Some of the authors of COAPT are trying to explain this by slightly worse valvular parameters and larger heart chambers. MITRA-FR also had a slightly higher complication rate.
However, my personal feeling is we need a third trial.
From the article:
A smaller study in France with similar patients failed to find a benefit for the MitraClip.
The study from France:- https://www.nejm.org/doi/full/10.1056/NEJMoa1805374
But that research included many patients with less severe valve problems, the procedure was not performed as adeptly, and the patients’ medications were not as well optimized as in the new study.
In the new trial, 614 patients with severe heart failure in the United States and Canada were randomly assigned to receive a MitraClip along with standard medical treatment or to continue with standard care alone. ------------------
Bottom line it seems like this is a net positive considering the fact the patients were randomized. The only thing to be suspicious of is that Abbott funded the study but it does say that the data was reviewed by outside experts.