This is so absolutely NOT true. See my post above. Myocarditis is very treatable, the real danger is if the condition goes undiagnosed until it causes death or major damage to the heart muscle. If myocarditis is diagnosed before it causes death or permanent damage, it can be treated and very frequently has good outcomes that do not impact overall lifespan or quality of life. And as gnuguy pointed out above, myocarditis often resolves itself with no treatment if the heart is not put under major stress while it is inflamed. I would be willing to bet that a huge number of people have myocarditis at some point during their lives, possibly multiple times, and never even know it because it resolves on its own before anything bad happens or even before any symptoms appear.