Midterm Data Demonstrate Durable Outcomes With Medtronic's Endurant AAA Stent Graft

December 9, 2014—Medtronic, Inc. announced that the latest results from two clinical studies for endovascular repair of abdominal aortic aneurysms (AAA) demonstrated that the company’s Endurant AAA stent graft system continues to deliver durable, consistent, and proven outcomes.

The latest results on the Endurant AAA stent graft system’s midterm performance come from the United States investigational device exemption (IDE) study that led to the device’s approval by the US Food and Drug Administration in 2011 and the international ENGAGE registry that was initiated after receipt of European CE Mark approval in 2008.

The United States IDE study enrolled 150 patients at 26 centers with strict eligibility criteria compared to the international ENGAGE registry, which has enrolled more than 1,200 patients at 79 sites across six continents with very few exclusion criteria––and, as a result, more complex baseline characteristics, including 17.8% whose AAA features placed them outside thedevice’s instructions for use.

According to Medtronic, 4-year follow-up for all 150 patients enrolled in the IDE study and for the first 500 patients enrolled in the international ENGAGE registry has been completed. Three-year follow-up for all 1,263 patients in the ENGAGE registry has been completed.

Outcomes for these three patient cohorts were presented recently at the VIVA 2014: Vascular InterVentional Advances meeting held November 4–7, 2014, in Las Vegas, Nevada and the 41st VEITHsymposium held November 18–22, 2014, in New York, New York.

As summarized by Medtronic, 4-year results for all 150 patients in the United States IDE study include a 99.2% rate of freedom from aneurysm-related mortality and a 90% rate of freedom from secondary intervention. In addition, 98% of the patients’ aneurysm sacs were stable or had decreased in diameter by > 5 mm at 4 years of follow-up. At 4 years, none of the patients (0%) had experienced a type I/III endoleak or a main body migration.

The company advised that 4-year results for the first 500 patients in the ENGAGE registry are consistent with those for all patients in the United States IDE study, despite the differences in eligibility criteria and baseline characteristics. They include a 98.4% rate of freedom from aneurysm-related mortality, and an 87.3% rate of freedom from secondary intervention.

Similarly, 3-year results for all 1,263 patients in the ENGAGE registry include a 98.5% rate of freedom from aneurysm-related mortality and an 89.5% rate of freedom from secondary intervention. In addition, 91% of the patients’ aneurysm sacs were stable or had decreased in diameter by > 5 mm at 3 years of follow-up. At 3 years, type I/III endoleaks had occurred in 1.5% of the patients and no patients experienced main body migration (0%).

With follow-up now planned for 10 years, the ENGAGE registry promises to be first in providing the longest-term performance data on a single stent graft.

Edward Woo, MD, who presented the data on Endurant at the VIVA 2014 meeting, commented in Medtronic’s press release, “Aneurysm-related mortality, secondary interventions, and changes in sac diameter are three critically important measures of stent graft performance. Judging from the latest results from two high-quality studies, the impressive performance of the Endurant stent graft system has proven to be remarkably durable and consistent on these and other important measures across a wide range of patients and operators.” Dr. Woo is director of the MedStar Regional Vascular Program, and Chairman of Vascular Surgery and Professor of Surgery at Georgetown University in Washington, DC.