Application of Neoaortoiliac System For Contained Rupture of Mycotic Infrarenal Aortic Aneurysm

ABSTRACT

Funding: None. Synopsis 61-year-old male who initially presented to an outside facility with streptococcal pneumoniae meningitis and bacteremia. Of note, he had history of COVID-19 pneumonia a month prior. On hospital day 15, he reported sudden onset lower back pain prompting imaging which demonstrated a contained rupture of an infrarenal aortic aneurysm that had significantly evolved in comparison to admission imaging where his infrarenal aorta had the largest dimension measuring 2.9cm. We present the successful application of neoaortoiliac system (NAIS). Method(s) Proceeding with midline laparotomy we encountered dense adhesive disease due to his history of surgery for colon cancer. After adhesiolysis, we exposed the aorta and aneurysm with severe surrounding inflammatory changes. 20cm of femoral vein was harvested, reversed, and joined for a span of 4cm using an Endo GIA 45mm vascular load to create our neoaorta. Proximal and distal clamp zones were developed. Upon entering the aneurysm, a foul smell was encountered, revealing that the noxious process had destroyed the posterior wall of the aorta and paraspinal tissues. Our neoaorta was anastomosed in end-to-end fashion to the infrarenal aorta and subsequently to the common iliac arteries. Flow was initially restored to the hypogastric arteries and then the external iliac arteries. The retroperitoneum was closed over our repair and covered with omentum. Result(s) On post-operative day 2, he had hematochezia;intraoperatively, the IMA was noted to be 1mm in size, though had brisk back-bleeding and was ultimately ligated. A flexible sigmoidoscopy revealed ischemic sloughing of the sigmoid colon near his previous anastomosis from his colon cancer resection though no transmural necrosis. He remains on high-dose ceftriaxone to complete a 6-week course and metronidazole for 10 days due to his sigmoid mucosal ischemia per infectious disease recommendations. He is now post-operative day 10 and remains in the ICU. Conclusion(s) Mycotic aortic aneurysms constitute 1-1.8% of aortic aneurysms. The standard of treatment is aggressive debridement of involved aortic wall and periaortic tissue, in-situ or extra-anatomic reconstruction, coverage with an omental flap and long-term antibiotic therapy. NAIS is resistant to infection and aneurysmal dilation, however, is a time-consuming procedure with a mean completion time of 8 hours. Dorweiler et al. demonstrated that vascular reconstruction with femoral vein in infected aortoiliofemoral fields has a mortality of 9-10% with negligible rate of late complications (graft stenosis, thrombosis, and dilation) and that venous morbidity after femoral vein harvest is well tolerated. Clagett et al. demonstrated that NAIS fashioned from greater saphenous vein had a failure rate requiring intervention of 64% compared to 0% for those constructed with deep femoral vein. Lastly, it is important to note that our patient was previously COVID-19 positive. This case demonstrates that the sequela of COVID-19 may have been a significant factor in our patient's pathophysiology. As we continue to learn about the effects of COVID-19 on vascular pathology, we must keep a large repertoire of operative techniques at hand in order to treat complex presentations of vascular emergencies. [Formula presented] [Formula presented] [Formula presented] Institution Orlando Health, Orlando, FLCopyright © 2022