Surgical Indications for Descending Thoracic Aortic Pseudoaneurysms

Definition and Risk

• Aortic pseudoaneurysm is defined as a dilation of the aorta due to disruption of all wall layers, which is only contained by periaortic connective tissue 2
• When the pressure of the pseudoaneurysm exceeds the maximally tolerated wall tension of the surrounding tissue, fatal rupture occurs 2
• Other life-threatening complications include fistula formation and compression or erosion of surrounding structures 2

Specific Indications for Intervention

• All pseudoaneurysms require intervention regardless of size due to their inherent instability and high risk of rupture 2
• Symptomatic pseudoaneurysms require immediate intervention 1
• Signs of contained rupture necessitate urgent intervention 3, 2
• Recurrent or refractory pain in patients with pseudoaneurysms identifies those at highest risk of rupture 2

Treatment Approach Selection

Endovascular Approach (Preferred)

• Endovascular stent grafting should be strongly considered when anatomically feasible (Class I recommendation, Level of Evidence B) 1, 4
• Particularly valuable for patients with significant comorbidities (advanced age, cardiac, pulmonary, or renal dysfunction) 4
• Benefits include absence of thoracotomy incision, no need for partial or total extracorporeal circulatory support, and lower hospital morbidity rates and shorter length of hospital stay 4

Contraindications to Endovascular Approach

• Absence of suitable "landing zones" above and below the aneurysm 4
• Aortic diameter at landing zones exceeding recommendations for largest available endovascular grafts 4
• Lack of vascular access sites for large-bore sheaths 4
• Severe atherosclerosis and intraluminal thrombus (relative contraindication due to embolic stroke risk) 4

Open Surgical Approach

• Indicated when endovascular repair is not technically feasible 5
• May be necessary for patients with connective tissue disorders like Marfan syndrome 5, 6

Special Considerations

• Pseudoaneurysms following trauma or iatrogenic causes may have different anatomical considerations that affect treatment choice 2
• For infected pseudoaneurysms, additional antimicrobial therapy is essential alongside intervention 2
• Careful imaging assessment with CT angiography and/or MRI is crucial for proper planning of intervention 3, 2