A step in the right direction, using & modifying already existing cellular capabilities. Hopefully we'll get to the point where the damage can be prevented in the first place, such as megadosing vitamin D to keep arteries flexible.
Canadian scientists have found that a protein called cardiotrophin 1 (CT1)
can essentially trick the heart into the good kind of growth, as if you exercise.
It would seem, it can be taken both after a heart attack, to induce proper heart growth and repair,
and preemptively, to gain a heart of an athlete (or at least one of someone who runs regularly),
so you'd have better cardiac blood-supply reserves and suffer less damage from an attack.
"When part of the heart dies, the remaining muscles try to adapt by getting bigger, but this happens in a dysfunctional way and it doesn't actually help the heart pump more blood," says Lynn Megeney, senior author of the study. "We found that CT1 causes heart muscles to grow in a more healthy way and it also stimulates blood vessel growth in the heart. This actually increases the heart's ability to pump blood, just like what you would see with exercise and pregnancy."
Full paper here: