Overview
Definition:
Hybrid iliac artery stenting refers to a combined endovascular and open surgical approach to treat complex iliac artery occlusive disease
It leverages the advantages of both techniques to achieve optimal revascularization, particularly in cases of extensive or challenging lesions where a purely endovascular or open approach might be suboptimal
This can involve performing an open surgical procedure on one limb while an endovascular stent is deployed in the contralateral iliac artery, or a combination of open and endovascular techniques within the same iliac system.
Epidemiology:
Iliac artery occlusive disease affects a significant proportion of patients with peripheral artery disease (PAD), with prevalence increasing with age and risk factors like smoking, diabetes, and hypertension
Complex lesions, including those with significant calcification, long occlusions, or tortuosity, are more common in older populations and may necessitate hybrid techniques
The incidence of iliac interventions has been rising with the widespread adoption of endovascular therapies.
Clinical Significance:
Iliac artery stenting, especially when utilizing a hybrid approach, is crucial for restoring blood flow to the lower extremities, alleviating symptoms of claudication and critical limb ischemia (CLI)
It can prevent amputations, improve quality of life, and reduce cardiovascular morbidity and mortality associated with advanced PAD
For DNB and NEET SS examinations, understanding the indications, contraindications, technical nuances, and potential complications of hybrid techniques is essential for residents preparing for vascular surgery scenarios.
Indications
Indications For Hybrid Approach:
Complex iliac artery lesions that are not amenable to a purely endovascular or open approach
This includes severe calcification making endovascular crossing or stent deployment difficult
Tortuous anatomy that poses a risk for endovascular device manipulation
Long-segment occlusions requiring extensive stenting
Absence of suitable femoral access for endovascular intervention
Patients with significant comorbidities that limit the feasibility of extensive open surgery
Bilateral iliac occlusive disease where staged or concurrent hybrid interventions are planned.
Contraindications:
Active systemic infection
Severe coagulopathy
Life expectancy less than 6 months
Uncorrectable allergy to contrast media
Absence of target inflow or outflow vessels for surgical bypass if needed
Patients who are poor surgical candidates for even limited open procedures.
Patient Selection:
Careful patient selection is paramount
Multidisciplinary team assessment including vascular surgeons, interventional radiologists, and anesthesiologists is often beneficial
Preoperative imaging, particularly CT angiography, is critical for detailed anatomical assessment and planning of the hybrid strategy
Risk stratification using tools like the ACS-NSQIP calculator is important.
Diagnostic Approach
History Taking:
Detailed history focusing on claudication symptoms (location, severity, duration, aggravating/relieving factors)
Assessment for rest pain, non-healing ulcers, or previous amputations indicating CLI
Past medical history including cardiovascular risk factors (hypertension, diabetes, hyperlipidemia, smoking, family history)
Previous vascular interventions or surgeries
Review of medications, especially anticoagulants and antiplatelets.
Physical Examination:
Palpation of peripheral pulses (femoral, popliteal, dorsalis pedis, posterior tibial) with grading
Auscultation for bruits over the iliac and femoral arteries
Examination of the lower extremities for skin changes (pallor, cyanosis, atrophy, hair loss), trophic changes, presence of ulcers, and temperature differences
Assessment of neurological status.
Imaging Investigations:
Ankle-brachial index (ABI) to screen for PAD
Duplex ultrasound to assess arterial anatomy and flow
Computed tomography angiography (CTA) is the gold standard for detailed anatomical assessment, including lesion length, severity, calcification, tortuosity, and relationship to surrounding structures
Magnetic resonance angiography (MRA) can be an alternative, especially in patients with contrast allergies or renal insufficiency
Conventional angiography may be performed intraoperatively for planning and execution.
Differential Diagnosis:
Other causes of leg pain such as musculoskeletal disorders (osteoarthritis, spinal stenosis), neuropathic pain (diabetic neuropathy), venous insufficiency, and superficial thrombophlebitis.
Management
Preoperative Preparation:
Optimization of cardiovascular risk factors (blood pressure, glycemic control)
Administration of antiplatelet therapy (e.g., aspirin, clopidogrel) preoperatively
Antibiotic prophylaxis as per institutional guidelines
Anesthesia planning based on patient comorbidities and extent of surgery
Fluid management and electrolyte balance correction.
Hybrid Procedure Techniques:
The specific hybrid technique depends on the anatomy and surgeon's preference
Common strategies include: Ipsilateral open femorofemoral bypass with contralateral iliac stenting
Ipsilateral iliac endarterectomy/patch angioplasty with contralateral iliac stenting
Transatlantic bypass with contralateral iliac stenting
Open proximal control of the iliac artery with antegrade deployment of a stent distally, followed by open repair of the arteriotomy
Staged procedures: initial endovascular stenting of one iliac artery, followed by open or endovascular intervention on the contralateral side.
Endovascular Component:
Includes guidewire crossing of the lesion, angioplasty, stent selection (bare metal vs
drug-eluting, diameter, length), stent deployment, and post-stent angioplasty
Embolization protection devices may be used
Accurate imaging guidance is crucial.
Open Surgical Component:
May involve arteriotomy and primary repair, endarterectomy, or bypass grafting (e.g., femorofemoral bypass)
Careful surgical technique to minimize bleeding and ensure adequate wound healing is essential.
Postoperative Care:
Close monitoring of vital signs and hemodynamic status
Pain management
Wound care to prevent infection and ensure healing
Anticoagulation and antiplatelet therapy is crucial
typically dual antiplatelet therapy (DAPT) for a specified period followed by single antiplatelet therapy indefinitely
Monitoring for neurological deficits and limb perfusion
Early ambulation as tolerated.
Complications
Early Complications:
Bleeding from access sites (surgical or endovascular)
Hematoma formation
Pseudoaneurysm at access sites
Vessel dissection or perforation
Stent malapposition, migration, or fracture
Limb ischemia due to embolization or thrombosis
Myocardial infarction or stroke
Allergic reaction to contrast or medications
Infection.
Late Complications:
Stent restenosis due to neointimal hyperplasia or thrombosis
Endograft infection (if applicable)
Chronic limb ischemia due to graft failure or non-healing lesions
Aneurysm formation distal to the stent
Chronic pain
Incisional hernia at surgical access sites.
Prevention Strategies:
Meticulous surgical technique and appropriate patient selection
Careful imaging for lesion characterization and planning
Use of appropriate guidewires, catheters, and stent devices
Adjunctive angioplasty and post-stent dilation
Adequate anticoagulation and antiplatelet therapy post-procedure
Comprehensive wound care and infection prophylaxis
Close follow-up with regular imaging.
Prognosis
Factors Affecting Prognosis:
Severity of PAD at presentation
Presence of critical limb ischemia
Comorbidities (e.g., diabetes, renal insufficiency, CAD)
Success of the revascularization procedure (angiographic and clinical)
Adherence to antiplatelet therapy
Quality of inflow and outflow vessels
Technical success of the hybrid intervention.
Outcomes:
Successful hybrid iliac stenting generally leads to significant improvement in symptoms, wound healing, and limb salvage rates
Patency rates for iliac stents are generally high, particularly for shorter lesions and with appropriate antiplatelet therapy
Long-term outcomes are influenced by the progression of PAD in other arterial segments and overall cardiovascular health.
Follow Up:
Regular clinical follow-up is essential, typically at 1 month, 6 months, and annually thereafter
Duplex ultrasound surveillance is recommended to monitor stent patency and detect any signs of restenosis or complications
Interval imaging with CTA or MRA may be indicated based on clinical suspicion of recurrence or complications
Patients should be educated on lifestyle modifications, risk factor management, and adherence to medication.
Key Points
Exam Focus:
Understand the definition and rationale behind hybrid approaches for complex iliac lesions
Differentiate indications from contraindications
Know the common combinations of open and endovascular techniques
Recognize early and late complications specific to hybrid interventions
Recall the importance of dual antiplatelet therapy.
Clinical Pearls:
Always obtain high-quality pre-procedural CTA for detailed anatomical assessment
Consider crossing severely calcified lesions with hydrophilic wires after balloon angioplasty
Use a stent graft for common iliac artery aneurysms or dissections
Coordinate care between surgical and interventional teams for optimal outcomes
Adequate proximal and distal landing zones are critical for stent deployment.
Common Mistakes:
Underestimating the complexity of the lesion and opting for a purely endovascular approach when hybrid is indicated
Inadequate preoperative imaging leading to intraoperative surprises
Poor access site management, leading to bleeding or pseudoaneurysm
Premature discontinuation of dual antiplatelet therapy
Insufficient follow-up leading to missed restenosis or complications.