I am now of the age when hearing thst a friend or acquaintance succumbed to a heart attack is not that geeat a shock. That loss of oxygen flow to the heart- from a blood clot, an occlusion, or other trauma- is not always fatal, thank G0d. But, when the heart heals, there is scar tissue- and the heart is ‘never as good as new’. But, that may be about to change. Two different groups are trying similar techniques. A third is using a slight different concept.