stenting). For appropriate candidates, the level of and options for revascularization are determined through clinical evaluation and vascular imaging. The availability of autologous vein is another determinant for those with femoro-popliteal disease. (See 'Clinical evaluation' above.)

●Advanced vascular imaging – The goal of advanced vascular imaging is to aid selecting and planning intervention. As such, it should never be performed before a clinical decision has been made for revascularization. In most cases, the imaging study of choice is computed tomographic (CT) angiography, which provides information about the level and severity of vascular obstruction (aorto-iliac, femoral, popliteal), luminal diameter, the presence of luminal thrombus, vascular calcification. Other imaging options include magnetic resonance (MR) angiography, and duplex ultrasound. (See 'Vascular assessment and imaging' above.)

●Initial revascularization approach – For patients with claudication due to atherosclerotic disease who are candidates for revascularization and with anatomically suitable lesions, an initial endovascular is preferred, rather than an open surgical approach. Endovascular interventions are associated with fewer periprocedural complications compared with surgical revascularization but higher rates of restenosis, which can usually be managed with repeat endovascular intervention. In general, uncomplicated failed endovascular intervention does not appear to compromise subsequent surgical options or long-term success. (See 'Initial approach' above.)

•When the anatomic location or other anatomic factors are not favorable for an endovascular approach, a surgical approach may be reasonable.

•For patients who are poor surgical candidates, an endovascular approach (even a limited revascularization) may be possible, regardless of anatomic complexity.

•For good-risk patients who are younger, the durability of revascularization may be an important factor favoring a surgical approach; however, for very young patients (<40 years) with early onset atherosclerotic disease, caution should be exercised before proceeding with any revascularization for claudication symptoms because outcomes of revascularization (endovascular or surgical) are poor.

•For patients with combined aorto-iliac and femoro-popliteal disease, the inflow lesion should be addressed first. For persistent claudication symptoms following aorto-iliac revascularization, femoro-popliteal intervention may be warranted.

●Approach to specific lesions – Our approach to specific lesions is as follows:

•For most patients with inflow disease (aorta, aorto-iliac [unilateral, bilateral iliac involvement]) due to PAD, we suggest initial angioplasty and stenting for even the most complex anatomy, rather than open surgical revascularization (eg, aorto-iliac bypass, aortofemoral bypass) (Grade 2C). For patients with significant, concomitant involvement of the common femoral artery, a hybrid approach may be needed with common femoral endarterectomy and patch angioplasty. Surgical aorto-iliac or aortofemoral reconstruction can be offered to good-risk candidates if endovascular intervention has failed or is anticipated to fail (eg, juxtarenal aortic disease, excessive thrombus burden, small or hypoplastic aorta). (See 'Revascularization to restore inflow' above.)

•For most patients with common femoral artery occlusive disease, we suggest common femoral endarterectomy with or without profundaplasty, rather than angioplasty, stenting, atherectomy, or laser interventions (Grade 2C). Common femoral artery endarterectomy is well tolerated and can be performed under local or regional anesthesia and can be combined with proximal or distal endovascular intervention as a hybrid procedure. (See 'Common femoral artery' above.)

•For most patients with superficial femoral and/or popliteal artery disease, we suggest initial endovascular intervention, rather than femoro-popliteal bypass (vein, graft) (Grade 2C). Surgery can be offered to good-risk candidates if endovascular intervention has failed or is anticipated to fail (eg, severe long-segment stenosis/occlusion, distal popliteal disease). When selected, open surgical revascularization has a high cumulative patency with nearly zero perioperative mortality in good-risk surgical candidates. (See 'Femoro-popliteal segment' above.)

●Measures of success and surveillance – Patients with claudication undergo life-long medical management of their cardiovascular risk factors and surveillance of any interventions (endovascular or bypass) to identify a failing intervention that might permit reintervention. Periodic clinical follow-up includes evaluations for return of symptoms, the presence of pulses, and any changes in the ankle-brachial pressure index. For patients who have undergone infrainguinal bypass with autogenous vein conduit, routine duplex surveillance should be performed to evaluate for graft stenosis, which develops in 20 to 30 percent of vein bypass grafts during the first year and can lead to graft failure. Long-term patency rates are improved for vein grafts that are monitored and treated when a significant stenosis is identified. (See 'Measures of success and surveillance' above and "Lower extremity surgical bypass techniques", section on 'Graft surveillance'.)

●Treatment failures – Whether to offer open repeat revascularization for claudication following endovascular failure is individualized. A patient who remains symptomatic despite medical therapy and prior attempts at percutaneous revascularization may be a candidate for surgical revascularization provided anatomy is favorable, conduit is available, and runoff is adequate, and the patient does not have a prohibitive risk for open surgery. (See 'Approach to treatment failures' above.)