Visceral, Renal, and Splanchnic Artery Aneurysms

28.1Guidelines frame repair only after territory is named

Initial clinical assessment must identify the involved artery, the aneurysm type, and the organ or branch perfusion at risk. Visceral, renal, and splanchnic artery aneurysms are uncommon, and uniform size thresholds or generic treatment rules cannot be applied across all territories. The contemporary framework comes from the Society for Vascular Surgery 2020 guideline on visceral aneurysm management, the CIRSE 2024 standards for endovascular treatment of visceral and renal artery aneurysms and pseudoaneurysms, and the ACR 2026 appropriateness criteria for known or suspected renal and splanchnic artery aneurysm imaging ACR Appropriateness Criteria 2026 · CIRSE Standards Practice 2024 · SVS 2020. Those documents are most useful after the lesion has been named precisely, because the indication for repair, acceptable observation strategy, imaging pathway, and technical endpoint vary by vessel and pathology.

Classification should be explicit in the first line of the assessment. A renal artery aneurysm is primarily a renal-preservation and branch-reconstruction problem; a splenic artery aneurysm is often a special-population and collateral-perfusion problem; an SMA aneurysm is a bowel-perfusion problem; and hepatic, celiac, gastroduodenal, and pancreaticoduodenal aneurysms each carry different collateral pathways and consequences of parent-vessel occlusion CIRSE Standards Practice 2024 · SVS 2020 · Visceral Artery Aneurysms 2018. The pathology layer is equally important. A true aneurysm may be observed or repaired according to territory, symptoms, growth, patient context, and anatomic feasibility; a pseudoaneurysm, particularly after pancreatitis, trauma, or instrumentation, is generally treated with greater urgency because the sac is not composed of intact arterial wall; and an infective native aneurysm requires antimicrobial therapy and rapid exclusion planning rather than routine elective surveillance logic Infective native visceral 2025 · Visceral artery aneurysm 2001.

Assessment must therefore confirm the artery of origin, separate true aneurysm from pseudoaneurysm or infective disease, identify symptoms or rupture, identify pregnancy or transplant context, and define which branches must remain patent. Only then should the team apply society recommendations or choose between embolization, covered stent, open reconstruction, ex situ repair, or surveillance. Older rupture series and splenic artery aneurysm series remain clinically useful because they reinforce why territory and patient context matter, but they should not be used to create unsupported universal thresholds across all visceral aneurysms Visceral artery aneurysm 2001 · Splenic artery aneurysm 1990.

28.2Imaging is chosen by the question: diagnosis, planning, or follow-up

Imaging should be selected according to the clinical question: diagnosis, operative planning, endovascular navigation, or post-treatment surveillance. Contrast-enhanced CT angiography usually answers the first and broadest anatomic question because it shows the artery of origin, sac morphology, thrombus, calcification, rupture or contained leak, adjacent abdominal pathology, access vessels, and the branch relationships that determine whether exclusion alone is safe ACR Appropriateness Criteria 2026 · Visceral Artery Aneurysms 2018. In a renal artery aneurysm, the essential CTA question is whether segmental branches can be preserved. In a splenic artery aneurysm, it is whether the aneurysm is proximal, mid-arterial, distal, or hilar and whether collateral splenic perfusion is likely to remain adequate after embolization. In an SMA, hepatic, celiac, gastroduodenal, or pancreaticoduodenal aneurysm, CTA must define not only the sac but also the consequence of parent-vessel sacrifice.

CTA is also the usual planning study for both open and endovascular repair because it allows the team to measure landing zones, assess tortuosity, identify branch incorporation, choose embolization versus covered-stent strategy, and anticipate whether femoral, brachial, radial, or hybrid access will be needed ACR Appropriateness Criteria 2026 · Visceral Artery Aneurysms 2018. Catheter angiography should usually be reserved for cases in which treatment is likely to occur during the same session, or when dynamic collateral assessment will change the endpoint of embolization or stent-graft placement. It provides dynamic assessment of live inflow, outflow, collateralisation, and residual sac filling during the procedure.

The modality changes when the patient or device changes the question. MR angiography is useful when iodinated contrast is undesirable, renal function is a major concern, or long-term follow-up in a younger patient makes cumulative radiation an important consideration. It is also useful after coil embolization because metallic artefact may make CTA less reliable for small residual filling in selected patients Imaging modalities used 2025 · Follow-up true visceral 2014. Doppler ultrasound can be useful for follow-up of selected splenic or renal aneurysms and after splenic artery embolization, especially when a good acoustic window is available, but it is operator- and body-habitus dependent and should not be treated as equivalent to CTA or MRA in every territory Can Color Doppler 2023.

Surveillance after treatment is a different problem from initial diagnosis. Coils, plugs, liquid embolic material, and stent-grafts all create different imaging artefacts and failure modes. After embolization, the question is residual sac perfusion, reperfusion through collaterals, sac enlargement, splenic or hepatic infarction, and need for reintervention; after covered-stent repair, the question is endoleak-equivalent filling, stent patency, branch compromise, and migration; after open reconstruction, the question is graft or anastomotic patency and organ perfusion. Follow-up intervals should therefore be written as a territory- and treatment-specific plan at the time of repair rather than improvised later CIRSE Standards Practice 2024 · Imaging modalities used 2025 · Can Color Doppler 2023 · Follow-up true visceral 2014.

28.3Renal and splenic aneurysms carry different repair problems

Renal artery aneurysm repair is successful only if it excludes the aneurysm while preserving useful renal parenchyma. The decisive anatomic variable is usually the relationship between the sac and the renal bifurcation or segmental branches. A discrete main renal artery aneurysm with adequate proximal and distal landing zones may be suitable for covered-stent exclusion or selected coil-assisted endovascular techniques, while a branch-point or hilar aneurysm often requires a reconstruction strategy that protects two or more segmental arteries Endovascular interventions management 2021 · Hilar renal artery aneurysm repair 2020 · Reconstruction renal artery 2003. The team must determine whether the case requires simple exclusion, branch preservation, or complex renal salvage before committing to a device or incision.

Open in situ repair remains important when branch reconstruction is needed, especially for hilar disease in which losing a segmental branch would sacrifice a substantial part of the kidney. Ex situ repair with bench reconstruction and autotransplantation is reserved for complex anatomy in centers with vascular, urologic, transplant, and renal expertise, and it should be considered when in situ exposure or clamp time would make durable branch repair unsafe Kidney Autotransplantation Renal 2021 · Treatment Renal Artery 2024 · Autotransplantation Situ Surgical 2024. Robotic and laparoscopic approaches may offer selected patients a minimally invasive route to reconstruction, but they are expertise-dependent and should be judged by renal preservation, branch patency, warm ischemia control, and complication profile rather than by access route alone Robotic Surgery Visceral 2024 · Rise machines are 2024 · Robotic Renal Artery 2020. Systematic comparisons of endovascular, open, and autotransplantation strategies are useful for framing options, but heterogeneous anatomy means the best operation is often the one that preserves the kidney most reliably in that patient Outcomes endovascular open 2023. Baseline renal function, differential renal contribution when available, blood pressure behavior, and post-procedural renal function should be recorded deliberately, because aneurysm exclusion at the cost of avoidable renal loss is a poor endpoint.

Splenic artery aneurysm has a different set of hazards. Pregnancy or childbearing potential must be identified early because splenic artery aneurysm rupture during pregnancy is associated with catastrophic maternal and fetal consequences, and this context changes the tolerance for observation and the urgency of definitive treatment Splenic artery aneurysm 2023 · Splenic artery aneurysm 2013 · Splenic artery aneurysm 2009 · Review spontaneous rupture 2003. Cirrhosis and liver-transplant candidacy also matter because portal hypertension, operative timing, and transplant-related hemodynamic change can alter rupture and treatment risk Splenic Artery Aneurysm 2022. A splenic aneurysm assessment should therefore state whether the patient is pregnant, may become pregnant, has cirrhosis, is listed for transplant, or has anatomy that threatens splenic preservation.

For the typical proximal or mid-splenic artery aneurysm, endovascular embolization with coils, plugs, or other embolic agents is often the preferred strategy when collateral perfusion through the short gastric and gastroepiploic vessels is expected to maintain splenic viability Endovascular Surgical Management 2019 · Splenic artery aneurysm 2010. Covered-stent repair may be attractive when the artery is suitable and parent-vessel preservation is desirable, including selected unusual splenic artery origins or reconstructions Endovascular Repair Splenic 2023. Distal or hilar aneurysms are more likely to force a trade-off between complete exclusion and splenic preservation; laparoscopic, robotic, or open repair with ligation, aneurysmectomy, or splenectomy remains appropriate when endovascular treatment cannot provide a durable or safe endpoint Laparoscopic Robotic Surgery 2020 · Laparoscopic surgery splenic 2009. The operative plan should anticipate post-embolization pain, splenic infarction, abscess, persistent sac filling, and the need for surveillance rather than treating embolization as a one-step cure.

28.4Other splanchnic and infective aneurysms need territory-specific caution

For SMA, hepatic, celiac, gastroduodenal, and pancreaticoduodenal aneurysms, the treatment endpoint changes with the specific artery involved. In an SMA aneurysm, the dominant concern is bowel perfusion; an embolization strategy that sacrifices the trunk or important jejunal branches is fundamentally different from covered-stent exclusion that preserves the main channel or open repair with branch reconstruction Successful Repair Superior 2020. In a hepatic artery aneurysm, the team must distinguish intrahepatic from extrahepatic disease and decide whether hepatic arterial inflow can be preserved or safely replaced by collateral flow. In a celiac trunk aneurysm, total exclusion without a clear collateral plan may jeopardise hepatic, gastric, splenic, or pancreatic perfusion, so branch-preserving stent-graft repair or open reconstruction may be preferred in suitable patients CIRSE Standards Practice 2024 · Management outcome true 2021.

Gastroduodenal and pancreaticoduodenal aneurysms are often clinically linked to celiac stenosis or median arcuate ligament compression, and the procedural question is not only how to occlude the aneurysm but whether persistent high-flow collateralisation will continue to drive the lesion or create recurrence. Embolization is commonly used when inflow and outflow can be controlled, but the operator must understand the arcade anatomy and the consequences of interrupting collateral pathways to the liver, pancreas, stomach, and bowel CIRSE Standards Practice 2024 · Is open repair 2011. For all of these smaller territories, treatment selection relies on focused reports and endovascular standards rather than randomized comparisons Management outcome true 2021.

Infective native visceral artery aneurysm is a separate disease process rather than an aggressive version of a routine true aneurysm. Infection progressively weakens the arterial wall, so the rupture risk is not reliably predicted by size, the time horizon is short, and repair planning must combine source control, antimicrobial therapy, and anatomic exclusion Infective native visceral 2025. Open debridement with reconstruction remains important when the patient can tolerate it and when infected tissue or uncontrolled sepsis makes durable endovascular exclusion doubtful. Endovascular treatment may be appropriate as a bridge in an unstable patient or as a definitive strategy in selected anatomy and physiology, but the team should make that decision with microbiology, antimicrobial duration, persistent infection risk, and follow-up imaging in view CIRSE Standards Practice 2024. The safe clinical stance is to handle infective visceral aneurysm as an urgent multidisciplinary problem, not as an incidental aneurysm awaiting routine interval imaging.