Overview
Definition:
A femoro-femoral crossover bypass is a surgical procedure used to treat aortoiliac occlusive disease or unilateral iliac artery stenosis
It involves creating a conduit from one common femoral artery to the contralateral common femoral artery, bypassing the occluded or stenotic iliac segment.
Epidemiology:
Peripheral artery disease (PAD) affects approximately 200 million people worldwide
Aortoiliac occlusive disease (Leriche syndrome) accounts for about 10-15% of PAD cases
Femoro-femoral bypass is a common reconstructive option for select patients with unilateral iliac occlusive disease or when aortoiliac reconstruction is not feasible.
Clinical Significance:
This bypass is a critical intervention for limb salvage and symptom relief in patients with severe iliac artery disease causing claudication or critical limb ischemia
It offers a less invasive alternative to abdominal aortic surgery in appropriately selected patients, preserving antegrade flow to the lower extremities.
Indications
Indications:
Unilateral iliac artery occlusion or severe stenosis with symptoms of limb ischemia
Leriche syndrome (aortoiliac occlusion) in patients unsuitable for aortoiliac reconstruction
Distal embolization from an iliac artery aneurysm
As a limb salvage procedure in the presence of contralateral common femoral artery patent.
Contraindications:
Severe bilateral iliac artery occlusive disease requiring aortoiliac reconstruction
Infection at the groin or operative site
Significant cardiopulmonary disease precluding major surgery
Absence of a patent contralateral common femoral artery
Uncontrolled systemic disease.
Preoperative Preparation
History And Physical:
Detailed history of claudication, rest pain, ischemic ulcers, or gangrene
Assessment of risk factors for PAD (smoking, diabetes, hypertension, hyperlipidemia)
Physical examination for pulse deficits, bruits, skin changes, and signs of ischemia
Evaluate pulses in both groins and distal to them.
Imaging Studies:
Duplex ultrasound to assess arterial anatomy and severity of stenosis/occlusion
CT angiography (CTA) or MR angiography (MRA) to delineate the extent of disease, anatomy of the iliac and femoral arteries, and identify suitable inflow and outflow vessels
Conventional angiography if imaging is equivocal or for pre-operative planning.
Medical Optimization:
Cardiopulmonary assessment and optimization
Management of comorbidities like diabetes, hypertension, and renal insufficiency
Smoking cessation counseling
Preoperative antibiotics as per institutional protocol
Anesthesia consultation.
Procedure Steps
Incisions:
Bilateral inguinal incisions are made to expose the common femoral arteries
The proximal extent of the disease is identified, and the contralateral common femoral artery is also prepared.
Graft Selection:
Autologous saphenous vein (reversed or in situ) is the preferred conduit when available
If vein is unavailable or inadequate, prosthetic grafts (e.g., PTFE) are used
The length of the graft should be sufficient to reach comfortably from the inflow to the outflow femoral artery.
Anastomosis Creation:
The inflow anastomosis is typically created end-to-side to the common femoral artery on the side with the less severe iliac disease or the patent iliac artery
The outflow anastomosis is created end-to-side to the common femoral artery on the occluded or stenotic side
Careful attention is paid to angulation to avoid kinking.
Graft Passage:
The graft is tunneled subcutaneously across the lower abdomen, typically in the midline or slightly paramedian, from the inflow side to the outflow side
The tunnel must be wide enough to prevent compression of the graft.
Completion Angiography:
Intraoperative angiography is performed to confirm patency of the graft, assess the anastomoses, and identify any residual stenoses or kinks
Artery-on-artery flow is confirmed.
Postoperative Care
Monitoring:
Close monitoring of graft patency by palpating distal pulses and observing limb perfusion
Doppler ultrasound assessment of graft flow
Continuous cardiac and hemodynamic monitoring
Strict fluid management.
Pain Management:
Adequate analgesia to ensure patient comfort and facilitate early ambulation
Epidural or patient-controlled analgesia may be employed.
Wound Care:
Routine wound care to prevent infection
Early mobilization to reduce risk of DVT and PE
Graduated compression stockings may be used.
Medical Therapy:
Initiation or continuation of antiplatelet therapy (e.g., aspirin, clopidogrel) to maintain graft patency
Statins are prescribed for lipid management
Antihypertensives and glycemic control are maintained
Patients are advised on lifestyle modifications, including smoking cessation.
Complications
Early Complications:
Graft thrombosis (most common early complication)
Bleeding from anastomoses
Wound infection
Lymphocele
Acute limb ischemia due to graft occlusion or embolization
Myocardial infarction or stroke
Deep vein thrombosis (DVT) and pulmonary embolism (PE).
Late Complications:
Graft occlusion
Pseudoaneurysm formation at anastomoses
Stenosis at the anastomoses or within the graft
Distal embolization
Chronic wound issues
Graft infection (rare but serious).
Prevention Strategies:
Meticulous surgical technique to ensure good inflow and outflow, proper graft handling, and avoidance of kinks
Careful patient selection and optimization
Aggressive antiplatelet therapy postoperatively
Early detection and management of complications
Regular duplex ultrasound surveillance.
Prognosis
Factors Affecting Prognosis:
Graft patency rates are influenced by the quality of inflow and outflow vessels, the type of graft material used (vein grafts generally have better long-term patency than synthetic grafts), adherence to antiplatelet therapy, and management of risk factors
Patient comorbidities also play a significant role.
Outcomes:
Five-year primary patency rates for femoro-femoral bypass can range from 70-90% for vein grafts and 50-70% for PTFE grafts
Limb salvage rates are high, often exceeding 90%
Symptomatic relief is usually significant, with improvement or resolution of claudication and healing of ischemic lesions.
Follow Up:
Regular clinical follow-up with physical examination and non-invasive vascular studies (e.g., duplex ultrasound) is crucial
Typically, follow-up is scheduled at 1 month, 6 months, and then annually
Surveillance aims to detect early graft failure or complications
Patients should be educated on the importance of lifelong medical management and risk factor control.
Key Points
Exam Focus:
Understand the indications for fem-fem bypass versus aortoiliac reconstruction
Recall the preferred graft material (autologous vein) and alternatives (PTFE)
Identify common early (thrombosis) and late (occlusion, pseudoaneurysm) complications
Recognize the importance of antiplatelet therapy for graft patency.
Clinical Pearls:
Ensure adequate exposure of both common femoral arteries
Tunnel the graft carefully to avoid compression
Intraoperative angiography is essential for immediate assessment
Lifelong antiplatelet therapy is paramount for long-term success
Consider fem-fem bypass for isolated unilateral iliac disease with a patent contralateral CFA.
Common Mistakes:
Performing fem-fem bypass for extensive bilateral disease requiring aortoiliac reconstruction
Inadequate graft length leading to kinking
Poor control of comorbidities
Discontinuation of antiplatelet therapy
Failure to adequately assess outflow in the recipient limb.