Mitral Loop Cerclage(MLC) for Reducing Functional Mitral Regurgitation

Inclusion Criteria: * NYHA(New York Heart Association) Class III - IV, and symptomatic severe functional MR by 2014 ACC/AHA guideline in spite of optimal medical treatment. (For optimal medical treatments, ①ACE inhibitor or angiotensin receptor blocker ②β-blocker ③ aldosterone antagonists should be given for at least 3 months unless the subject has contraindication for each drug) Exclusion Criteria: * Primary Mitral Regurgitation * LV ejection fraction lower than 25% * Creatinine ≥2.0 mg/dL * Anomaly of Coronary Sinus * Pre-existing devices in coronary sinus such as Implantable Cardioverter Defibrillator and Pacemaker * 2:1 Atriventricular AV block or higher AV block and ventricular tachycardia * Subjects with functional MR who need CABG or AVR performed * Subjects who have functional MR caused by aortic valve disease * Subjects who have uncontrollable hyperthyroidism * Subjects who have severe TR due to primary valve leaflet disease * Subjects who cannot be screened by cardiac CT * Subjects who have possibility of coronary artery pinching even with Mitral Loop Cerclage system judged by cardiac CT * Subjects who are unable to take anti-platelet agents * Subjects who are participated in other clinical trials within 1 month of enrollment * Subjects who have coagulation disorders * Subjects who have thrombosis and embolism * Subjects who are pregnant, or lactating, or plan pregnancy during the clinical trials * Subjects who are deemed not to be eligible in this study by physician's discretion