“Encouraging” results with the Endurant stent graft in US trial at one year


The Endurant abdominal aortic aneurysm stent graft, from Medtronic, delivered strong results through one year of patient follow-up in the company’s US pivotal study, according to clinical data presented at VEITHsymposium on 19 November 2010.

Approved by the FDA under an investigational device exemption (IDE), the prospective study involved 150 patients at 26 US medical centres and met its primary endpoints. In the study, the Endurant system was associated with no post-operative aneurysm ruptures or aneurysm-related mortalities at one year, and there were no mortalities from any cause at 30 days.

“The clinical results with Medtronic’s Endurant stent graft system out to one year in this study are quite encouraging,” said the study’s principal investigator, Michel Makaroun, professor and chief of vascular surgery for the University of Pittsburgh School of Medicine. “Based on this data, the Endurant stent graft, with its low-profile delivery system and accurate deployment, appears to be safe and effective in the short term. It will prove to be a great addition to the currently available devices in the management of abdominal aortic aneurysms for a wide range of patients.”

The study’s primary safety and effectiveness endpoints were major adverse events at 30 days and a composite of technical and treatment success of the device at one year, respectively. Significantly for clinical practice, the study included patients with “landing zones,” or healthy aortic neck lengths, as short as 10mm, whereas most other trials of aortic stent grafts have required neck lengths of at least 15mm.

The study monitored changes in aneurysm size and stent graft migration, a concern with current endovascular treatment. Nearly half (47.1%) of the aneurysm sacs that were treated with Endurant in the study decreased in size between one month and one year post-procedure, and none of the sacs increased in size; the rest (52.9%) remained stable in size during the same time period. In addition, none of the stent grafts migrated from their original placement.

The study also monitored the occurrence and type of endoleaks, which can result in persistent blood flow into the aneurysm sac. Through one year post-implant, there were no (zero) type I or III endoleaks.

The Endurant stent graft system is currently used to treat patients with abdominal aortic aneurysms in approximately 100 countries around the world. The leading abdominal stent graft outside the United States, it received the CE mark in July 2008. The Endurant System is an investigational device in the United States, where its clinical use is limited to studies approved by the FDA. It is currently under review by the FDA for pre-market approval.