Synopsis:Multiple randomized trials have demonstrated an early survival benefit, albeit limited to a few years, for endovascular aneurysm repair (EVAR) compared to open repair of abdominal aortic aneurysms (AAA). It is unknown whether either intervention is better for long-term (>10 year) survival. This trial is an extension of EVAR trial 1, which originally randomized 1252 patients, fit for either intervention, to EVAR vs open repair between 1999 and 2004. The primary aim was to report the long-term results (up to 15 years) in terms of aneurysm-related and total mortality. Beyond 8 years of follow-up, open repair had a significantly lower total mortality (HR 1.25, p=0.048) and aneurysm-related mortality (HR 5.82, p<0.01). The increased aneurysm-related mortality in the EVAR group was attributable to secondary aortic sac rupture (13 deaths [7%] EVAR vs. 2 deaths [1%] in open repair), which also contributed to higher total mortality. Over the complete follow-up period, however, the mean total mortality and aneurysm-related mortality were not significantly different between groups. The rate of re-interventions was higher in the EVAR group at all timepoints. The authors concluded that despite the well-established early survival benefit of EVAR, the inferior late survival benefit and durability compared to open repair warrants lifelong surveillance to monitor sac size and timely re-intervention to correct underlying causes of expansion when necessary. Limitations of this study include the use of stent graft devices, pre-operative CT imaging and fluoroscopy (to establish size and placement of endografts), considered outdated by today’s standards. Stent grafts since then have undergone multiple iterations that address challenging proximal aortic neck anatomy, device migration, fabric fatigue, and branched designs for maintaining visceral perfusion. The corollary is that experience with open repair has simultaneously been decreasing, which may have the opposite effect on outcomes moving forward. Lastly, open repair patients had less diligent follow-up in this study, which may have led to an underestimation of aneurysm-related mortality as well as re-interventions, but may not have impacted total mortality.