The management of endograft infections following endovascular thoracic and abdominal aneurysm repair

Objective The management of infected aortic endografts is a challenging endeavor. Treatment of this problem has not been well defined as it is fairly uncommon. However, the incidence is increasing. This study examines the results of treatment at a single center for this morbid process. Methods A retrospective review was performed of patients treated for infected abdominal or thoracic endograft infection following previous abdominal or thoracic endovascular aneurysm repair. Data was reviewed for patient demographics, details of initial endograft implantation, presentation and timeline of subsequent infection, management of infected grafts, and outcomes during follow-up. Results Overall, 18 patients were treated for infected endografts (thoracic: six, abdominal:12). Three patients were treated between 2000 and 2006, corresponding to a 0.6% institutional incidence of endograft infection (3/473). There were no transfers for infected endografts from outside institutions. From 2006 to 2011, 15 patients underwent treatment. Six were institutional cases of infections (6/945, 0.6% infection rate), however, there was an increase in transfers (n = 9). Median time to presentation with infection from endograft implant was 90 days, with over one-half (61%) presenting within the first 3 months. Tissue and/or blood cultures were positive in 12/16 growing Escherichia coli (n = 1), group A streptococcus (n = 3), methicillin-resistant Staphylococcus aureus (n = 3), or polymicrobial infections (n = 7). The other four patients were culture negative with computed tomography evidence of gas surrounding the endograft and clinical sepsis. Ten patients (abdominal: eight, thoracic: two) were treated with endograft explantation. The remaining eight patients were considered too high-risk for explant or refused open surgery and were therefore managed conservatively without explant (abdominal: four, thoracic: four). At a mean follow-up of 24.7 months, aneurysm-related mortality was 38.9% (n = 7) and was higher for patients presenting with aortoenteric or aortobronchial fistulas (n = 6/10, 60%) ( P = .04) and for thoracic stent infections (n = 5/6; 83%) ( P = .03). The only survivor of a thoracic infection was managed surgically. Overall survival for patients with abdominal endografts (n = 12) was similar between the eight patients managed surgically (n = 6/8; 75%) and the four selected for medical management (n = 4/4; 100%) ( P = .39). All survivors remain on long-term suppressive antibiotics. Two additional patients died of unrelated causes during follow-up. Conclusions Endograft infection is a rare but increasing complication after abdominal or thoracic endovascular aneurysm repair, which carries significant associated morbidity and mortality. Most endograft infections occurred in proximity to other types of infection, suggesting that bacterial seeding of the endograft was the source. Aortoenteric and aortobronchial fistulas are common presentations, which portend a significantly worse prognosis. Thoracic endograft infections, which have the highest rate of fistulization, have the worst outcomes. Surgical excision continues to be standard of care but conservative management with intravenous antibiotics may be of benefit in certain patients with abdominal endograft infections.