Complications After Endoluminal Stent Grafting of a Thoracic Mycotic Aneurysm
A 64-year-old man collapsed and was admitted to our hospital. He had a 3-month history of diarrhea with occasional rectal bleeding, and prior stool cultures had grown Salmonella. His ECG demonstrated a sinus tachycardia (Figure 1). A gastroscopy showed extrinsic compression of the esophagus, and computed tomography with contrast revealed a saccular aneurysm of the descending thoracic aorta with circumferential thrombus (Figure 2). No significant mediastinal adenopathy was noted, and no pulmonary masses were identified. A mycotic aneurysm was suspected, and an endoluminal stent graft inserted.
He recovered well, but had a hematemesis on postoperative day 38. A chest radiograph after the insertion of a central line demonstrated the stent graft in situ (Figure 3). Gastroscopy showed active bleeding within the esophagus and an on-table angiogram demonstrated a type 1 endoleak. A second endoluminal stent graft was inserted more proximally. A repeat gastroscopy, performed 1 week later, showed a 3-cm deficit in the mid-esophagus with a visible stent graft (Figure 4).
On day 46, the patient became paraplegic. Computed tomography showed that the T7/T8 vertebral body had been destroyed by osteomyelitis (Figure 5). No surgical intervention was undertaken, and the patient died after a catastrophic bleed.
The present case highlights the potential complications that may arise from endoluminal stent grafting of a mycotic aneurysm. A rare condition, it is estimated to account for 0.85% of all aortic aneurysms. Open repair with excision of the aneurysm and debridement of the surrounding infected inflammatory tissue followed by either in situ repair or extra-anatomic bypass is associated with significant increases in rates of morbidity and mortality.1 Furthermore, the general condition of the patient frequently precludes any attempt at open repair.2 Stent grafting has been advocated for the treatment of this condition, with a number of reports confirming the feasibility of an endoluminal approach. Midterm results compare well against those seen with open repair.2–4 As these images show, however, endoluminal stenting will not provide curative treatment if the local tissues are heavily infected. Endovascular treatment with concurrent antibiotics may be only palliative.