Arterial
Procedure Guide
Pseudoaneurysm (up to 25% risk of rupture)
Symptomatic true aneurysm
Asymptomatic true aneurysm >2 cm (>3 cm for splenic and renal) or expansion >0.5 cm/yr
Rupture risk 25-40%, 76% mortality with rupture
Higher risk of rupture if connective tissue dx, pregnancy, liver tx, or portal HTN
Etiologies: trauma, iatrogenic, sepsis, pancreatitis, vascular Ehlers-Danlos, Marfans, cystic medial necrosis, polyarteritis nodosa, fibromuscular dysplasia, amphetamine abuse, Behcet disease, celiac or SMA occlusion, splenomegaly
No absolute contraindications.
Allergy to embolic material or contrast
Hemodynamic instability / aneurysm rupture
Uncorrected coagulopathy
Surgery: similar technical success, mortality, and morbidity. Possible better durability but longer recovery.
Surgery is likely ideal for emergent cases whereas endovascular approaches superior electively.
Embolization 90-100% technical and clinical success for elective cases.
Systematic review: 22 studies, 665 aneurysms, 93.6% technical success, 99.1% visceral preservation, 4.4% reintervention
Stent grafts also have high technical success for vessels 5 mm or larger.
Some reports of decent outcomes for small arteries, e.g., proper hepatic artery, with smaller coronary stents off label.
Minimal risk of graft infection even if excluding a pseudoaneurysm secondary to infection (e.g. necrotizing pancreatitis). No cases of graft infection reported.
Bare metal stents also highly successful with mechanism likely similar to flow diverter in neuroIR with less aneurysm flow causing thrombosis.
Direct puncture also an option if there is no clear endovascular route.
Coils are superior to thrombin injection in terms of durability.
CTA/MRA to assess vascular anatomy and plan procedure:
Need front and back door closed?
Wide vs narrow neck?
Can parent vessel be safely occluded?
Labs: PT/INR, CBC, serum creatinine
Arterial access (CFA or radial).
Select parent vessel with angled catheter (e.g. C2) and glidewire.
Some administer 1-2 mg glucagon to decrease bowel peristalsis.
Selective angiography in multiple projections to characterize anatomy.
Cone beam CT can be helpful for more complex anatomy.
Often helpful to advance a long curved sheath to provide additional support.
Gain access to the aneurysm/feeding vessel if planning to embolize vs wire access passed the lesion if planning to stent graft.
Distal access may require and microwire/microcatheter system. Followed by exchange for a stiffer microwire to advance devices (e.g. Spartacore, Steelcore).
Treat aneurysm with embolization and/or stent graft placement.
Stent graft is often ideal for preservation of the parent vessel. Even with a small neck, the aneurysm may continue to grow with embolization alone.
Conversely, if the parent vessel can be safely sacrificed, embolization is often easier and definitive. Be sure to embolize both the “back” and “front” door of the parent vessel.
Post-treatment angiography to confirm complete exclusion of the aneurysm.
Remove catheter/sheath and obtain hemostasis.
Minor: insignificant end organ infarcts, groin hematoma, post-embolization syndrome
Major (3.7%): visceral infarction or atrophy, abscess, major access site complication, hemorrhage, cardiac/cerebrovascular event
Some admit for overnight observation others do as an outpatient pending etiology and context, e.g., incidentally found splenic artery aneurysm with routine treatment vs intermittent bleed pseudoaneurysm in the setting of necrotizing pancreatitis.
Follow up CTA/MRA in 3-6 months.