Postural Tachycardia Syndrome (POTS)

This chapter describes postural tachycardia syndrome (POTS) is a syndrome of orthostatic tachycardia associated with symptoms of cerebral hypoperfusion and autonomic activation. POTS is best considered a condition rather than a disease so that the same patient may or may not fulfill criteria at different times. There is considerable heterogeneity. Some of the disparate reports likely relate to different phenotypes, with different underlying mechanisms. Onset of POTS was often postviral and peripheral autonomic denervation was manifest as loss of sweating on QSART and thermoregulatory sweat test distally. Adrenergic denervation was evident from loss of vasoconstrictor reflexes during the Valsalva maneuver. A variety of approaches have been used to alleviate symptoms in POTS. All patients need volume expansion and a high salt or high fluid regimen. Certain drugs appear to be beneficial, at least temporarily. The most widely used drugs are midodrine, propranolol, and fludrocortisone. Other measures used include body stockings and physical counter maneuvers. Medications that are commonly used include beta-blockers, midodrine, and fludrocortisones.