A heart attack, formally called a Myocardial Infarction, is the result of a blockage of blood flow (O2) in one of the coronary arteries to the myocardium (heart muscle) . This results initially in ischemia (recoverable, mild pain and shortness of breath ), progresses to injury (still recoverable, pain and definite symptoms of a heart attack) and finally into necrosis (actual death of the myocardial tissue, this is completely non-reversible!!!)....The tissue dies, No re-growth, recovery at all. There are possible interventions to decrease the damage (such as aspirin), but there is nothing at all that can be done once the acute Myocardial Infarction has resulted in necrosis.... Hope this helps!!!!!!