I believe it is being done for stenosis. What about regurgitation. If not, is it expected that this procedure will be used for regurgitation in the near future?
Offhand, I'd expect it to be MORE appropriate for prolapse/regurg than for stenosis. In the former case, you might be starting with a full-sized opening, while something's got to be done to fix the stenosis (stent it, "ream it out"?) before a new valve will solve the problem. (You don't normally fix a constriction in a tube by slipping something inside it!)
Not to highjack this, just a note, some companies are specifically tageting replacing their own tissue valves this way (that wear out over time), which is easier as they know exactly what is in their valve.
As I understand the proceedure a balloon is used to crush the old valve and make the opening wider then the new valve is expanded and deployed. I also read in one of Adam Picks news letters that it is being tested for those who already have a tissue replacement that is failing.