Perspective:

AR is the most frequent complication following TAVR, with the majority of patients having some AR following this procedure, and 12% of individuals having moderate or severe AR in the present meta-analysis. While moderate or severe AR has been demonstrated to be associated with increased mortality in multiple studies, outcomes in patients with mild AR have been less clear, although data suggest a potential risk of increased mortality. These results may be confounded by the difficulty in accurately quantifying the severity of AR following TAVR, as paravalvular AR in TAVR patients is frequently comprised of multiple eccentric jets, and accurate and reproducible assessment can be challenging due to the lack of a comprehensive standardized approach to grading post-TAVR AR. This study reported an increased prevalence of moderate or severe AR in patients treated with the CoreValve as compared with the Edwards valve, but the appearance and pattern of paravalvular AR differs between these valves, and standardized AR grading is needed to verify these findings. Further, while it is not surprising that significant acute AR can have adverse clinical consequences, it is not immediately clear why mild AR may also have this result, and there is a possibility that at least some of the observed risk associated with AR is due to this representing a surrogate for other risk factors. Given the rapidly expanding utilization of TAVR, there is a strong need for improved identification of patients at risk for AR, improvement in techniques and devices to reduce AR, and standardization of grading AR.