MIAMI BEACH – At 2 years, the Endurant stent graft was durable for abdominal aortic aneurysm, based on findings from a registry of nearly 1,300 patients.
Freedom from aneurysm-related death was 98% in the 500 registry participants who were followed for at least 2 years, reported Dr. Dittmar Böckler, of University Hospital Heidelberg, Germany.
Procedural success was nearly 98% in 1,263 participants in the ENGAGE Global Registry of patients treated with Medtronic’s Endurant system. The findings offer encouragement about "real world" endovascular aneurysm repair (EVAR) and new-generation EVAR devices, Dr. Böckler said at the International Symposium on Endovascular Therapy 2013.
Procedural success was based on a composite of technical success (99%), freedom from intraoperative death (100%), and freedom from type I and III endoleaks (98.6%). Also, there was freedom from reinterventions at 1 year (95%) in all 1,236 patients and at 2 years (93%) in the 500 patients who have been followed that long.
The risk of any type of second procedure was 5.6% at 1 year and 1.6% at 2 years. The risk of a second procedure for an endoleak was 1.4% at 1 year and 1.8% at 2 years. The total endoleak rate was a "remarkably low" 9.7% at 1 year and 9.1% at 2 years, he said.
No stent migration occurred at either time point. Sac enlargement, which is known to increase the long-term risk of aneurysm rupture, was rare, occurring in 3.4% of patients at 1 year and 2.9% at 2 years, Dr. Böckler said.
As for EVAR treatment failure, the conversion rate was "very acceptable" at 0.6% and 0.8% at 1 and 2 years, respectively, and the rupture rate was 0.2% at 1 year and remained the same at 2 years, he noted.
Stent graft occlusion occurred in 3.5% at 1 year and in 2.7% at 2 years. Similar patency was seen in 150 patients from the Endurant U.S. Investigational Device Exemption (IDE) trial; at 2 years, 3.1% of patients in that trial had occlusions.
The ENGAGE findings compare favorably with those of other studies of EVAR, including the DREAM (Dutch Randomized Endovascular Aneurysm Management) study and the OVER (Open Vs. Endovascular Repair) trial, he said.
Of note, the need for secondary intervention was halved with the Endurant system; it was 6.4% in ENGAGE and 6.1% in Endurant U.S. IDE, compared with 13.7% in OVER and 12% in DREAM.
"The clinical effectiveness of EVAR is well established," Dr. Böckler said, citing the outcomes of numerous EVAR trials. The 2-year outcomes begin to address the remaining concerns and questions, including whether outcomes are durable, whether performance outside of controlled trials will match that seen in trials, whether newer technology will perform as well as or better than older technology, and whether it will perform as well in real-world settings and in different populations and practices.
The registry – a multicenter, postmarket, noninterventional, nonrandomized prospective study – includes 1,263 patients enrolled between March 2009 and April 2011 to assess real-world safety and clinical performance of the Endurant stent graft system. Patients will be followed for 5 years. ENGAGE is the largest contemporary EVAR registry for a single manufacturer’s stent, and it includes a database that can be pooled and compared with other available stent graft data, according to Dr. Böckler.
Of note, the registry participants include a challenging patient population: 16% had symptomatic abdominal aortic aneurysms, 10.6% were classed as ASA (American Society of Anesthesiologists) IV (having severe systemic disease that is a constant threat to life), and 10.5% were female patients with narrow access arteries.
Although more patients and additional follow-up are needed to prove long-term efficacy, these 2-year findings demonstrate that real-world EVAR practice with the Endurant stent graft system provides very good and durable results, Dr. Böckler said. "EVAR is getting better with the new-generation devices."
Dr. Böckler has served as a consultant, advisory board member, or speaker for Endologix, Endomax, Gore, Medtronic, Siemens, and Maquet. He has received research or grant support from Gore, Maquet, Medtronic, and Siemens.