A Nationwide Study on Endovascular Treatment of Mycotic Thoracic Aortic Aneurysms

Abstract

Introduction - Mycotic aortic aneurysms are rare, life threatening and complex. Current knowledge on treatment is scarce and based on small single-centre case series with heterogenic case-mixes. This nationwide multicentre study aims to assess endovascular treatment for mycotic aneurysms of the thoracic aorta (MTAAs). Methods - All patients treated endovascularly for MTAAs between 2010 and 2016 were identified in the national vascular registry. All eight tertiary vascular units in the nation participated in retrieving data and retrospective chart review according to a predefined protocol. Results - 42 patients were identified, and two additional patients were treated with open repair. Median age was 71 years (Standard deviation SD 7.4), 23 (55%) were men, 32 (76%) had cardiovascular comorbidity, 12 (29%) were immunosuppressed, and 11 (26%) presented with rupture. The aneurysms were located in the aortic arch in 5 patients (12%), descending aorta in 33 (79%), and multiple locations including the thoracic aorta in 4 (9%). Positive culture was obtained in 21 (50%). The two most prevalent infectious agents were Stafylococcus aureus (n=11, 25% of all MTAA patients), and Streptococcus sp (n=3, 7%). Thoracic endovascular aortic repair (TEVAR) was performed (n=31), fenestrated/branched TEVAR (n=5), and hybrid visceral deviation and stentgrafting (n=6). Total survival was at 3-months 86% (95% CI 81-91%), 1-year 80% (74-86%), and 5-years 73% (66-80%). Mean follow-up among survivors (>90-days) was 35 months (range 4-212). Antibiotics were administered for a median of 7 weeks, range 0-220 weeks. Infection-related complications occurred in 6 patients (14%); sepsis n=2, graft infection n=1, recurrent mycotic aortic aneurysm=1, and aorto-esophageal/brochial fistula n=2. All occurred within the first year. Both cases with aortic fistulation died, the patient with graft infection was converted to an open procedure with explantation of the graft and survived, the recurrent mycotic aneurysm was treated with stentgraft and antibiotics and survived, and the two sepsis cases were treated successfully with antibiotics. Reoperation was performed in 8 patients (18%; infection-related complication n=3, endoleakage n=4, and stent graft occlusion n=1), of which one was converted to an open procedure. Seven patients (17%) had an aneurysm-related death. Conclusion - In this nationwide analysis of endovascularly treated MTAA-patients survival was acceptable. This minimally invasive treatment enabled surgical repair in elderly, comorbid patients with a challenging anatomy with acceptable rates of infection-related complications and reoperation.