It all depends on the timing of the revascularisation. When having a
heart attack, the blood supply is cut off from a section of
heart muscle. This muscle starts to die in a matter of minutes. Depending how soon treatment is received, determines how much muscle dies. Once it dies, the muscle never regenerates or recovers. Some of the heart muscle could have been in a state of damage, before death, and this usually recovers over a couple of months.