Invited Commentary

Abstract

Mycotic aneurysms of the aorta are relatively rare and compose only 1% of all thoracic and abdominal aortic aneurysms [1Brown S.L. Busuttil R.W. Baker J.D. et al.Bacteriologic and surgical determinants of survival in patients with mycotic aneurysms.J Vasc Surg. 1984; 4: 541-547Google Scholar, 2Muller B.T. Wegener O.R. Grabitz K. et al.Mycotic aneurysms of the thoracic and abdominal aorta and iliac arteries: experience with anatomic and extra-anatomic repair in 33 cases.J Vasc Surg. 2001; 33: 106-113Abstract Full Text Full Text PDF PubMed Scopus (464) Google Scholar]. They are caused by a bacterial infection of the wall of the artery, leading to aneurysm formation, emboli, and rupture. Patients usually present with fever, pain, and leukocytosis. Treatment is usually bimodal with intensive antibiotic therapy as well as surgical repair. Traditional principles of surgical therapy consist of resection of the aneurysm, wide debridement, and reconstruction with an in situ graft when suprarenal and an extraanatomic bypass when the aneurysm is infrarenal [1Brown S.L. Busuttil R.W. Baker J.D. et al.Bacteriologic and surgical determinants of survival in patients with mycotic aneurysms.J Vasc Surg. 1984; 4: 541-547Google Scholar, 2Muller B.T. Wegener O.R. Grabitz K. et al.Mycotic aneurysms of the thoracic and abdominal aorta and iliac arteries: experience with anatomic and extra-anatomic repair in 33 cases.J Vasc Surg. 2001; 33: 106-113Abstract Full Text Full Text PDF PubMed Scopus (464) Google Scholar]. Using this approach, in-hospital mortality is as high as 36%, although infrarenal aneurysms have a better outcome than do aneurysms in the suprarenal position (including the thoracic aorta). In the present article, Uchida and colleagues [3Uchida N. Katayama A. Tamura K. Miwa S. Masatsugu K. Sueda T. In situ replacement for mycotic aneurysms on the thoracic and abdominal aorta using rifampicin-bonded grafting and omental pedicle grafting.Ann Thorac Surg. 2012; 93: 438-442Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar] report on 23 patients in whom they used an in situ graft reconstruction with a rifampin-bonded graft in all patients and an additional omental wrap in half the patients. The overall results are very good. They achieved eradication of infection in 22 of 23 patients and had an impressive 95% survival at 5 years. Yes, these are small numbers and there is case selection, but this is a rare problem and extensive trials will not be forthcoming. This article has 2 interesting features that could be of use to all of us when faced with an infected aneurysm: (1) As previous case reports have suggested, a rifampin-impregnated graft may be implanted successfully in an infected field [4Lachapelle K. Graham A.M. Symes J.F. Antibacterial activity, antibiotic retention, and infection resistance of a rifampin-impregnated gelatin-sealed Dacron graft.J Vasc Surg. 1994; 19: 675-682Abstract Full Text Full Text PDF PubMed Scopus (55) Google Scholar, 5Gupta K. Bandyk D.F. Johnson B.L. In situ repair of mycotic abdominal aortic aneurysms with rifampin-bonded gelatin-impregnated Dacron grafts: a preliminary report.J Vasc Surg. 1996; 24: 472Abstract Full Text Full Text PDF PubMed Scopus (67) Google Scholar]. (2) Omental coverage may provide lasting protection from graft reinfection. Of course it is impossible to ascertain the additional role of the omentum to a rifampin-bonded graft, but we know it can be quite effective [6Kuniyoshi Y. Koja K. Miyagi M. et al.Graft for mycotic thoracic aortic aneurysm: omental wrapping to prevent Infection.Ann Asian Cardiovasc Thorac. 2005; 13: 123-128Google Scholar]. If possible we should cover the graft with omentum. Although not addressed in this article, the role of endovascular repair for mycotic aneurysms appears to be growing [7Sörelius K. Mani K. Björck M. Nyman R. Wanhainen A. Endovascular repair of mycotic aortic aneurysms.J Vasc Surg. 2009; 50: 269-274Abstract Full Text Full Text PDF PubMed Scopus (68) Google Scholar]. However placing prosthetic material into an infected space seems counterintuitive. It may not work well in the long run. In Situ Replacement for Mycotic Aneurysms on the Thoracic and Abdominal Aorta Using Rifampicin-Bonded Grafting and Omental Pedicle GraftingThe Annals of Thoracic SurgeryVol. 93Issue 2PreviewThe objective of this report is to discuss the efficacy of in situ replacement for treating mycotic aneurysm, particularly using rifampicin-bonded grafts and omental pedicle grafts, on the basis of our 7 years of experience. Full-Text PDF