Inflammatory abdominal aortic aneurysm:clinical features and long term outcome in comparison with atherosclerotic abdominal aortic aneurysm

Background Inflammatory abdominal aortic aneurysms (lAAAs) are rare but distinct clinical entities of atheroscleroticabdominal aortic aneurysms (aAAAs). In this study we report a 20-year single institution experience for lAAA and analyzetheir clinical features and long term outcome in comparison with aAAA.Methods Between 1988 and 2008, 412 cases of abdominal aortic aneurysms (AAAs) underwent elective surgicaloperations, 11 (2.7%) of whom were diagnosed as lAAAs and 389 (94.4%) were diagnosed as aAAAs. The former groupwas matched in a case control fashion to a group of 33 patients with aAAAs having similar characteristics of age, gender,and preoperative risk factors. All available clinical, pathologic, and postoperative variables were retrospectively reviewed,and the two groups were compared.Results The two groups did not differ significantly in clinical characteristics and preoperative risk factors, althoughpatients with lAAAs were significantly more symptomatic (100% vs. 42.4%, P=0.001) and had larger aneurysms onadmission ((7.4±0.7) cm vs. (6.3±0.9) cm, P=0.006). In lAAAs, the preoperative erythrocyte sedimentation rate was foundto be significantly elevated compared to aAAA group ((44.5±9.1) mm/h vs. (11.4±5.4) mm/h, P<0.05). Surgical morbidityand mortality rates did not differ between the two groups. The operation time for patients with lAAAs was significantlylonger than that for patients with aAAAs ((308±36) minutes vs. (224±46) minutes, P <0.05), but the cross-clamp time wassimilar in both groups ((41.5±6.2) minutes vs. (41.8±6.2) minutes, P=0.92). A five-year survival rate analysis showed nosignificant difference between the two groups (P=0.711).Conclusions Despite having more symptoms, larger size and longer operation time, patients with lAAA can now betreated with approaches that cause low morbidity and mortality, similar to patients with aAAA. Long term outcome of lAAApatients is of no difference from aAAA patients.