A first-to-podium presentation at the 2023 Charing Cross (CX) International Symposium (25–27 April, London, UK) saw Hence Verhagen (Erasmus Medical Center, Rotterdam, The Netherlands) present unique 10-year data from the ENGAGE OUS registry on the Endurant abdominal aortic aneurysm (AAA) stent graft (Medtronic). “Ever since we started doing endovascular aneurysm repair (EVAR) about 30 years ago, there have been concerns about durability,” Verhagen stated at the opening of the talk. “What we have revealed is that the survival between open and endovascular patients is the same in the long term.”
Verhagen directed his audience’s attention to previous randomised controlled trials such as EVAR1 and DREAM, which “raise[d] concern” around durability. The latter in particular showed patients in its EVAR group had “many more secondary interventions after about four years”. He also said that, though there were some other studies with long-term data (≥10 years), many of these have “strict limitations”, leading to a “paucity of long-term data” with a large stenting sample size. The reason, he said, was the high mortality in such trials— meaning that, after 10 years, “there are not that many patients left […] You need a very large group to start off with to have survival and results after 10 years.”
Setting out some details of the registry, Verhagen detailed it included 1,260 patients from 79 sites in 30 countries. The patients initially enrolled only consented to five-year follow-up, however, which required a reconsent process for 10-year follow-up—with only 49 of the initial 79 centres agreeing. This, combined with patient refusals, reduced the total cohort for long-term results to around 390 patients. “Not surprisingly, these patients were a little younger than the original and had generally fewer comorbidities,” Verhagen added.
All-cause mortality up to 10 years was analysed, revealing a survival rate of about 42%. There was no steep decline after five years, something which also held for aneurysm-related mortality (around 5% of patients). Reinterventions, “the Achilles’ heel of EVAR,” were also not found to accelerate after five years’ follow-up, with around 70% of patients free from secondary interventions. Stratified into groups undergoing reintervention at 0–5 years and at 6–10 years, Verhagen and colleagues found “very, very few” type 3 endoleaks “in the first seven years or so”, he stated, “with a slight increase at 10 years”.
Patients with a type 1a endoleak, Verhagen noted, increased in number by 4.1% at 10 years. Of those, however, 40% “started off with well-known risk factors”. Clinical events were also examined, with aneurysm rupture—“the ultimate failure”—occurring “very, very little”, increasing at a rate of 1.5% at 10 years.
Setting out a few limitations, Verhagen reminded his audience of the loss of patients during the reconsenting process, leaving a healthier cohort, as well as the fact that it was a single-arm observational registry. The take-home message, Verhagen stated, was that these were “probably unique data” up to 10 years, and that they “confirm the long-term efficacy and the durability of the Endurant stent graft with these numbers of aneurysms and mortality”. There was “no big decline” in patient outcomes at this longer follow-up point, with consistent 60% sac regression. Reviewing the most frequent causes of late adverse events, he put forward that initial hostile anatomy was a particularly influential factor. Finally, he said that “lifelong surveillance is critical for EVAR patients”.