Abbott recently announced that it has started the US pivotal clinical study to evaluate the safety and effectiveness of its Tendyne transcatheter mitral valve replacement system to treat mitral regurgitation (MR). The first patients were treated at Via Christi Hospital St. Francis in Wichita, Kansas, and the West Virginia University Heart and Vascular Institute in Morgantown, the company said. The prospective, controlled, multicenter study, called SUMMIT, will enroll up to 1010 patients at 80 sites in the US, European Union and Canada. There will be two trial arms, surgical and non-surgical. Subjects in the surgical arm will be randomized 2:1 to Tendyne or conventional mitral valve surgery. Those in the non-surgical arm will receive Tendyne. The primary outcome measure will be a composite of all-cause mortality, cardiovascular-related hospitalizations, stroke, or mitral valve reintervention or reoperation at 1 year. Gorav Ailawadi, MD, of the University of Virginia, and Jason Rogers, MD, of the University of California, Davis, are co-principal investigators. Abbott shared data at EuroPCR 2018 in May that showed positive results from the first 100 patients treated in a global study of the Tendyne device. Results the company provided showed that, at 30 days, patients treated with Tendyne had a significant reduction in symptoms of MR and low mortality rates. "The mitral valve is known for its complex anatomy and, as a result, managing mitral regurgitation can be challenging, especially in elderly or frail patients for whom there are limited to no treatment options," Bassem M. Chehab, MD, medical director of Via Christi's structural heart program, who implanted the first patient in the study with the Tendyne valve, said in Abbott’s news release. "I'm encouraged by promising early results from the global study and excited about the potential for the Tendyne device to advance the field of transcatheter mitral valve replacement in the U.S. by providing another option for MR patients needing a minimally invasive alternative." In the news release, Abbott said that Tendyne, which is investigational, is the first and only mitral valve replacement that can be repositioned and fully retrieved, allowing the surgeon to precisely place the device during implantation. In addition to the US pivotal trial, Abbott announced that it will initiate a separate feasibility study of the Tendyne system in patients with severe mitral annular calcification.