Complex EVAR for abdominal aorto-iliac aneurysm (AAIA) is associated with high rate of endoleak and less aortic sac shrinkage compared to conventional EVAR for AAA.

INTRODUCTION: Endovascular repair (EVAR) for large abdominal aortic aneurysm (AAA) in anatomically suitable patients is associated with low early mortality and morbidity. However, EVAR is associated with a significant risk of late complication and a high cumulative re-intervention rate. Many large experienced centres have offered complex EVAR to challenging aortic anatomies such as abdominal aorto-iliac aneurysm (AAIA). We hypothesised that complex EVAR, for AAIA, would be associated with an increased risk of late graft-related complications.
METHODS: The design was a Retrospective Clinical Cohort Study. From a prospective computerised database we identified consecutive patients undergoing EVAR in a single institution between 2008 and 2009. We retrieved analysis clinical data and digital Computed Tomographic Angiography (CTA) scans carried out pre-, early post-, and late post-EVAR. We compared patients undergoing complex EVAR for AAIA with those undergoing conventional standard EVAR for AAA.
RESULTS: We identified 93 consecutive patients undergoing EVAR, 13 patients were excluded (3 eEVAR, 1 TEVAR, 9 data could not be retrieved) leaving 80 patients for analysis, 63 male and 17 female, average age 74.5 years (range 57-86), average follow-up 38 months (range 27-50), primary EVAR success was 100% and there was no mortality. Complex EVAR, EVAR plus internal iliac artery embolisation (+IIAE) and extension of the ipsilateral graft limb to the external iliac artery, for AAIA were carried out in 19/80 patients. After standard EVAR, late post-EVAR AAA sac diameter was significantly reduced in EVAR (63.24 ± 9.76 vs 54.26 ± 13.70, p < 0.001) but not after complex EVAR+IIAE (58.89 ± 16.39 vs 52.35 ± 12.75, p = 0.62). Endoleak these were significantly more common in the complex EVAR+IIAE, 5/19 (26.32%), as compared to the standard EVAR, 11/61 (18.03%), p < 0.01. Interestingly, inferior mesenteric artery (IMA) Patency was much commoner after complex EVAR+IIAE (15/19, 78.95%) compared EVAR (29/61, 47.54%), p < 0.01.
CONCLUSION: EVAR can be carried out with low early mortality but has a significant risk of late complication, the commonest of which is endoleak. Complex EVAR for abdominal aorto-iliac aneurysm can be carried out with comparable results to conventional EVAR. However, high rates of persistent endoleak and inferior mesenteric artery patency, and lack of aneurysm sac shrinkage, would suggest they may be at increased risk of late complications and may benefit from enhanced and extended radiological surveillance.