Getting such health problems after covid vaccination is rarely caused by the vaccinations.
The fact that heart attacks (myocarditis or pericarditis) occurs after vaccination does not mean that the vaccine is always the cause. In my country 3 suspected death occurred.
(18 million people in NL)
Studies show that the risk of myocarditis and pericarditis due to a COVID-19 infection is larger than the chance of getting heart problems after a covid vaccination.
Cancer is not known at all as a cause of the vaccination.
Lareb is a trustworthy and independent research institute in NL. This page

gives an overview of all problems that occurred in the Netherlands (in Dutch, you can easily translate it with Google or AI):
https://www.lareb.nl/bijwerkingen-coronavaccins
Page on heart problems after covid vaccination:
https://www.lareb.nl/vaccin-kennis-pagina/Myocarditis-en-pericarditis-na-coronavaccinatie