Comparing the Effectiveness of Repairing Versus Replacing the Heart's Mitral Valve in People With Severe Chronic Ischemic Mitral Regurgitation

Evaluation of Outcomes Following Mitral Valve Repair/Replacement in Severe Chronic Ischemic Mitral Regurgitation

People with coronary artery disease (CAD) or people who have had a heart attack may develop a leak in the mitral valve of their heart and may therefore need to undergo surgery to fix the valve. The best way to fix the mitral valve remains undetermined. This study will evaluate whether it is better for people with severe mitral valve leakage to undergo a mitral valve replacement procedure or a mitral valve repair procedure.

CAD occurs when the arteries that supply blood to the heart become blocked as a result of plaque buildup. In severe cases, CAD can cause chest pain, shortness of breath, and heart attack. After a heart attack, some people may develop a leak in the mitral valve of the heart. This condition is known as ischemic mitral regurgitation (IMR), and it can cause blood to flow backward into the heart. If left untreated, severe IMR can lead to heart failure or serious heart rhythm irregularities, known as arrhythmias. People with severe mitral valve leakage routinely undergo one of two surgical procedures to fix the mitral valve: a mitral valve repair procedure, in which a surgical ring is used to repair the valve; or a mitral valve replacement procedure, in which the damaged valve is replaced with a new one. Currently, there is no consensus in the medical community as to which procedure is more beneficial. The purpose of this study is to determine whether people with severe mitral valve regurgitation should undergo a mitral valve repair procedure or a mitral valve replacement procedure.

This study will enroll people with CAD who have severe mitral regurgitation. At a baseline study visit, participants will undergo a physical examination; blood collection; neurocognitive tests; and questionnaires regarding medical history, medication history, and quality of life. In the operating room, participants will be randomly assigned to undergo either the mitral valve repair procedure or the mitral valve replacement procedure. Blood, urine, and tissue samples may be collected from participants after the surgery; this is optional and will only be done with prior approval from participants. All participants will attend study visits at Day 30 and Months 6, 12, and 24. At each visit, participants will take part in a medication history review, a physical examination, an echocardiogram, a cardiopulmonary exercise test, neurocognitive tests, and quality of life surveys.

Inclusion Criteria:

• Chronic severe ischemic mitral regurgitation (often with tethering as a major mechanism) in the judgment of the clinical site echocardiographer, assessed by transthoracic echocardiogram. Assessment of mitral regurgitation will be performed using an integrative method (Zoghbi W. et al. J. American Society of Echocardiography. 2003:16:777-802. see appendix). Quantitative guidelines as proposed would be: ERO ≥ 0.4 cmsq. If ERO < 0.4, then the degree of mitral regurgitation will be guided by other color Doppler quantitative methods (jet area/left atrial area ratio, vena contracta, supportive criteria in an integrated fashion
• Eligible for surgical repair and replacement of mitral valve
• CAD with or without the need for coronary revascularization

Exclusion Criteria:

• Any evidence of structural (chordal or leaflet) mitral valve disease or ruptured papillary muscle
• Prior mitral valve repair
• Severe irreversible pulmonary hypertension in the judgment of the investigator
• Medically unable to undergo cardiopulmonary bypass (CPB)
• Inability to derive ERO and end-systolic volume index (ESVI) by transthoracic echocardiography
• Planned concomitant intra-operative procedures (with the exception of tricuspid valve repair, closure of patent foramen ovale [PFO] or atrial septal defect [ASD] or Maze procedure)
• Clinical signs of cardiogenic shock at the time of surgery
• Treatment with long-term intravenous inotropic therapy at the time of surgery
• ST segment elevation myocardial infarction (MI) requiring intervention in the 7 days before surgery
• Congenital heart disease (except PFO or ASD)
• Evidence of cirrhosis or liver synthetic failure
• Excessive surgical risk, as judged by the surgical investigator
• Recent history of psychiatric disease (including drug or alcohol abuse) that is likely to impair compliance with the study, as judged by the investigator
• Therapy with an investigational intervention at the time of screening, or planning to enroll in an additional investigational intervention study during participation in this study
• Any concurrent disease with a life expectancy of less than 2 years
• Pregnant