Ann: Data Update on First-in-Human Study of DurAVR at NY Valves, page-2

I am neither a heart scientist nor a rocket surgeon, but noting the comment by the author, Dr Cavalcante, at the end of this summation:

"Cardiac MRI also detected asignificant left ventricular mass index regression at 6 months post-TAVR"

Expanded left ventricular mass - LVM - is not a good thing, and thus regression is a positive.

For example, to quote a report regarding heart treatment more generally ( in connection with CKD - chronic kidney disease ):
LVM regression may be a useful surrogate marker for benefits of interventions intended to reduce mortality risk in patients with CKD
From https://bmcnephrol.biomedcentral.com/articles/10.1186/s12882-022-02666-1