Safety and durability of infrarenal aorta as distal landing zone in fenestrated or branched endograft repair for thoracoabdominal aneurysm

Abstract

Objective: Manufacturers often recommend the iliac arteries as the distal landing zone in fenestrated or branched endovascular aortic repair (FB-EVAR) for thoracoabdominal aneurysm. It is not uncommon to choose distal landing at the infrarenal aorta for preservation of lumbar arteries or the inferior mesenteric artery (IMA); however, the safety and durability of this procedure have not been verified in the literature.

Methods: Consecutive patients who underwent FB-EVAR with distal landing at the infrarenal aorta were reviewed retrospectively. The primary outcome measured any type IB endoleak over time. Secondary outcomes measured perioperative complications of paraplegia and bowel ischemia, preservation of lumbar artery and IMA, and degeneration of infrarenal aorta (diameter of infrarenal aorta at landing zone) and common iliac arteries (maximum diameters) over time.

Results: Between August 2011 and August 2017, 40 patients (40% male with a mean age of 72 ± 8 years) affected by types I (37.5%), II (25.0%), III (20.0%), and V (17.5%) thoracoabdominal aneurysms were included. The mean aneurysm diameter was 6.4 ± 1.5 cm. There was no immediate or delayed type IB endoleak with mean follow-up period of 15 ± 18 months (range, 0-72 months). Postoperative complications included six (15%) spinal cord ischemia (five temporary and one permanent) and no mesenteric ischemia. There were three deaths (7.5%) within 30 days. Follow-up with computed tomography arteriography showed that 37 patients (92.5%) had at least one lumbar artery preserved. Out of the 31 preoperatively patent IMA, 23 (74.2%) were preserved. There was one incidental finding of new focal dissection distal to the stent graft end. Mean infrarenal aorta diameters were 24.8, 27.7, 27.7, and 29.4 mm immediately preoperatively, and at 1 and 2 years postoperatively, respectively. The mean maximal right common iliac diameters were stable and measured 15.8, 15.9, and 14.8 mm preoperatively, immediately postoperatively, and 1 year postoperatively, respectively. Mean maximal left common iliac diameters were also stable and measured 15.7, 15.9, and 14.7 mm preoperatively, immediately postoperatively, and at 1 year postoperatively, respectively.

Conclusions: Our early experience showed that distal landing at the infrarenal aorta was secure in FB-EVAR with no type IB endoleak, although the observation of gradual infrarenal aortic degeneration mandates regular surveillance.

Keywords: Aortic degeneration; Distal landing zone; Endoleak; Endovascular aortic repair; Thoracoabdominal aortic aneurysm.