What is the appropriate management for monitoring a thoracic aortic aneurysm (TAA)?

From the Guidelines

Monitoring thoracic aortic aneurysms requires regular imaging surveillance with frequency determined by aneurysm size and growth rate, as recommended by the 2024 ESC guidelines 1. The frequency of surveillance imaging should be individualized and informed by the aneurysm cause, aortic diameter, historical rate of aortic growth, how close the diameter is to the surgical threshold, and the patient’s age. Key considerations for monitoring include:

• For aneurysms smaller than 4.0 cm, imaging should be performed annually.
• For those between 4.0-4.9 cm, imaging every 6-12 months is recommended.
• Aneurysms 5.0-5.5 cm should be monitored every 3-6 months.
• Surgical intervention is typically recommended when the aneurysm reaches 5.5-6.0 cm in diameter, or earlier with rapid growth (>0.5 cm/year), symptoms, or in patients with genetic conditions like Marfan syndrome. The best imaging modality depends on aneurysm location, with options including:
• TTE, CCT, or CMR for the aortic root and ascending aorta
• CMR and CCT for the distal ascending aorta, the aortic arch, or the DTA CT angiography is the preferred imaging modality due to its excellent visualization of the entire aorta, though MRI is an alternative for patients requiring frequent monitoring to reduce radiation exposure 1. Additional management considerations include:
• Blood pressure control with a target below 130/80 mmHg using beta-blockers as first-line agents
• Avoidance of heavy lifting, extreme physical exertion, and activities that cause Valsalva maneuvers
• Smoking cessation and lipid management as important components of comprehensive management during the monitoring period.

From the Research

Monitoring Thoracic Aortic Aneurysm

• Surveillance imaging is crucial for monitoring thoracic aortic aneurysms, with the goal of preventing rupture and death 2, 3, 4
• The size of the aneurysm is a key factor in determining the risk of rupture, with larger aneurysms posing a greater risk 2, 3
• Imaging techniques such as computed tomography angiography (CTA), magnetic resonance imaging (MRI), and echocardiography can be used to monitor aneurysm size and growth rate 3, 5
• The optimal interval for imaging surveillance may vary depending on the size of the aneurysm and individual patient factors, with some studies suggesting that less frequent imaging may be sufficient for smaller aneurysms 5

Risk Factors and Management

• Hypertension and smoking are risk factors for aneurysm growth, and managing these conditions can help slow aneurysm progression 2
• Medical management, including the use of β-adrenergic blocking agents (β-blockers), may be used to slow aneurysm growth and prevent rupture 6
• Surgical or endovascular repair may be indicated for aneurysms that are large or rapidly growing, or for patients with symptoms or other high-risk features 3, 4

Imaging Surveillance Protocols

• Current guidelines recommend regular imaging surveillance, such as annual or bi-annual CTA or MRI, to monitor aneurysm size and growth rate 5
• However, some studies suggest that less frequent imaging may be sufficient for smaller aneurysms, and that patient-specific intervals for imaging follow-up may be more effective 5
• The optimal imaging protocol may depend on individual patient factors, such as aneurysm size, growth rate, and associated conditions 5