To evaluate the safety and performance of the Mi-thos® Mitral Heart Valve with the Mi-thos® Transcatheter Delivery System.

The Mi-thos® study is an multicenter, single-arm, prospective, safety and performance clinical study.

Inclusion Criteria:

• Severe mitral valve regurgitation ≥ 3+;
• High surgical risk fot open mitral valve surgery;
• Age ≥ 65 years old;
• Life expectancy > 12 months;
• As assessed by multidisciplinary cardiac team, patients who are not eligible for surgery;
• Patients sign an informed consent form.

Exclusion Criteria:

• Previous cardiac mitral valve surgery;
• Active infections requiring antibiotic therapy;
• Clinically significant untreated Coronary Artery Disease (CAD);
• Pulmonary hypertension （Pulmonary systolic pressure > 70 mmHg）;
• Patients with severe right heart failure;
• Left ventricular ejection fraction <25%;
• Diagnosis of hypertrophic cardiomyopathy, restrictive cardiomyopathy, constrictive pericarditis;
• Dialysis patient;
• Patients with severe coagulopathy;
• Patients with contraindications to anticoagulant drugs;
• Patients with stroke or transient ischemic within 30 days;
• Echocardiography found any intracardiac mass, left ventricle or atrial thrombus;
• Patients who require surgery or interventional therapy for other valvular lesions;
• Patients with severe macrovascular disease requiring surgical treatment;
• Patients with more than 70% of carotid stenosis;
• To be allergic to contrast agents, nickel-titanium memory alloys or bovine-derived products;
• Patients with severe neurological disorders affecting cognitive ability;
• Patients with severe thoracic deformities.