Synopsis
Recognise rupture and infection, classify the involved vessel correctly, and apply current vessel-specific treatment and surveillance thresholds without using an obsolete universal diameter rule.
- Resuscitate suspected rupture and involve vascular surgery and interventional radiology immediately; elective size thresholds are irrelevant in shock.
- Symptomatic true visceral artery aneurysms require urgent repair assessment whatever their size or location, after checking that symptoms are plausibly attributable.
- For asymptomatic true aneurysms, use the named vessel: splenic, hepatic, coeliac, superior mesenteric and renal generally use 30 mm, while pancreaticoduodenal uses 15 mm. Pregnancy overrides size for splenic and renal aneurysms, and any-size splenic treatment may be considered in women of childbearing age.
Key red flags
Haemodynamic instability, falling haemoglobin, peritonism, retroperitoneal blood or active extravasation indicates rupture until proved otherwise.
New focal pain attributable to a true visceral aneurysm makes it symptomatic; ESVS recommends urgent repair irrespective of vessel or size.
Fever, bacteraemia, endocarditis or inflammatory change around an aneurysm suggests a mycotic lesion requiring urgent source control and antibiotics.
Pregnancy with a splenic or renal artery aneurysm changes the elective threshold because rupture can be catastrophic at a small diameter.
A lesion reported as a pseudoaneurysm needs separate urgent specialist reasoning; ESVS 2025 true-aneurysm thresholds must not be copied onto it.
Pain may be sudden and focal or diffuse, followed by hypotension, syncope, peritonism or gastrointestinal bleeding. A contained retroperitoneal rupture can transiently preserve blood pressure.
Persistent focal abdominal, flank or back pain without another explanation may reflect expansion, compression, embolisation or impending rupture. Symptoms override an elective diameter threshold.
Fever, malaise, positive blood cultures, endocarditis and perivascular inflammation raise concern for infection. The combination of sepsis and arterial wall disruption has high rupture risk.
Investigation priorities
Confirm the lesion, measure it orthogonally and plan haemorrhage control or elective repair.
Management branches
Shock, active bleeding or symptoms plausibly attributable to a visceral aneurysm.
- Resuscitate with major-haemorrhage principles, obtain immediate senior vascular and interventional-radiology involvement, and perform arterial-phase CTA only if it does not delay control.
- Treat a symptomatic true aneurysm urgently regardless of diameter; choose endovascular repair when anatomy and physiology permit, with open or hybrid control when necessary.