Medtronic begins enrolment in feasibility study of Valiant Mona LSA branch thoracic stent graft system


Medtronic has announced the start of a new feasibility study to evaluate the safety and effectiveness of the Valiant Mona LSA branch thoracic stent graft system, an investigational medical device designed to enable a completely endovascular solution for aortic aneurysms encroaching on the left subclavian artery.

Cleveland Clinic cardiothoracic surgeon Eric Roselli successfully completed the first implant in the study. He serves as the study’s national primary investigator and receives consulting fees and honoraria for teaching from Medtronic.

“Thoracic aortic aneurysms involving branch vessels such as the left subclavian artery can be particularly challenging to treat,” Roselli said. “The use of an off-the-shelf stent graft system with a built-in branch has the potential to simplify this challenge by eliminating the routine requirement for surgical left subclavian artery bypass.”

The study aims to enrol 24 subjects at up to seven sites in USA. The purpose of the study is to characterise the safety and effectiveness of the investigational device acutely and at 30 days.

Coverage of the left subclavian artery during endovascular repair of thoracic aortic aneurysms proves necessary in about 40% of cases and is associated with a higher rate of neurological complications, according to published reports in peer-reviewed medical journals. As a result, the Society for Vascular Surgery suggests routine revascularisation of the left subclavian artery in elective cases where achievement of an adequate seal zone for the stent graft requires coverage of the left subclavian artery.

Based on the Valiant Captivia thoracic stent graft system, which has been used to treat approximately 50,000 patients worldwide over the last 10 years, the Valiant Mona LSA system consists of two pieces—a main graft for placement in the aneurysmal segment of the aorta, and a branch graft for placement in the left subclavian artery. In their deployed state, the system’s two pieces fit together to exclude the aneurysm and maintain patency of the artery. The main graft features a tapered opening, or cuff, which is oriented toward the left subclavian artery. The branch graft fits inside the cuff and terminates in the artery.

“The start of this study represents another step forward in our efforts to develop standardised stent graft systems for the treatment of aortic disease involving branch vessels,” said Daveen Chopra, vice president and general manager of the Aortic franchise in Medtronic’s Aortic and Peripheral Vascular business.

The Valiant Mona system has previously been studied as part of an early feasibility pilot programme for medical devices initiated by the US Food and Drug Administration (FDA) in 2012. It was one of nine devices selected by the FDA for the programme. Results from this previous evaluation were presented at the VEITHsymposium.

Use of the Valiant Mona branch thoracic stent graft system is limited to the current study approved by the US Food and Drug Administration (FDA) under an investigational device exemption.