Mitral valve repair for ischemic mitral regurgitation: lessons from the Cardiothoracic Surgical Trials Network...

Area of Science:

• Cardiovascular Surgery
• Interventional Cardiology
• Cardiac Pathology

Background:

• Ischemic mitral regurgitation (MR) affects 30-50% of myocardial infarction patients, leading to poor prognosis.
• Current surgical options include mitral valve repair or valve replacement, with varying outcomes.
• Left ventricular remodeling and subvalvular apparatus dysfunction drive ischemic MR progression.

Purpose of the Study:

• To analyze the results of the Cardiothoracic Surgical Trials Network (CSTN) study comparing mitral valve repair and replacement for ischemic MR.
• To explore evidence-based strategies for optimizing mitral valve repair outcomes in ischemic MR patients.

Main Methods:

• Randomized trial comparing mitral valve repair (restrictive annuloplasty) with chordal-sparing valve replacement in severe ischemic MR patients.
• Concomitant coronary artery bypass grafting was performed if indicated.
• Two-year follow-up assessed recurrent MR, heart failure, and left ventricular remodeling.

Main Results:

• Mitral valve repair showed a significantly higher incidence of moderate or greater recurrent MR and heart failure at 2 years.
• No significant difference was observed in left ventricular reverse remodeling indices between repair and replacement groups.
• Valve replacement demonstrated comparable or superior outcomes regarding recurrent MR and heart failure compared to repair.

Conclusions:

• Current mitral valve repair techniques, primarily restrictive annuloplasty, may be insufficient for severe ischemic MR.
• Valve replacement with subvalvular apparatus preservation appears to offer better mid-term results.
• Future strategies should focus on pathophysiologic-guided repair, potentially combining annuloplasty with subvalvular repair techniques.