Management of Inflammatory Aortic Aneurysms - A Scoping Review

Objective: Inflammatory abdominal aortic aneurysms (InflAAAs) account for 5 - 10% of aortic aneurysms and are characterised by retroperitoneal fibrosis. Diagnosis is often delayed, and doubts remain about the optimal management strategy. This scoping review describes the current state of knowledge on InflAAAs.

Methods: Medline, PubMed, EMBASE, and Scopus were searched for relevant studies that evaluated the diagnosis and treatment of InflAAAs. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol was followed.

Results: Fifty-seven papers were selected (low level of evidence), which included 1 554 patients, who were mostly male and heavy smokers. A triad of chronic abdominal or back pain, weight loss, and elevated inflammatory markers was highly suggestive of the diagnosis but rarely present, and fever was noted only randomly. A mantle sign was seen on computed tomography angiography (CTA) in 73 - 100% of patients. Open surgical repair (OSR) and endovascular aortic aneurysm repair (EVAR) was reported in 1 376 and 178 patients, respectively. OSR was associated with significant iatrogenic bowel (n = 22), urinary tract system (n = 7), venous (n = 30), pancreatic (n = 6), and splenic (n = 5) injuries, while EVAR was associated with lower 30 day mortality (0 - 5% vs. 0 - 32%). One and two year mortality rates were similar between the two treatment modalities (0 - 20% and 0 - 36%, respectively). EVAR was more often associated with post-operative progression of inflammation (17% vs. 0.4%), and a higher frequency of persistent hydronephrosis (> 50%) and limb occlusion (20%). Used in < 10% of patients, corticosteroids led to complete pain relief and a reduction in peri-aortic inflammation within 6 - 18 months.

Conclusion: InflAAAs are characterised by non-specific symptoms, with the mantle sign on CTA being pathognomonic. Corticosteroids may be considered a basic treatment that all patients should receive initially. Low quality data indicate that EVAR (vs. OSR) is associated with fewer intra-operative complications and lower peri-operative mortality but more late fibrosis related adverse events. International multicentre registries are required to gather more insights into this challenging pathology.