AltaValve Pivotal Trial

Inclusion Criteria: * Age ≥ 18 years. * Symptomatic New York Heart Association (NYHA) class II-IV. * Moderate-to-severe or severe MR (3+) despite optimal guideline-directed medical therapy (GDMT) as determined by an independent Echo Core Lab. * Unsuitable for surgery and Transcatheter Edge-toEdge Repair (TEER) as determined by the local site Heart Team. Exclusion Criteria (Abbreviated List): * Inability to understand the trial or a history of non-compliance with medical advice. * Inability to provide signed Informed Consent Form (ICF). * History of any cognitive or mental health status that would interfere with participation in the trial. * Currently enrolled in any other pre-approval investigational trial (does not apply to long-term post-market trials unless these trials might clinically interfere with the current trial endpoints (e.g., limit use of trial-required medication, etc.)). * Female subjects who are pregnant or planning to become pregnant within the trial period. * Known hypersensitivity or contraindication to heparin, or warfarin without adequate alternative medications. * Known hypersensitivity to nitinol (i.e., nickel allergy) that cannot be adequately medicated. * Known hypersensitivity to contrast media that cannot be adequately medicated. * Evidence of current left ventricular ejection fraction (LVEF) ≤ 25%. * Concurrent medical condition with a life expectancy of less than 12 months. * Transcatheter aortic repair or replacement within 90 days prior to the index procedure. * Percutaneous coronary intervention (PCI) within 90 days prior to the index procedure.