What is the preoperative evaluation for a patient with an asymptomatic Abdominal Aortic Aneurysm (AAA)?

From the Guidelines

The preoperative evaluation for a patient with an asymptomatic Abdominal Aortic Aneurysm (AAA) should include imaging studies to confirm the diagnosis, characterize the aneurysm, and inform management planning.

Key Components of Preoperative Evaluation

• Imaging modalities: CT angiography (CTA) or multidetector CT (MDCT) are the optimal choices for pre-intervention imaging, while MR angiography (MRA) may be substituted if CT cannot be performed 1.
• Aneurysm characteristics: Imaging should assess the size, morphology, and extent of the aneurysm, as well as the involvement of abdominal branches and any associated significant stenosis or aneurysm 1.
• Preoperative planning: For patients undergoing endovascular aortic aneurysm repair (EVAR), preoperative imaging should evaluate the morphology of the proximal neck, including its diameter, length, angulation, morphology, and presence of calcification 1.
• Assessment of variant anatomy: Preoperative imaging should also assess for potential variant anatomy, such as mural thrombus and atherosclerotic calcification, which can affect the choice of treatment 1.
• Screening for other diseases: Imaging studies can also identify other diseases that may affect pre-operative management, such as coronary artery disease and thoracic aortic aneurysm 1.

Recommendations for Imaging

• For AAAs ≥5.5 cm in diameter, elective repair is considered, and preoperative imaging should be performed to inform the choice of treatment 1.
• For smaller AAAs, periodic surveillance is recommended at intervals based on the maximum size of the aneurysm, with imaging modalities such as ultrasound (US) or CT 1.
• CT angiography is the primary imaging modality for both preoperative planning and follow-up after repair 1.

From the Research

Preoperative Evaluation for Asymptomatic Abdominal Aortic Aneurysm (AAA)

The preoperative evaluation for a patient with an asymptomatic Abdominal Aortic Aneurysm (AAA) involves several key considerations, including:

• Medical optimization, such as institution of beta blockade 2
• Evaluation of the aneurysm size and growth rate, with repair typically indicated for aneurysms greater than 5.5 cm in diameter or with a growth rate of more than 0.5 cm per year 3, 2
• Assessment of the patient's overall health and risk factors, such as age, tobacco use, and family history of AAA 4, 3
• Imaging studies, such as ultrasound, computed tomographic angiography, or magnetic resonance angiography, to evaluate the aneurysm and surrounding anatomy 3

Risk Factors and Indications for Intervention

The following are risk factors and indications for intervention in patients with asymptomatic AAA:

• Age > 60 years 3
• Tobacco use 3
• Male gender 3
• Family history of AAA 3, 2
• Aneurysm size > 5.5 cm in diameter 3, 2
• Rapid aneurysm growth (> 0.5 cm per year) 3, 2
• Presence of symptoms, such as abdominal or back pain 3, 5

Management Strategies

The management of asymptomatic AAA typically involves:

• Surveillance with regular imaging studies to monitor aneurysm size and growth rate 3, 6
• Medical optimization, such as blood pressure control and smoking cessation 3, 2
• Surgical repair, either open or endovascular, for aneurysms that meet indications for intervention 3, 2, 6