If i have afib/ a genetic history of heart problems, is it safe to take pfizer/moderna being that is can cause myocarditis?

Please consult your treatment team on this one. They have a full understanding of your case. One thought to consider though. If an individual develops myocarditis when exposed to a replica of the covid spike, what do you think will happen if you get covid with the spikes and the rest of the virus. There is some evidence that wild covid causes myocarditis in some people.

The incidence of myocarditis is very low with Covid vaccine To settle your doubt have your cardiologist send you for an echocardiogram before vaccination and any symptoms develops (shortness of breath) you have a base line to compare