Can one recover from massive heart attack?

Possible but: Depend on few factors. Age, other conditions, risk factors, damage to other organs like kidney failure. Also on how fast it was treated, interventions done, complications like heart failure, arrhythmias, mitral regurgitation, ventricular thrombus/rupture and other vascular complications. After the heart attack the patient will go through a rehabilitation process with better assessment perform.

Yes but this: Is highly variable & depends on amount of permanent damage & if other organs were affected.