Actually having heart issues is a very compelling reason to get vaccinated! If you catch COVID you're much more likely to get complications due to the stress on organs. It's those other health issues that get worse and could ultimately see you in ICU or a coffin.
The official COVID death toll is now just shy of 5½ million, but due to undercounting & poor statistics (especially in 3rd world countries) the real toll is estimated to be 2 or 3 times that (i.e. between 10 to 17 million).
On the other hand, almost 9 billion doses of COVID vaccines have been administered so far (currently about 33 million per day) and the number of complications arising is miniscule by comparison. Every medication & vaccine will have some type of side-effect (and some are potentially harmful) but I don't understand individuals would rather risk their health (and their family, friends & work colleagues) by taking their chances with COVID instead.