The subjects with moderate-to-severe (3+) and severe (4+) mitral valve regurgitation (MR) at high or prohibitive surgical risk will be evaluated by the study sites, and study eligibility confirmed by the echocardiographic core laboratory and eligibility committee. Those qualifying will then be treated with Dragonfly transcatheter mitral valve repair system after signing the informed consent. The follow-up will be conducted at discharge, 30 days, 6 months and 12 months after the operation. The primary endpoints are the incidence of major adverse events (MAE) at 30 days, and acute procedural success. Acute procedural success is defined as placement of one or more Dragonfly devices on the mitral valve with reduction of MR to 2+ or less. The secondary endpoints include all-cause mortality, cardiovascular mortality, incidence of serious adverse event, cardiovascular rehospitalization, NYHA functional class, mitral valve hemodynamics, acute technical success rate and device success rate at 6 months. Acute technical success is defined as no procedural mortality, successful in access, delivery, and retrieval of the device delivery system, and no emergency surgery or reintervention related to the device or access procedure in the catheterization laboratory. Device success is defined as no procedural mortality, proper delivery and deployment of the device, no unplanned surgical or interventional procedures related to the device, no specific device-related technical failure and or complications, function improvement of MR without significant stenosis (MR ≤ 2+) and without associated hemolysis or thrombogenesis.
To establish the safety and effectiveness of the DragonFly transcatheter mitral valve repair system in symptomatic patients with moderate to severe and severe mitral regurgitation who have been determined to be at an high risk of mortality with mitral valve surgery by the cardiac surgeon with concurrence by the local Heart Team