What can cause pots disease (postural orthostatic tachycardia syndrome)?

Adrenergic stimulati: Abnormal and excessive secretion of catecholamines due to sympathetic nervous system stimulation secondary to changes in position (due to gravity effects on circulating intravascular volume). This unchecked catecholamine surge causes a stimulation of heart rate.

Unclear: The exact cause of pots is not known. One theory is that it occurs after a viral infection, even one that is very minor.