How should a 70–80% stenosis of the superficial femoral artery be managed?

Management of 70-80% Superficial Femoral Artery Stenosis

For a 70-80% stenosis of the superficial femoral artery, begin with at least 3 months of optimal medical therapy (antiplatelet agent, high-dose statin, blood pressure control) combined with supervised exercise therapy before considering any revascularization, unless the patient presents with chronic limb-threatening ischemia or acute limb ischemia. 1, 2

Initial Conservative Management (First-Line for Claudication)

Medical Therapy

• Initiate aspirin 75-325 mg daily to reduce major adverse cardiac events and cardiovascular mortality 1
• Prescribe high-dose statin therapy regardless of lipid levels, as statins improve walking distance beyond cardiovascular risk reduction 1
• Optimize blood pressure control with antihypertensive therapy to reduce stroke, myocardial infarction, heart failure, and cardiovascular death 1
• Achieve glycemic control in diabetic patients 1
• Counsel on tobacco cessation in all patients 3

Supervised Exercise Therapy

• Prescribe supervised exercise training for at least 3 months consisting of at least 30 minutes, at least three times weekly for a minimum of 12 weeks 1, 2
• Supervised exercise therapy alone demonstrates lower 5-year mortality compared to revascularization for intermittent claudication 1
• If supervised exercise is unavailable, recommend non-supervised exercise training 1

When to Consider Revascularization

Absolute Indications (Proceed Directly to Revascularization)

• Chronic limb-threatening ischemia (rest pain, tissue loss, gangrene) 1
• Acute limb ischemia with neurological deficit 1

Relative Indications (After Failed Conservative Management)

• Lifestyle-limiting claudication despite 3+ months of optimal medical therapy and supervised exercise 1, 2, 4
• Quality of life remains significantly impaired after completing conservative therapy 2

Critical Pitfall to Avoid

Do not perform revascularization solely to prevent progression to chronic limb-threatening ischemia - this approach is not supported by evidence and may be harmful 2, 4

Revascularization Strategy Selection

Endovascular Approach (First-Line When Revascularization Indicated)

Primary self-expanding nitinol stenting is the first-line endovascular treatment for intermediate-length superficial femoral artery lesions, demonstrating 20-30% lower restenosis rates at 1-2 years compared with angioplasty alone 3, 1, 4

Technical Considerations

• Self-expandable nitinol stents are preferred due to lower risk of dissection and elastic recoil 1
• Modern long nitinol stents (up to 20 cm) offer improved fracture resistance 3
• The decision to stent is based on clinical indication, lesion length, and complexity 3, 4
• In critical limb-threatening ischemia, stenting can be applied more liberally for limb salvage and ulcer healing 3

Expected Outcomes

• Primary patency rates at 12,24, and 36 months are approximately 73%, 63%, and 54% respectively 5
• Secondary patency rates at 12,24, and 36 months are approximately 85%, 72%, and 72% respectively 5

Alternative Endovascular Options

• Covered stents (stent grafts) are viable options for complex superficial femoral artery lesions with outcomes comparable to prosthetic bypass 3, 1
• Drug-eluting balloons show improved short-term patency rates compared with plain balloon angioplasty 3

Surgical Bypass (When Endovascular Fails or Specific Conditions Met)

Reserve surgical revascularization for patients who fail endovascular therapy, have favorable arterial anatomy, acceptable perioperative risk, autologous vein available, and life expectancy exceeding 2 years 1, 4

Surgical Technique

• Autologous saphenous vein is the conduit of choice for femoropopliteal bypass, demonstrating superior primary patency rates compared with prosthetic graft material 3, 1, 4
• Femoral-above knee popliteal vein bypass: 66% patency at 5 years 3
• Femoral-above knee popliteal prosthetic: 50% patency at 5 years 3
• Do not use femoral-tibial artery bypasses with prosthetic graft material for claudication due to lower patency rates (25% at 3 years) and higher complication risk 3, 4

Factors Predicting Worse Outcomes

Expect diminished long-term patency with the following factors:

• Greater lesion length (>10 cm) 5, 6
• Occlusion rather than stenosis 2
• Multiple diffuse lesions 2
• Poor runoff 2
• Diabetes 2
• Chronic kidney disease 2
• Active smoking 2

Post-Revascularization Management

Surveillance and Medical Therapy

• Continue antiplatelet therapy indefinitely after revascularization 1
• Maintain all components of best medical management including statins, antihypertensives, and glucose control 1
• Implement duplex surveillance program for early detection of restenosis 5

Management of Complications

• For in-stent restenosis, balloon angioplasty alone has very high failure rates - consider repeat stenting for recurrent stenosis 3, 2, 4
• Stent fracture risk factors include number and length of implanted stents, overlapping stents, calcification amount, and deployment technique 3, 4

Important Caveats

• 20-30% of patients may experience persistent symptoms despite patent stents, highlighting the need for careful patient selection and realistic expectations 2, 4
• Do not perform revascularization in asymptomatic patients or those with mild claudication responsive to medical therapy, as surgical interventions carry greater risk of adverse perioperative events 1, 2
• Concomitant iliac stenosis should be addressed at the time of superficial femoral artery intervention, as untreated stenotic superficial femoral artery is a predictor of iliac intervention failure 3