Healing an injured heart

I remember when one of my diabetic  patients tried to get in a human (adult) stem cell injection experiment in Minneapolis, but alas because of his diabetes, borderline diabetes, and a previous small stroke he was turned down.

Well, I have no idea how that one went (I believe it was mildly successful in some patients) But now the BBC reports a large study in London

LINK

The study, which will involve 3,000 patients in 11 European countries, should show whether the treatment can cut death rates and repair damaged tissue after a heart attack.
All the patients will have standard treatment to widen their narrowed arteries, which involves inserting a small tube called a stent. In addition, half the patients will have stem cells taken from their bone marrow and injected into their heart.
This will happen within days of them suffering a heart attack.

so they will be trying to fix people early after a heart attack, not later trying to repair hardened scar tissue.

It is unclear exactly how a patient's own bone marrow stem cells might help repair their heart.
Donor adult stem cells have been used successfully for decades in bone marrow transplants, but in that situation it is a like-for-like replacement.
Expecting these cells to survive in the heart and transform into specialised heart cells is a huge challenge.