RR13. Outside the IFU: Do Results Justify Aggressive EVAR Deployment in Short Angled Aortic Necks?

Abstract

Widespread community adoption of EVAR has led to changing referral patterns to academic centers, now consisting of more patients with unsuitable anatomy defined in the instructions for use (IFU) of endografts. Treatment of AAAs with high-risk anatomy (neck length<15mm, neck angle >60°) using commercially available devices has become more common with increasing institutional experience. We examined whether placement of approved devices in short angled necks provides acceptable durability at early and intermediate time points. 218 patients (197 men, 21 women) underwent elective EVAR at a single academic center from 2004-2007 with at least 1 year follow-up. All available pre- and post-op imaging and clinical follow-up were reviewed. Patients were divided into suitable anatomy (IFU) and high-risk (non-IFU) categories. IFU (n=143) patients underwent repair with Excluder (40%), AneuRx (34%), and Zenith (26%) devices, while non-IFU (n=75) were treated primarily with Zenith (57%). Demographics between the groups were similar, and anatomic details are in Table 1. Operative mortality was 1.4% and morbidity was 11.9%, with mean follow-up of 24 months (range 1-60). Non-IFU patients tended to have larger sac diameters, shorter, conical, and more angled necks, and were more likely to require suprarenal fixation, placement of proximal cuffs, and increased fluoroscopy time. There were no early or late surgical conversions. Rates of migration, endoleak, need for 2nd procedures, sac regression, and freedom from aneurysm-related death were similar between the groups.Tabled 1Preoperative AAA measurementsTotal (n=218)IFU (n=143)Non-IFU (n=75)P-valueAAA max diameter (mm)58.556.961.5.002Neck length (mm)242513<.0001% Neck length < 10mm10.6%0%30.7%<.0001% Conical necks33.5%25.2%49.3%<.0001Neck angulation (deg)301559<.0001% Neck angle >60 deg23.8%0.7%68%<.0001Associated iliac aneurysm24.8%25.9%22.7%NSProcedural characteristics% Suprarenal fixation use37.2%26.6%57.3%<.0001% Proximal cuff use6.0%2.1%13.3%.003Estimated blood loss (mL)357347377NSFluoroscopy time (min)27.124.731.3.02Contrast use (mL)118118119NSMid-term Outcomes% Migration>10mm2.3%2.1%2.7%NS% Type I endoleak5.5%5.6%5.3%NS% Type II endoleak37.6%41.3%30.7%NS% 2nd procedure16.5%17.5%14.7%NSMean sac regression (mm)−5.1−4.9−5.5NSKaplan-Meier EstimatesFreedom from aneurysm-related death2-year 3-year97.1% 97.1%98.5% 98.5%NS NSOverall survival2-year84.8%88.2%NS3-year81.6 %77.9%NS Open table in a new tab EVAR can be performed safely in high-risk patients with unfavorable neck anatomy using commercially-available endografts. Suprarenal fixation and proximal cuffs are often required for optimal results. Mid-term outcomes are comparable to those achieved in patients with suitable anatomy using the same devices. Long-term follow-up will continue to be necessary to confirm the benefit of treating these high-risk patients.