Myval transcatheter heart valves (THVs) are noninferior to SAPIEN 3 THVs at one year but have a higher risk of needing first-time pacemaker implantation, according to results from COMPARE-TAVI 1 published April 2 in The Lancet.

In this first all-comers head-to-head comparison of the SAPIEN 3 (29 mm) or SAPIEN 3 Ultra (20, 23 or 26 mm) THVs vs. the Myval or Myval Octacor THVs (20-32 mm), 1,031 patients with severe aortic stenosis scheduled for TAVI at three university hospitals in Denmark were randomly assigned to SAPIEN 3 (n=517) and Myval (n=514) THVs. Their median age was 81.6 years and 40% were women.

The primary endpoint was a composite of death, stroke, moderate or severe aortic regurgitation, or moderate or severe hemodynamic THV deterioration at one year. The prespecified noninferiority margin was 5.3%, with an expected event rate of 13%.

Results showed that the primary endpoint occurred in 13% of patients with SAPIEN 3 THVs vs. 14% patients with Myval THVs, demonstrating noninferiority of Myval THVs (risk difference, –0.9%; one-sided upper 95% CI, 4.4%; p for noninferiority = 0.019). Moreover, findings showed less moderate or severe aortic regurgitation with SAPIEN 3 THVs (1%) than with Myval THVs (4%), mainly due to paravalvular leakage (92%).

Of note, fewer first-time pacemaker implantations were required in patients treated with SAPIEN 3 (12%) than with Myval (21%) THVs at one year (p=0.0002). No difference was found in patients with TAVI-related complications or patients with successful TAVI procedures, however. At one year, patients treated with SAPIEN 3 THVs walked a median of 330 m on the six-minute walk test vs. 320 m for those with Myval THVs.

In an accompanying editorial comment, Mariama Akodad, MD, PhD, writes that future post-TAVI trials are warranted. For instance, "long-term advantages of the more recent Myval THVs over the well-established SAPIEN 3 platform requires more data, especially in a younger population for whom lifetime management of aortic stenosis is crucial."