Infected stent graft and severe aortitis after transcaval glue embolization of type II endoleak: a case report.

Background: Type II endoleaks are common and embolization is often performed if treatment is necessary. Although transarterial embolization is common, other methods including trans-caval embolization are also utilized. Complications can occur and we report a case of infection that was challenging to diagnose and treat. There is no data regarding the risk of aortic stent graft infection after trans-caval embolization with n-butyl 2-cyanoacrylate (n-BCA) glue of a type II endoleak.

Case description: We report a rare case of infected, Gore Excluder infrarenal stent graft after transcaval embolization with coil and n-BCA glue to treat a type II endoleak in a 71-year-old male. The endoleak caused a rapid sac enlargement. The stent graft was placed 5 years earlier electively. Soon after the endoleak embolization, the patient experienced abdominal pain and malaise. There was an intense inflammatory reaction involving the aneurysm wall and the adjacent bowel mesentery. Our differential included normal inflammation after embolization vs. infection and this was difficult to distinguish. The infection was confirmed by positron emission tomography scan and tissue biopsy. The patient was deemed high-risk for surgery because of his extensive cardiac history, status post coronary bypass and tissue mitral valve replacement, congestive heart failure with residual left ventricular ejection fraction of 36%. He was optimized by correcting fluid status, administration of intravenous antibiotic, and nutrition consultation with dietary supplementation before surgery over the course of 2 weeks. The graft was explanted through a transabdominal approach, and the aorta was reconstructed with cryopreserved allograft. Interestingly, the small and large intestine with their mesentery were found to be plastered to the aneurysm sac. The post-operative course was unremarkable except for a transient acute kidney injury that resolved within 1 week. Follow-up computed tomography scan at 6 months showed widely patent bypass.

Conclusions: Glue embolization induces inflammation promoting thrombus formation inside the aneurysm sac. With a transcaval approach to the sac, there is the risk of extravasation of glue outside the sac as well as contamination of the graft with instrumentation. Differentiating between inflammation and infection can be difficult, and tissue biopsy provided the most conclusive diagnosis. Risk minimization considerations include, pre-operative optimization, a transabdominal approach, ureteral stenting, and tissue buttressing of anastomosis.