Vascular and Interventional RadiologyE2322. Visceral Artery Aneurysms: Current Endovascular Management for the Diagnostic Radiologist
Dubin B1, Lalezarian M2, Mohammad S2, Bahrami S1, Patel M.1 1. University of California Los Angeles Medical Center, Los Angeles, CA; 2. Olive View Medical Center, Sylmar, CA
Address correspondence to B. Dubin (email@example.com)
Background Information: Visceral artery aneurysms (VAAs) and visceral artery pseudoaneurysms (VAPAs) are rare clinical entities with an estimated incidence of 0.1–2.0%. VAAs are increasingly detected with advanced cross-sectional imaging and pose a wide spectrum of clinical outcomes ranging from asymptomatic to catastrophic rupture and death. Management of VAAs is largely based on case reports with varying opinions on the specific timing and type of treatment. For elective treatment, percutaneous repair demonstrates high rates of technical success with lower mortality, improved quality of life, and decreased length of hospitalization compared to open surgery.
Educational Goals/Teaching Points: The goal of this presentation is to review anatomy of the visceral arteries and collateral pathways; VAA and VAPA clinical presentation, demographics, natural history, and prognosis,; imaging appearance and complications; indications for observation, endovascular treatment, and surgical management; and endovascular strategies, challenges, and complications for specific aneurysm types.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques: Visceral arteries encompass the celiac, superior, and inferior mesenteric arteries as well as their branches. VAAs result from thinning of the vessel wall layers and subsequent luminal dilation whereas VAPAs result from a tear in the vessel wall with subsequent periarterial hematoma formation. While VAA is associated with a variety of conditions including atherosclerosis, medial degeneration, pregnancy, and portal hypertension, VAPA is mainly associated with trauma and iatrogenic injury. VAPAs are generally treated regardless of symptoms or size. Indications for repair of VAA are variable, but typically include the following situations: symptomatic, diameter > 2 cm, expansion > 0.5 cm per year, splenic artery aneurysm in a female of childbearing age or a patient undergoing orthotopic liver transplantation. The goal of treatment ideally is to exclude the aneurysm sac from the systemic circulation while preserving distal blood flow. Endovascular interventions using catheter-based technologies are emerging as the first-line treatment of most VAAs and VAPAs and incorporate techniques including embolization to achieve vessel occlusion and endovascular stenting or stent-grafting to preserve distal flow.
Conclusion: Given the high morbidity and mortality associated with VAA and VAPA rupture, it remains essential for the diagnostic radiologist to accurately identify these entities and apply a basic framework for stratifying patients according to their risk of rupture and need for either endovascular or surgical management.