Potential role of omental wrapping to prevent infection after treatment for infectious thoracic aortic aneurysms

OBJECTIVES: Postoperative infection control is one of the most important issues for infected aortic aneurysms, and the methods of preventing recurrent infection remain controversial. We previously reported that omental flaps could prevent or reduce the occurrence of infection after implanting an artificial aortic graft. However, the long-term outcomes of this strategy are unknown. We used imaging modalities to evaluate whether wrapping prosthetic grafts with omentum prevents postoperative graft infection over the long-term. METHODS: We surgically treated 521 patients with thoracic aortic aneurysm (TAA) at our hospital between July 1995 and May 2012. Of these, 22 (3.9%) (male, n= 17; mean age, 68.2 ± 11.4 years) had infectious TAA. All infectious aneurysms were resected, all patients received in-situ grafts and 16 grafts were wrapped with omentum. We followed up all survivors annually using computed tomography. We also used angiography to investigate blood circulation in omental flaps over the long-term. RESULTS: Five patients died in-hospital (operative mortality, 26.3%). The operative mortality rates of patients with and without omental wrapping were 12.5 and 50.0%, respectively (P= 0.06, NS), and the 5-year event-free survival rates were 84.6 and 33.3% (P= 0.025), respectively. Omental flaps around prosthetic grafts and their blood circulation were well-preserved over the long-term. CONCLUSIONS: Wrapping implanted artificial aortic grafts with omental flaps could prevent or reduce the occurrence of subsequent infection. Furthermore, blood circulation in the flaps must be well-preserved to improve the long-term outcomes.