The source it gives for the mortality of myocarditis is a paper titled "A clinical trial of immunosuppressive therapy for myocarditis" I.e. they were testing a possible treatment. The conclusion was "Our results do not support routine treatment of myocarditis with immunosuppressive drugs."

Referencing this as though it's the true mortality rate is woefully misleading. This is the mortality rate when using this experimental treatment.

In regards to the cardiac arrests and ambulance calls, it seems that the graph almost exactly follows the baseline, except for the two heatwaves. It doesn't say what the baseline is - I guess 2020 figures?

Edit: on further inspection - figures 1a,b,c are from a paper[1] and are showing an increase in cardiac arrest, unconsciousness, e.t.c. however this article ignores 2 graphs from the paper which show a decrease in chest pain and decrease in breathing difficulty, both of which are myocarditis symptoms.

I think this article is wilfully misleading.

[1] https://assets.publishing.service.gov.uk/government/uploads/...