Commentary: The challenges of propensity score matching in cardiac surgery.

The advent of transcatheter valve technology for structural heart disease has led to heightened scrutiny of outcomes following surgical valve replacement. Here, we review a manuscript by Tsubota et al. in the Journal of Cardiac Surgery detailing a single-center, retrospective cohort study of patients undergoing mitral valve replacement from 2007 to 2018. While outcomes appear to be excellent, these results should be carefully interpreted in light of limited data regarding the propensity score match methodology utilized.