There are no dangerous heart issues. There are a miniscule amount of heart arrythmia's due to long term use of many years. Typically it would be used for 5 days with Covid 1984. It is safer than aspirin. It's available over the counter in much of the world.
Half the world are using it; the half with low fatality.
In the US there were 5.6 million prescriptions in 2017. No heart issues.
Standard of care treatment for several hundred thousand US lupus patients.
Approved in 1955, and on the WHO's list of Essential Medicines.
It is certainly a helluva lot safer than Remdesivir. And of a helluva lot more effective.
And maybe one thousandth of the price.
That's one reason it was viciously villified, and the other is that it would render any vaccine almost superfluous.
If it didn't work, then there would be no need to suppress it.