Fem-Fem Bypass with Synthetic Conduit is Medically Indicated for This Patient
Yes, femoral-femoral bypass using a synthetic conduit is medically indicated for this patient with severe PVD presenting with rest pain and critical limb-threatening ischemia due to complete left common iliac and near-complete left external iliac artery occlusion that is not amenable to endovascular intervention alone. 1
Clinical Justification
This Patient Meets Clear Indications for Surgical Revascularization
The patient has chronic limb-threatening ischemia (CLI) with rest pain for over 2 years, which is a Class I indication for revascularization to achieve limb salvage. 2
The anatomic pattern—unilateral iliac occlusion with planned contralateral iliac intervention—is the classic scenario for fem-fem bypass. 1 The ACC/AHA guidelines specifically describe this procedure: blood flows from the donor femoral artery (right side, which will receive CIA shockwave treatment and stenting to optimize inflow) to the recipient femoral artery (left side with complete occlusion). 1
Endovascular therapy has already been deemed inadequate (imaging showed disease "not stentable"), making surgical bypass the appropriate next step rather than a premature intervention. 2
Fem-Fem Bypass Patency is Acceptable for This Indication
For unilateral iliac occlusion without donor limb disease, fem-fem bypass achieves 73% patency at 1 year and 59% patency at 5-7 years. 1 While this is lower than aortobifemoral bypass (85.8% at 5 years), it is substantially better than axillofemoral bypass (47% at 5 years). 1
The planned right CIA intervention with VBX stenting will optimize inflow to the donor limb, which is critical for fem-fem bypass success—the guidelines emphasize that patency rates of 78-92% at 1 year and 66% at 7 years are achievable when there is no donor limb disease. 1
Synthetic Conduit is Appropriate for This Anatomic Location
Synthetic grafts (PTFE or polyester) are acceptable for fem-fem bypass at the iliac/femoral level. 1 The guidelines reserve the strong preference for autogenous vein specifically for infrainguinal bypasses (fem-popliteal and fem-tibial). 1, 2
Above-knee prosthetic grafts achieve 47-50% patency at 5 years, which is acceptable when vein is not available or when the anatomic location (iliac-femoral) makes synthetic material reasonable. 3
The synthetic conduit for fem-fem bypass avoids crossing the knee joint, where prosthetic graft performance deteriorates significantly (dropping to 33% at 5 years for below-knee locations). 3
Critical Pitfalls to Avoid
Ensure adequate inflow from the donor (right) limb before or during the fem-fem bypass. 2 The planned right CIA shockwave treatment with VBX stenting must successfully address the "severe stenosis" to prevent early graft failure. The guidelines are explicit: "inflow lesions should be addressed first before considering fem-pop bypass." 2
Do not delay revascularization in this patient with rest pain. 2 Unlike claudication (where conservative management is mandatory first), CLI with rest pain requires urgent intervention to prevent limb loss—without successful revascularization, patients with critical ischemia have an 80-90% amputation rate within one year. 4
The 1-day bed stay is appropriate for uncomplicated fem-fem bypass, which is less invasive than aortobifemoral reconstruction and can be performed under regional or even local anesthesia in selected cases. 1
Why Alternative Approaches Are Inferior
Aortobifemoral bypass would be more durable (85.8% patency at 5 years) but carries higher operative mortality (1.3-6.3%) and morbidity. 1 Given this patient's active tobacco use and likely cardiopulmonary comorbidities, the less invasive fem-fem approach is more appropriate.
Axillofemoral bypass is reserved only when there are no alternatives, with significantly inferior patency (19-50% at 5 years for axillofemoral, 50-76% for axillobifemoral). 1
Endovascular-only approaches have already been excluded by the treating team's assessment that the disease is "not stentable" with complete left common iliac occlusion. 4