Postural Orthostatic Tachycardia Syndrome Dysautonomia Orthostatic Intolerance Supine Position Tachycardia Cerebral Blood Flow Orthostatic Hypotension High Quality Content by WIKIPEDIA articles! Postural orthostatic tachycardia syndrome (POTS, also postural tachycardia syndrome, PoTS) is a condition of dysautonomia, more specifically orthostatic intolerance, in which a change from the supine position to an upright position causes an abnormally large increase in heart rate, called tachycardia. ... more »By the definition of POTS used of at the Mayo Clinic, this is not accompanied by a fall in blood pressure. Several studies show a decrease in cerebral blood flow with systolic and diastolic cerebral blood flow (CBF) velocity decreased 44 and 60%, respectively.« less