The MITRAL II Pivotal Trial (Mitral Implantation of TRAnscatheter vaLves).

Inclusion Criteria: All Candidates must meet the following criteria: 1. \- 18 years of age or older 2. -Severe mitral annular calcification with symptomatic mitral valve dysfunction including severe mitral stenosis defined as mitral valve area (MVA) of ≤1.5 cm2, or ≥ moderate to severe mitral regurgitation, or mixed ≥ moderated stenosis and ≥ moderate regurgitation. For this study, the severity of mitral regurgitation will be graded according to the 2017 American Society of Echocardiography Guidelines: None, Trivial, Mild 1(+), Moderate 2(+), Moderate to severe 3(+), and severe 4(+). 3. \- NYHA Functional Class ≥II. 4. The heart team agrees that valve implantation will likely benefit the patient. 5. High or prohibitive risk for standard mitral valve surgery as determined by the heart team (at least one site cardiac surgeon must personally examine the subject to determine operative risk in patients presented for inclusion to ViMAC arm). NOTE: Patients not interested in mitral intervention or who are being considered for inclusion in the Natural History of Disease Registry are not required to be evaluated in person by a surgeon.) 6. The study patient has been informed of the nature of the study, agrees to its provisions and has provided written informed consent as approved by the Institutional Review Board (IRB) of the respective clinical site. 7. The study patient agrees to comply with all required post-procedure follow-up visits including annual visits through 5 years. Exclusion Criteria for ViMAC subjects (does not apply to the Natural History of Disease Registry): 1. \- The heart team considers the patient is a surgical candidate. 2. \- Mitral annulus is not severely calcified. 3. \- Myocardial infarction requiring revascularization within 30 days from procedure. 4. \- Clinically significant untreated coronary artery disease requiring revascularization. 5. Any therapeutic invasive cardiac procedure resulting in a permanent implant that is performed within 30 days of the index procedure (unless part of planned strategy for treatment of concomitant coronary artery disease). Implantation of a permanent pacemaker is not exclusionary. 6. Any patient with a balloon valvuloplasty (BMV) within 30 days of the procedure (unless BMV is a bridge to ViMAC procedure after a qualifying Echo). 7. Severe symptomatic tricuspid regurgitation (hepatic dysfunction, ascites, edema not controlled with diuretics) requiring surgery. 8. Leukopenia (WBC \< 3000 cell/mL), acute anemia (Hgb \< 9 g/dL), Thrombocytopenia (Platelets \< 50,000 cell/mL), history of coagulopathy or hypercoagulable state. 9. Hypertrophic obstructive cardiomyopathy (HOCM) with mean LVOT gradient of ≥20 mm Hg at rest or ≥50 mmHg with Valsalva. 10. Hemodynamic or respiratory instability requiring inotropic support, mechanical ventilation or mechanical heart assistance within 30 days of screening evaluation. 11. Need for emergency surgery for any reason. 12. Severe left ventricular dysfunction with LVEF \< 20%. 13. Echocardiographic evidence of intracardiac mass, thrombus or vegetation. 14. Active upper GI bleeding within 90 days prior to procedure. 15. A known contraindication or hypersensitivity to all anticoagulation regimens, or inability to be anticoagulated for the study procedure. 16. Cardiac anatomy that would preclude appropriate delivery and deployment of an Edwards SAPIEN 3/Ultra/RESILIA valve in MAC via transseptal access, including but not limited to: * Native neo mitral annulus size \< 275 mm2 or \> 810 mm2 as measured by CT scan. * Significant risk of LVOT obstruction or valve embolization as assessed by CT core lab 17. Clinically (by neurologist) or neuroimaging confirmed stroke or transient ischemic attack (TIA) within 90 days of the procedure. 18. Estimated life expectancy \<12 months due to non-cardiac conditions. 19. Expectation that patient will not improve despite treatment of mitral valve dysfunction. 20. Active bacterial endocarditis within 180 days of procedure. 21. \- Severe right ventricular dysfunction as assessed by Echo core lab 22. \- Active infection requiring antibiotic therapy (subject may be a candidate after 2 weeks of antibiotic discontinuation. 23. \- Female who is pregnant or lactating. 24. \- Participating in another investigational device study. 25. \- Aortic valve disease requiring intervention. If aortic valve intervention is required, the AVR procedure should be performed first and if the patient remains symptomatic after AVR, may be presented for consideration for inclusion in this trial. 26. \- Severe fixed pulmonary hypertension (PASP ≥70 mmHg and more than 2/3 of the systemic systolic blood pressure). 27. \- Severe chronic obstructive pulmonary disease requiring continuous home oxygen. 28. \- The patient refuses mitral valve intervention 29. \- Recent symptomatic COVID-19 infection with residual symptoms that may affect the outcomes of this trial.