When it came to the transcatheter aortic valve replacement (TAVR) market, the U.S. was at least five years behind Europe and other parts of the world. But in recent years the FDA has become much more collaborative and open to getting involved in early feasibility studies, as evidenced by the first U.S. patient to undergo a transcatheter mitral valve replacement (TMVR) procedure in the U.S., as part of a multicenter global feasibility study.