Why is this study important?

The one-year data of transcatheter mitral valve replacement (TMVR) outcomes from the ENCIRCLE trial represent a meaningful step forward in the treatment of mitral regurgitation in patients who are not candidates for surgery or transcatheter repair. The ENCIRCLE trial uses the Sapien M3 system from Edwards Lifesciences.

What question was this study supposed to answer?

The population studied was elderly patients (average age 75.5) with heart failure and elevated STS risk. The study used a combined endpoint of mortality and hospitalization for heart failure. These data were compared to a benchmark of 45% which was the prespecified performance goal based on the general population risk.

What did the study show?

The all-cause mortality rates and heart failure rates in patients who received the M3 device were much lower than the benchmark of 45%. The mortality rate was 12.9% at one year, and heart failure hospitalization was 16.7%. The amount of mitral regurgitation was significantly reduced, and 95% of patients had 0 to 1+ regurgitation at 1 year. Mitral regurgitation remains a challenge to treat in patients for whom transcatheter repair is not feasible. More long-term data are needed to evaluate durability and future clinical concerns.