EVEREST II Pivotal Study High Risk Registry (HRR)

The EVEREST II HRR is a single-arm prospective, multicenter clinical trial enrolling high surgical risk patients of the EVEREST II study (NCT00209274). Patients were considered high surgical risk if either their Society of Thoracic Surgery (STS) predicted operative mortality risk was ≥ 12%, or the surgeon investigator determined the patient to be high risk (≥ 12% predicted operative mortality risk) due to the presence of, at a minimum, one of the following pre-specified risk factors: * Porcelain aorta or mobile ascending aortic atheroma * Post-radiation mediastinum * Previous mediastinitis * Functional MR with ejection fraction (EF) \< 40% * Over 75 years old with EF \< 40% * Prior re-operation with patent grafts * Two or more prior chest surgeries * Hepatic cirrhosis * Three or more of the following STS high risk factors: i. Creatinine \> 2.5 mg/dL ii. Prior chest surgery iii. Age over 75 iv. EF \< 35% Upon completion of enrollment in the HRR, a process was initiated to ensure patient consent to participate in a Concurrent Control (CC) group was in place. Patients were identified to determine survival through 12 months with current standard of care treatment.CC patients were derived from a cohort of patients screened for enrollment in the HRR,yet did not enroll. All patients had moderate-to-severe (3+) or severe (4+) MR based on transthoracic echocardiography (TTE). To be considered eligible for inclusion in the CC group, the patient had to be classified as high surgical risk using the same criteria used for the HRR. Upon follow-up with the clinical sites, it was determined that some of the initially identified patients with moderate-to-severe (3+) or severe (4+) MR met the criteria for high surgical risk. Of these patients, some were not included due to; lack of Institutional Review Board (IRB) approval at the site, lack of informed consent and unable to be contacted. The remaining patients make up the CC group.