Minimally invasive MV repair absolutely DOES exist!!! There are several members here who have had it. There is a surgeon in the Dallas area, Dr. William Ryan, who has done a lot of them, one on a friend of a friend with whom I now correspond.
One of our members, MaryC, had hers done by Dr. Ryan. Her sister also did. There is a member in LA, Debster913 who had a minimally invasive MV repair.
My repair, according to my surgeon, was too complicated to be done in a minimally invasive way, but definitely it does exist.
Dr. Ryan also did my husband's MV repair via a keyhole (right thoracotomy) incision, between the ribs. My husband's cardio is very impressed with the work on the valve -- and the incision is almost imperceptible.
He said that if a repair wouldn't work, he could still do a replacement via the same incision.
I asked him if he could do a side incision on me, should I ever need a re-op, and he said it was possible.
Not everyone is a candidate for a thoracotomy. Dr. Ryan said that overweight people or women with large breasts are not candidates, since the incision is right under the right breast. I believe he may have said that diabetics aren't good candidates, but don't hold me to that.
My surgeon told us that he could also do a thoracotomy, but preferred to do a full sternotomy. Said he did a lot when he started his surgical practice, but had switched to sternotomies, unless a patient specified otherwise.