Okay, all those who got a noticeable heart condition due to the Pfizer shot have clearly f*cked up. Now, the most important question,
This is hard to tell, there are no systematic data about this collected, because officials want to cover up, but not clarify.
Generally, keep healthy and in shape (reduce waight if needed), eat high-quality food and sleep enough. No alcohole and nicotine, etc. and lot of fresh air and good social contacts.
And supplement VitD if you have not enough sun exposure.
By the way, how come your user name is a German word? Is there a history behind?
Yes, actually, as I was listening to Rammstein in my teenage years, it caught my attention - primarily by the sounding. I translated every lyrics they had. And then it stuck for years. I now think that it reflects my existential condition, philosophically)
I wish there was something less ridiculous to tell!