Early mitral valve repair surgery versus active surveillance in asymptomatic severe primary mitral regurgitation—insights from the Dutch AMR registry

BACKGROUND: Management of asymptomatic severe mitral regurgitation (MR) is challenging. Both early mitral valve repair surgery and active surveillance with facilitated surgery are possible strategies. The DutchAMR registry compares clinical outcomes between these two strategies. METHODS: Patients were included between 2013-2019. Primary endpoints were cerebrovascular accidents (CVA), reoperations, and mortality. Facilitated surgery was defined as mitral valve repair surgery performed after developing a surgical indication during active surveillance. RESULTS: Ninety-nine patients were enrolled; 71 in active surveillance and 28 in early surgery. Over a median follow-up time of 5.1 years, 51% of active surveillance patients underwent facilitated surgery due to ESC guideline triggers. Both the early and facilitated surgery groups had one perioperative CVA. During follow-up, in the active surveillance group, 5 (7%) patients died (3 without surgery and 2 after facilitated surgery), and 3 (4%) underwent reoperations. In the early surgery group, 4 (14%) patients reached a primary endpoint, including 2 (7%) CVAs (without residual symptoms) and 2 (7%) deaths. No reoperations occurred in the early surgery group. Baseline additional testing parameters based on CPET, Holter monitoring, and CMR showed no differences between the groups. CONCLUSIONS: After 5.1 years, half of the active surveillance patients required facilitated surgery, with comparable postoperative outcomes to early surgery. Clinical endpoints were comparable between the early and facilitated surgery strategies. There were no differences in baseline additional testing parameters, suggesting no clear targets for upfront stratificatio. Thus, shared decision making weighing the different risks can be used to determine the strategy per patient.