ENGAGE Analysis Supports Medtronic's Endurant Stent Graft for EVAR in Short and Standard Neck Lengths

April 29, 2015—Medtronic plc announced that Prof. Hence Verhagen, MD, presented an analysis of results from the postmarket global ENGAGE registry at the Charing Cross International Symposium being held April 28 to May 1 in London, United Kingdom. The ENGAGE registry, which is evaluating Medtronic’s Endurant stent graft system used for endovascular repair (EVAR) of abdominal aortic aneurysms (AAA) in real-world clinical practice, showed that the device delivered consistently strong results in patients with short and standard neck lengths who were enrolled in the global ENGAGE registry.

The Endurant AAA stent graft system is indicated for neck lengths of at least 10 mm, depending on the device’s regional labeling for angulation threshold (60º in the United States; 75º in Europe and other countries that recognize the CE Mark).

According to Medtronic, Prof. Verhagen’s presentation focused on the influence of neck length on patient outcomes through 4 years of follow-up across a variety of measures, including type I endoleaks, secondary procedures, main body migration, and aneurysm rupture. The company noted that neck length—the span of healthy aortic tissue between the top of the aneurysm and the lowest renal artery—determines how much of a landing zone is available for the proximal end of the stent graft and is the single anatomical characteristic that most limits patient eligibility for standard EVAR of AAAs.

Prof. Verhagen’s analysis studied a total of 1,237 patients from the ENGAGE registry, including 137 patients with a short neck, defined as 8 to 15 mm in length, and 1,100 patients with a standard neck of 15 mm or greater. Although short necks generally make endovascular treatment more challenging, this analysis of ENGAGE registry patients—all of whom received EVAR with the Endurant AAA stent graft system—found no significant difference in outcomes between the two groups.

Delivery and deployment was successful in 99.4% of the patients with a standard neck and in 100% of the patients with a short neck (P = .35). The uncorrected type I endoleak rate was 1.3% for patients with a standard neck and 0% for patients with a short neck (P = .18). 

At follow-up, there were no significant differences between the two groups in terms of type I endoleaks and, more specifically, type Ia endoleaks. Through 4 years, the two groups showed similar results in terms of secondary endovascular procedures, ruptures, or conversions to open repair, and no main body migrations were reported in any of the patients.

In Medtronic’s announcement, Prof. Verhagen commented, “While neck length remains an important consideration for EVAR of AAAs, data from the ENGAGE registry show that the Endurant AAA stent graft system can address patients with short and standard necks equally well. In light of these findings, EVAR using fenestrated or branched stent graft systems should be limited to patients with especially short necks coupled with other anatomical challenges. The findings also support offering standard EVAR with the Endurant system to a broad set of patients with the appropriate anatomy.” Prof. Verhagen is chief of vascular surgery at Erasmus Medical Center in Rotterdam, the Netherlands.

ENGAGE also employs a high degree of clinical rigor for a postmarket study. For example, all data undergoes independent review and verification by investigators, routine site monitoring ensures data quality and consistency, protocol endpoints are 100% monitored, and major adverse events through 30 days and all deaths through 5 years are adjudicated by an independent clinical events committee, noted the company.

Daveen Chopra, Vice President and General Manager of the Aortic business unit in Medtronic’s Aortic and Peripheral Vascular division, stated in the company’s press release, “The ENGAGE registry demonstrates our unmatched commitment to clinical research on endovascular aortic repair. With 10-year follow-up planned for all enrolled patients, ENGAGE represents the most robust long-term evaluation of any stent graft ever undertaken.”