Endovascular Repair of a Ruptured Mycotic Aneurysm Involving the Descending Thoracic Aorta

Purpose: To describe a case of an endovascular repair of a ruptured infected thoracic aortic aneurysm and to provide a review of the current literature involving treatment.

Materials and Methods: A 64-year-old woman with a history of essential thrombocytosis, chronic portal and splenic vein occlusion, and deep vein thrombosis who was taking Coumadin presented with subjective fevers, nausea, and vomiting, and midback pain. She was diagnosed with pneumonia and started on antibiotics. Computed tomography (CT) obtained on hospital day (HD) 2 demonstrated a large 6.4-cm irregular saccular aneurysm versus pseudoaneurysm of the distal descending thoracic aorta. Because of hemodynamic and respiratory deterioration, a second CT of the chest on HD 5 demonstrated enlargement and further irregularity of the thoracic aneurysm and worsening pleural effusions. Significant periaortic inflammatory changes and persistent leukocytosis brought up the concern of a possible ruptured mycotic aneurysm. The patient was deemed a poor surgical candidate and underwent an emergent endovascular repair with plans for explantation and open repair after stabilization. We will further discuss the procedure in detail with a pictorial review.

Results: Infected aortic aneurysms are associated with significant morbidity and mortality. Risk factors for the development of infected aneurysms include antecedent infections, immunosuppression, atherosclerosis, and preexisting aneurysms. Although bacterial translocation is rare, it may occur because of septic emboli of the vasa vasorum, direct inoculation, or contiguous infections. The clinical presentation is usually vague, and imaging is usually required for diagnosis. Blood cultures should be obtained; however, findings may be negative in 25% to 50% of cases (as in this case). CT angiography findings suggesting an infected aneurysm include an irregular aneurysm, periaortic inflammation, consolidation, fluid collection, and intramural air. Although no randomized control trials have been conducted to guide the treatment of patients with infected aortic aneurysms, general considerations include antibiotics and surgical debridement, aneurysmal excision, and reconstruction. Endovascular repair has been gaining popularity in recent years and is reserved for high-risk patients and those with aneurysm rupture as a temporizing measure.

Conclusions: Endovascular aortic repair is indicated as a temporizing measure for ruptured infected aneurysms and in patients with infected aneurysms who are not candidates for open repair.