POTS/Pericarditis

Is Postural Orthostatic Tachycardia Syndrome ever dangerous?

Could it contribute to shock, ischemia, etc. if a vasodilator medication or vasodilating medical condition is present?

Also, how sensitive is Cardiac MRI for detecting pericarditis?

If the pericarditis were treated with an NSAID or if elevated levels of adrenal hormones (cortisol, etc.) were present due to stress, could this mask the pericarditis on MRI?

Thanks!