What are the indications and considerations for using an Endocraft (endovascular graft) in adults with abdominal aortic aneurysms and a history of vascular disease, such as smoking, hypertension, or peripheral artery disease?

Endovascular Grafts (EVAR) for Abdominal Aortic Aneurysms

In adults with abdominal aortic aneurysms and vascular disease risk factors (smoking, hypertension, peripheral artery disease), endovascular repair (EVAR) should be considered as the preferred therapy when the AAA diameter is ≥55 mm in men or ≥50 mm in women, provided the anatomy is suitable and life expectancy exceeds 2 years. 1

Primary Indications for EVAR

Size-based criteria:

• Elective repair is indicated when AAA diameter reaches ≥55 mm in men or ≥50 mm in women 1, 2
• Intervention may be considered for rapid growth (≥5 mm in 6 months or ≥10 mm per year) regardless of absolute diameter 1, 2
• Saccular aneurysms ≥45 mm may warrant earlier intervention 1

Emergency indications:

• In ruptured AAA with suitable anatomy, EVAR is recommended over open repair to reduce peri-operative morbidity and mortality 1

EVAR vs. Open Repair Decision Algorithm

EVAR is preferred when:

• Suitable anatomy is present (60-70% of infrarenal AAA cases qualify) 1
• Life expectancy exceeds 2 years 1
• Patient has high surgical risk due to cardiopulmonary or other comorbidities 1, 3
• Peri-operative mortality with EVAR is <1% compared to 5-10% with open repair 1

Open repair is preferred when:

• Patient cannot comply with mandatory lifelong surveillance after EVAR 1
• Life expectancy is limited (<2 years), as elective AAA repair is not recommended in this population 1
• Patient is young and healthy with unsuitable EVAR anatomy and prolonged life expectancy 1

Critical Pre-Procedural Considerations

Anatomic assessment:

• Cardiovascular computed tomography (CCT) is the optimal pre-operative imaging modality to assess the entire aorta and determine EVAR feasibility 1
• Duplex ultrasound assessment of the femoro-popliteal segment should be performed to detect concomitant aneurysms 1, 4

Vascular access:

• Ultrasound-guided percutaneous femoral access is recommended due to lower complication rates and shorter operation time 1
• Local anesthesia is typically sufficient 1

Cardiac evaluation:

• Routine coronary angiography and systematic revascularization in patients with chronic coronary syndromes is NOT recommended prior to AAA repair 1
• This is a critical pitfall to avoid, as coronary revascularization before elective aortic surgery does not improve outcomes or reduce 30-day MI rates 1

Special Anatomic Considerations

Complex anatomy:

• For juxta-renal or para-renal AAA, fenestrated or branched stent endografts should be considered in high-volume centers 1
• These devices allow perfusion of visceral vessels and have shown excellent results 1

Iliac artery involvement:

• Isolated common iliac artery aneurysms typically warrant intervention at ≥3.0-3.5 cm 2

Mandatory Post-EVAR Surveillance

This is perhaps the most critical aspect of EVAR management, as patients are prone to late complications requiring re-intervention:

Initial surveillance:

• CCT re-evaluation at 6-12 months post-procedure 1
• Monitor for endoleaks, aneurysm sac size changes, and graft position 1

Long-term surveillance:

• Annual surveillance with CCT or duplex ultrasound/contrast-enhanced ultrasound for the first 5 years 1
• After 5 years of stability, imaging every 5 years is acceptable 4
• Lifelong surveillance is mandatory due to risk of endoleaks, migration, or rupture 1, 4

Common pitfall: The risk of late aortic rupture after EVAR remains >5% through 8 years, emphasizing that discontinuing surveillance prematurely is dangerous 4

Endoleak Management

Endoleaks occur in up to one-third of patients and are the most common complication 1:

• Type I (attachment site) and Type III (graft defect) endoleaks require immediate correction with re-intervention 1
• Type II endoleaks (backfilling through branch vessels) occur in ~25% of patients but may seal spontaneously 1
• If aneurysm sac grows ≥10 mm, consider embolization for Type II endoleaks 1
• Chronic anticoagulation is a risk factor for re-intervention, late conversion surgery, or mortality 1

Risk Factor Management in Vascular Disease Patients

These patients commonly have multiple cardiovascular risk factors 5:

• 89% have hypertension, 81% have hypercholesterolemia, 74% have coronary artery disease, and 39% have peripheral arterial disease 5

Essential interventions:

• Smoking cessation is mandatory to reduce aneurysm expansion risk 4, 6
• Hypertension control reduces accelerated aneurysm growth 4, 6
• Beta-adrenergic blocking agents may reduce the rate of aneurysm expansion 4
• Statin therapy for hypercholesterolemia 5

Key Caveats and Pitfalls

Patient selection errors:

• Do not perform elective AAA repair in patients with life expectancy <2 years 1
• Do not select EVAR for patients who cannot comply with lifelong surveillance requirements 1

Technical considerations:

• EVAR has higher long-term re-intervention rates compared to open repair, though peri-operative mortality is significantly lower 1, 3
• Infection of EVAR devices, while rare (0.2-5%), is complex and may require device explantation with mortality rates of 36-100% if device is retained 1

Surveillance failures:

• Relying solely on ultrasound may miss stent migration, fracture, or non-contiguous aneurysms 4
• Patient non-compliance with surveillance has been associated with 10% rupture rate compared to 0% in compliant patients 4