The Suitability of Thoraco-abdominal Aortic Aneurysms for Branched or Fenestrated Stent Grafts – And the Development of a New Scoring Method to Aid Case Assessment

Abstract

Objective To determine the proportion of TAAAs which might be suitable for pure endovascular repair based on aneurysm morphology and to develop an MDCTA based scoring system to grade case complexity. Design 70 consecutive MDCTA of patients with TAAAs were analysed in relation to specific morphological characteristics. Methods The characteristics included potential stent landing zone lengths, arch angulation, thoraco-abdominal aorta angulation, branch vessel origin stenosis, access tortuosity/diameter and aortic dissection. Results 60% of TAAAs would be suitable for branched/fenestrated stent grafting but 40% are unsuitable due to adverse anatomy. 27% had an aortic arch angulation of ≤110° and 24% had descending thoracic aorta angulation of ≤90°. Significant ostial stenosis was identified in 31% of celiac arteries, 7% superior mesenteric arteries, 24% left renal artery and 19% right renal arteries. 11% of left common iliac and 7% right common iliac arteries had angulation of ≤70°. There were 26 cases with aortic dissection and 54% of these had a true lumen of ≤26 mm. Conclusion Successful fenestrated/branched stent graft repair of TAAAs requires adequate landing zones, cannulation of visceral arteries and suitable diameter access vessels. 60% of TAAAs studied were suitable for branched/fenestrated stent graft repair but 40% of TAAAs were unsuitable; aortic angulation, visceral vessel ostial stenosis and dissection true lumen diameter were the principle issues. Development in stent technology may address these anatomical challenges.