Asymptomatic Degenerative Mitral Regurgitation: A Review

Importance Most patients with severe degenerative mitral regurgitation (DMR) are likely to require surgery, but years can pass until there is a clear indication for it. The timing of mitral valve surgery for asymptomatic patients with severe DMR is controversial, and current guidelines are limited because they are based on nonrandomized studies and expert opinion. Observations In this narrative review, a decrease in left ventricular ejection fraction and an increase in left ventricular end-systolic diameter are adverse signs in the context of mitral regurgitation. Consequently, serial echocardiography is essential. However, measurements may be imprecise, and the evidence regarding the association with outcome in asymptomatic patients is inconsistent. Mitral valve repair is the preferred surgical approach; however, repair rate, durability, and outcomes vary between centers, rendering decision-making in an asymptomatic patient with DMR even more challenging. The use of natriuretic peptides, stress testing, cardiac magnetic resonance imaging, and myocardial strain imaging can aid in risk stratification and optimization of the timing of mitral valve surgery in an asymptomatic patient. Conclusions and Relevance Management of asymptomatic patients with DMR requires a comprehensive approach that goes beyond the guidelines. Close follow-up and the use of multiple modalities are recommended. Knowledge of surgical options, experience, and outcomes is important when an intervention is considered.