Burden, treatment use, and outcome of secondary mitral regurgitation across the spectrum of heart failure: observational cohort study.

Secondary mitral regurgitation is common overall, increasing with age and associated with excess mortality. The association with adverse outcome is significant across the entire heart failure spectrum but most pronounced in those with mid-range and reduced ejection fractions. Despite these poor outcomes, surgical valve repair or replacement are rarely performed; similarly, low risk transcatheter repair, specifically in the heart failure subsets with the highest expected benefit from treatment, is seldom used. The current data suggest an increasing demand for treatment, particularly in view of an expected increase in heart failure in an ageing population.