It annoys me if they knew this was a potential side effect then more care should of been taken to make sure those who were physically active weren't faced with this side effect.

Of course those that don't do much won't feel the effects of it but those who do work out would be unaware that what they are use to doing their heart currently can't keep up with, and even if the rest of their body is physically able to handle the stress of the physical activity, their main component, the heart end up breaking down.

study