Overview

Definition:
-Popliteal artery endarterectomy with patch angioplasty is a surgical procedure to remove atherosclerotic plaque from the popliteal artery and reconstruct the vessel wall using a patch graft
-It is employed to restore blood flow to the lower limb in cases of significant stenosis or occlusion
-This procedure aims to preserve the native artery and avoid limb amputation.
Epidemiology:
-Peripheral Artery Disease (PAD) affects a significant portion of the elderly population, with the infrainguinal arteries, including the popliteal artery, being commonly involved
-Risk factors include advanced age, smoking, diabetes mellitus, hypertension, and hyperlipidemia
-The prevalence of critical limb ischemia requiring intervention is substantial.
Clinical Significance:
-Successful revascularization of the popliteal artery is crucial for managing limb-threatening ischemia
-Popliteal endarterectomy with patch angioplasty offers a limb salvage option when angioplasty alone is not sufficient or when the disease pattern is amenable to open surgical reconstruction
-It is a vital procedure for surgical residents preparing for DNB and NEET SS examinations.

Indications

Surgical Indications:
-Significant stenosis (>50%) or occlusion of the popliteal artery
-Symptomatic limb ischemia (Rutherford classification 3-6), including claudication, rest pain, and non-healing ulcers or gangrene
-Patients with unfavorable anatomy for endovascular intervention or those who have failed previous endovascular treatments
-Absence of significant distal disease that would preclude successful revascularization.
Patient Selection:
-Careful patient selection is paramount
-Factors to consider include comorbidities, life expectancy, and the patient's ability to tolerate surgery
-Assessment of the distal vascular tree is essential to ensure run-off after popliteal reconstruction.
Disease Pattern:
-Favorable disease patterns for endarterectomy include focal atherosclerotic disease in the popliteal artery, particularly with ostial involvement or tandem lesions
-Disease that is not excessively calcified or tortuous is also ideal.

Preoperative Preparation

History And Physical:
-Detailed history of symptoms, duration, and progression
-Assessment of risk factors for PAD
-Comprehensive physical examination including pulse examination in all extremities, assessment for signs of ischemia (e.g., dependent rubor, pallor on elevation), and evaluation of wounds or ulcers.
Investigations:
-Ankle-Brachial Index (ABI) and segmental limb pressures
-Duplex ultrasonography to assess the extent and severity of arterial stenosis or occlusion
-Computed Tomography Angiography (CTA) or Magnetic Resonance Angiography (MRA) to delineate the anatomy and plan the surgical approach
-Routine laboratory investigations including complete blood count, renal function tests, coagulation profile, and electrocardiogram.
Anesthesia And Consent:
-General or regional anesthesia (e.g., spinal or epidural anesthesia) may be used
-Informed consent must be obtained, detailing the procedure, potential risks, benefits, and alternatives.

Procedure Steps

Exposure:
-A surgical incision is made, typically a medial or posteromedial approach to the popliteal fossa, to expose the popliteal artery and its branches
-Careful dissection is performed to identify the artery and surrounding structures.
Arterial Control And Isolation:
-The popliteal artery proximal and distal to the diseased segment is identified and carefully isolated
-Temporary vascular clamps are applied proximal and distal to the target segment to control blood flow.
Endarterectomy:
-An arteriotomy is made longitudinally over the occluded or stenotic segment of the popliteal artery
-Atherosclerotic plaque is carefully dissected and removed from the arterial wall using specialized instruments, ensuring a smooth intima distally and proximally
-The aim is to achieve a plane between the plaque and the media of the artery.
Patch Angioplasty:
-Following plaque removal, the arteriotomy is closed with a vascular patch
-Common patch materials include autologous saphenous vein, synthetic materials (e.g., Dacron, PTFE), or bovine pericardium
-The patch is sutured in place using fine vascular sutures to reconstruct the arterial lumen and prevent narrowing.
Completion Angiography:
-After reconstruction, a completion angiogram is often performed to assess the patency of the repaired segment, ensure adequate flow, and identify any residual stenosis or technical complications
-Flow is then restored by releasing the clamps
-Hemostasis is achieved.

Postoperative Care

Monitoring:
-Close monitoring of vital signs, limb perfusion (color, temperature, capillary refill, Doppler signals), and fluid balance
-Early ambulation is encouraged as tolerated.
Antithrombotic Therapy:
-Anticoagulation (e.g., heparin) may be continued postoperatively
-Aspirin and/or clopidogrel are typically initiated to prevent graft thrombosis
-Long-term antiplatelet therapy is usually recommended.
Wound Care:
-Routine wound care to prevent infection
-Pain management as required.
Follow Up Assessment: Regular clinical and duplex ultrasound follow-up examinations are crucial to monitor the patency of the repaired artery and the development of any complications.

Complications

Early Complications:
-Graft thrombosis (acute occlusion)
-Bleeding from the arteriotomy or patch site
-Wound infection
-Deep vein thrombosis (DVT)
-Nerve injury (e.g., peroneal nerve dysfunction causing foot drop)
-Compartment syndrome
-Pseudoaneurysm formation at the suture lines.
Late Complications:
-Graft stenosis or occlusion due to intimal hyperplasia or recurrent atherosclerosis
-Infection of a synthetic graft
-Distal embolization
-Progression of disease in other arterial segments.
Prevention Strategies:
-Meticulous surgical technique, judicious use of anticoagulation and antiplatelet therapy, careful wound closure, and early mobilization
-Comprehensive preoperative risk factor management
-Serial duplex surveillance to detect early signs of graft failure.

Prognosis

Factors Affecting Prognosis:
-The extent and severity of PAD, presence of comorbidities (diabetes, renal failure), quality of run-off, and adherence to postoperative medical therapy significantly influence prognosis
-Successful revascularization typically leads to symptom improvement and limb salvage.
Outcomes:
-Popliteal artery endarterectomy with patch angioplasty has demonstrated good long-term patency rates and limb salvage, particularly in carefully selected patients
-Amputation-free survival rates are generally favorable, often exceeding those of distal bypass procedures in specific cases.
Follow Up:
-Lifelong follow-up is recommended, with regular clinical assessments and non-invasive vascular studies to monitor graft patency and the progression of PAD
-Management of risk factors should be continuous.

Key Points

Exam Focus:
-Understand the indications for popliteal endarterectomy over bypass or angioplasty
-Recognize the importance of distal run-off
-Master the steps of endarterectomy and patch reconstruction
-Know the common early and late complications and their management.
Clinical Pearls:
-Thorough intraoperative assessment of plaque removal and intima smoothness is critical
-Careful handling of surrounding nerves, especially the peroneal nerve, can prevent foot drop
-Consider the use of an autologous vein patch when possible to minimize infection risk.
Common Mistakes:
-Inadequate plaque clearance leading to residual stenosis
-Insufficient distal dissection and reconstruction
-Poorly placed vascular clamps leading to intimal injury
-Failure to recognize or manage distal embolization
-Neglecting postoperative antithrombotic therapy.