How does the procedure for treating infrapopliteal disease work?

Revascularization Procedures for Infrapopliteal Disease

Infrapopliteal revascularization is primarily reserved for critical limb-threatening ischemia (CLTI) rather than claudication, utilizing either endovascular techniques (balloon angioplasty with or without stenting) or surgical bypass with autogenous vein, depending on lesion characteristics and patient factors. 1

Clinical Context and Patient Selection

Treatment of isolated infrapopliteal disease is typically reserved for patients with CLTI presenting with rest pain, nonhealing wounds, or gangrene—not for claudication. 1 Isolated infrapopliteal disease is an uncommon cause of claudication, and the effectiveness of revascularization for claudication in this setting is unknown due to lack of randomized controlled trials. 1

• Revascularization should NOT be performed for claudication due to isolated infrapopliteal disease, as progression to CLI occurs in only 10-15% over 5 years and procedural risks outweigh hypothetical benefits. 2
• The long-term patency of infrapopliteal procedures is lower than aortoiliac or femoropopliteal interventions, making short-term patency sufficient for wound healing in CLTI the primary goal. 1

Endovascular Approach: Technical Execution

Pre-Procedural Assessment

Complete digital subtraction angiography (DSA) down to the plantar arches is mandatory to properly assess the arterial network and plan the intervention. 1, 3 This includes evaluation of inflow vessels, target lesion characteristics (length, calcification, thrombosis), and outflow to the foot. 1, 3

Procedural Technique

Balloon angioplasty remains the mainstay of endovascular therapy for infrapopliteal lesions. 4 The mechanism involves adventitial stretching, medial necrosis, and controlled dissection or plaque fracture. 4

Key technical principles include: 4

• Careful assessment of vessel calcification before intervention
• Appropriate vessel sizing to avoid oversizing
• Use of long balloons with prolonged inflation times (typically 2-3 minutes)
• Acceptance that some dissection is part of the mechanism of action

Atherectomy can be used for plaque removal in tibial vessels to improve luminal gain before angioplasty, though it carries risk of distal embolization and perforation. 3, 5 Technical success rates are approximately 90% for both angioplasty and atherectomy approaches. 5

Stenting Considerations

Drug-eluting stents demonstrate better patency than bare-metal stents in infrapopliteal arteries when stenting is required. 2 However, stenting should be reserved for specific indications rather than routine use:

• Significant residual stenosis after angioplasty 3
• Flow-limiting dissection 3
• Elastic recoil 3

Plain balloon angioplasty without stenting is preferred for short stenoses (<10 cm) when adequate angioplasty results can be achieved. 1

Establishing In-Line Flow

The primary goal is establishing direct in-line blood flow to the foot through at least one patent infrapopliteal artery. 1, 6 This is essential for wound healing in patients with nonhealing wounds or gangrene. 1

The angiosome concept (targeting the specific artery perfusing the wound area) may be reasonable but requires longer procedural times and more contrast exposure without definitive evidence of superiority over simple in-line flow establishment. 1

Surgical Bypass Approach

Bypass to infrapopliteal vessels using autogenous vein is the gold standard for CLTI when surgical revascularization is chosen. 1

Conduit Selection

Autogenous saphenous vein is strongly recommended over prosthetic graft material (Class I, Level A recommendation). 1 The ipsilateral greater saphenous vein is preferred; if unavailable, use contralateral leg or arm veins. 2

Surgical Technique

• The bypass should be as short as possible while achieving adequate inflow and outflow. 1
• Direct anastomosis to tibial or pedal arteries is performed to establish in-line flow to the foot. 1
• The procedure is performed under general or regional anesthesia. 1

Expected Outcomes

Surgical bypass provides superior long-term patency compared to endovascular approaches, particularly for long occlusions of crural arteries. 1, 7 However, registry data shows infrainguinal bypass to infrapopliteal vessels carries higher perioperative complications and major adverse limb events at 1 year compared to popliteal artery bypass. 1

Treatment Algorithm: Choosing Between Approaches

Favor Endovascular Approach When: 1, 2

• Short stenoses or occlusions are present
• Patient has high surgical risk
• No suitable autogenous vein conduit is available
• Previous radiation therapy or surgery to the local area
• Severe obesity compromising wound healing

Favor Surgical Bypass When: 1, 2

• Long occlusions of crural arteries exist
• Suitable saphenous vein is available
• Acceptable surgical risk
• Need for superior long-term patency

Staged Approach for Multilevel Disease

When both inflow and outflow disease are present, address inflow lesions first. 1, 3 Outflow lesions can be addressed in the same setting or later if symptoms persist. 1 This staged approach is reasonable for ischemic rest pain but differs from CLTI with nonhealing wounds, where direct in-line flow to the foot is immediately essential. 1

Post-Procedural Management

Antiplatelet therapy must be initiated immediately and continued indefinitely after revascularization (Class I, Level A). 2, 3 This improves patency and reduces amputation rates. 3

Regular surveillance with duplex ultrasound is recommended to monitor patency and detect restenosis early. 3

Supervised exercise therapy after intervention improves outcomes beyond the revascularization procedure alone. 3

Critical Pitfalls to Avoid

Do not perform prophylactic revascularization for asymptomatic PAD or claudication to prevent CLI progression—procedural risks outweigh hypothetical benefits. 2

Preserve landing zones for potential bypass grafts when choosing an endovascular-first approach, as subsequent surgical options may be needed. 1, 2

Avoid bare-metal stents in infrapopliteal arteries due to high restenosis rates; use drug-eluting stents if stenting is necessary. 2

Do not compromise profunda femoris artery collaterals during common femoral artery interventions, as these may be critical for limb perfusion. 1

Expected Clinical Outcomes

At 3-month follow-up, endovascular revascularization achieves approximately 71% successful vessel recanalization, 59% linear flow to the foot, and 97% limb salvage. 6 Wound healing or clinical improvement occurs in approximately 56% of patients. 6

At 6 months, limb salvage is 81% and freedom from reintervention is 68%, with similar outcomes between angioplasty and atherectomy approaches. 5

Both surgical and endovascular approaches achieve approximately 80% limb salvage at 3 years, though patency rates favor surgical bypass. 7