Staged Total Exclusion of the Aorta for Chronic Type B Aortic Dissection: A Case Report

Background: Hybrid techniques for repair of extensive thoracoabdominal aneurysms have been previously described. Variable lengths of the thoracic and abdominal aorta have been excluded or replaced using these techniques with good outcomes. The most feared complication of this approach is spinal cord ischemia, as intercostal arteries are not reimplanted. We describe a five-stage endograft repair of a complex, chronic Stanford type B aortic dissection.
Case Report: A 50-year-old man with a history of chronic type B aortic dissection developed aneurysmal dilatation of the proximal descending thoracic aorta with a maximum diameter of 7 cm. His dissection extended into both iliac arteries. The celiac trunk, superior mesenteric artery and left renal artery were perfused by the false lumen. The infra-renal abdominal aorta measured 5.3 cm. He was treated initially with a proximal thoracic endograft and carotid-subclavian bypass. A type IA endoleak required proximal extension with exclusion of the aortic arch and ascending aorto-innominate and left carotid bypass. An abdominal endograft was deployed simultaneously to compress the false lumen in the aneurysmal infra-renal aorta. An endoleak in the left iliac limb and progression of the dissection in the right internal iliac artery required bilateral iliac limb extensions. A surveillance CT angiogram revealed persistent perfusion of the false lumen through perivisceral fenestrations. After re-evaluating all therapeutic options, including medical management, a hybrid procedure was performed to exclude the descending and perivisceral aorta. Mesenteric and bilateral renal bypass grafts originating from the external iliac artery were performed followed by endografting of the remaining descending thoracic and abdominal aorta. Spinal cord protective measures, including spinal fluid drainage and lower extremity motor-evoked potential monitoring, were used during the case. The patient did not have any neurological sequelae and made an excellent post-operative recovery. A subsequent CT angiogram confirmed thrombosis of the false lumen with no endoleak.
Conclusion: Chronic aortic dissection with aneurysmal enlargement results in complex aortic pathology. Hemodynamic changes that occur when the aorta is excluded in segments are sometimes unpredictable due to multiple fenestrations throughout the dissected aorta. In this case, the aorta was excluded from the ascending arch to both external iliac arteries using endografts without spinal cord complication. Aortic arch branches, visceral and renal arteries were bypassed using hybrid technique. This is the first reported case in which the entire native aorta and iliac arteries to the external iliac branches were excluded with endografts. This case report illustrates the feasibility of the hybrid technique in selected patients when confronted with complex aortic pathology.