Delayed complication of iliac artery aneurysm repair—from critical limb ischemia to mixed shock: a case report

BACKGROUND: Iliac artery aneurysms (IAA) can exist in isolation or in combination abdominal aortic aneurysmal disease. Isolated IAA are rare, often asymptomatic and will present with compression of local structures or incidentally on imaging. Treatment depends on symptomology and size. While endovascular repair has become the preferred method in recent years, for patients with extensive aneurysmal disease, the standard of care is surgical procedure. Acute limb ischemia (ALI) related to aneurysmal disease can occur by progression of untreated disease or rarely, as a complication of its repair. CASE DESCRIPTION: A man in his 70s who had previously undergone aorto-bifemoral repair for severe aorto-iliac aneurysmal disease nine years prior presented to the emergency department (ED) with a cold left lower extremity concerning for ALI. Emergent aortogram revealed progression of aneurysmal disease with extrinsic graft compression by a giant left iliac aneurysm and femoral artery thrombosis. He underwent femoral artery thrombectomy, bilateral graft limb stent placement and left femoral graft anastomosis balloon angioplasty with stent placement achieving restoration of limb flow and resolution of symptoms. He was discharged and unfortunately lost in follow up. He returned eight months later with mixed shock due to a ruptured left iliac aneurysm. Despite aggressive treatment measures, patient progressed to multi-organ failure, cardiopulmonary arrest, and death. CONCLUSIONS: Our case illustrates an unusual mechanism of ALI by extrinsic graft compression from an expanding left IAA over the course of eight years through delayed retrograde collateral flow. It highlights its life-threating late complications and the importance of close follow-up after abdominal aneurysm surgical repair.