The catherization will give them a much more accurate view of all the major arteries in your heart and they can determine what will need to be
done. Generally, blockages less than 50% are left alone but need to be
monitored, up to
75%-80% usually can be stented, 100% blockages generally require bypass. As for the damage to the heart, it may not be a blockage, it could be scare tissue damage or an electrical impulse issue, that's why they are doing the cath.