From the Guidelines
Endovascular Aneurysm Repair (EVAR) is primarily indicated for patients with abdominal aortic aneurysms (AAAs) measuring 5.5 cm or larger in men and 5.0 cm or larger in women, as supported by the 2022 ACC/AHA guideline for the diagnosis and management of aortic disease 1.
Key Criteria for EVAR
- Anatomical criteria:
- Adequate proximal and distal landing zones (at least 15 mm of healthy aorta)
- Appropriate iliac access vessels (typically >7 mm diameter without excessive tortuosity)
- Suitable aneurysm neck angulation (less than 60 degrees)
- Medical eligibility:
- Reasonable surgical risk
- Life expectancy exceeding 2 years to benefit from the procedure
- Ability to comply with post-EVAR surveillance protocols, including regular CT or ultrasound imaging
Contraindications and Considerations
- Contraindications include connective tissue disorders like Marfan syndrome, active infection, and severe renal insufficiency (unless plans for renal protection are implemented) 1.
- EVAR is preferred over open repair in elderly patients and those with significant comorbidities because it offers lower perioperative mortality and faster recovery, though it requires lifelong surveillance due to potential complications like endoleaks and device migration 1.
High-Risk Features
- Rapid aortic growth (≥0.5 cm/y)
- Symptomatic aneurysms
- Underlying connective tissue disorder or HTAD
- Saccular aneurysm morphology
- Female sex
- Infected aneurysm These features have been associated with a higher tendency for rupture and may justify intervention at a smaller diameter threshold 1.
From the Research
Criteria for Endovascular Aneurysm Repair (EVAR)
The criteria for EVAR include various factors such as aneurysm size, anatomy, and patient suitability.
- Aneurysm size is a critical factor, with larger aneurysms being less likely to be anatomically suitable for EVAR 2.
- The study by 2 found that aneurysm size measured by CT scanning or US imaging correlated with anatomic suitability for EVAR.
- A CT cutoff of 57.0 mm and a US cutoff of 4.87 mm were found to best predict anatomic suitability for EVAR 2.
- Other factors such as neck length, iliac artery diameter, and presence of thrombus or calcification also play a role in determining suitability for EVAR.
- Patient factors such as age, comorbidities, and overall health status are also considered when evaluating suitability for EVAR 3, 4.
- The decision to perform EVAR should be based on individual patient characteristics and aneurysm anatomy, rather than solely on aneurysm size 5.
Anatomic Suitability
Anatomic suitability for EVAR is determined by various factors, including:
- Aneurysm size and shape
- Neck length and diameter
- Iliac artery diameter and morphology
- Presence of thrombus or calcification
- The study by 2 found that larger aneurysms are less likely to be anatomically suitable for EVAR.
- The study by 3 found that patients who were excluded from EVAR due to anatomic criteria had a higher incidence of coronary artery disease and more complex repairs.
Patient Selection
Patient selection for EVAR is critical to ensure optimal outcomes.
- Patients with suitable anatomy and minimal comorbidities are ideal candidates for EVAR 6.
- Patients with severe haemodynamic instability, adverse anatomy, or device unavailability may require open repair 4.
- The study by 4 found that EVAR was feasible for selected patients with ruptured AAA, with improved immediate outcomes compared to open repair.