My understanding is heart damage from the shot only largely effects young people (particularly young men).
That’s what I keep reading here. Several young people under age 35 in my family had multiple shots. No one had any heart issues. That does not mean some young people did suffer adverse reactions to COVID shots. May be there were other side health issues present? Who knows. My guess is overwhelming number of young people are alive and well after the jabs. Which leads me to believe percentage of people who suffered adverse side effects may be small.