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Postural orthostatic tachycardia syndrome (POTS) is one of a group of disorders that have orthostatic intolerance (OI) as their primary symptom.OI describes a condition in which an excessively reduced volume of blood returns to the heart after an individual stands up from a lying down position.n POTS, the lightheadedness or fainting is also accompanied by a rapid increase in heartbeat of more than 30 beats per minute, or a heart rate that exceeds 120 beats per minute, within 10 minutes of rising. The faintness or lightheadedness of POTS are relieved by lying down again.
Diagnostic Criteria. The current diagnostic criteria for POTS is a heart rate increase of 30 beats per minute (bpm) or more, or over 120 bpm, within the first 10 minutes of standing, in the absence of orthostatic hypotension.1,2,3,4 In children and adolescents, a revised standard of a 40 bpm or more increase has recently been adopted.hile some of the physical symptoms of POTS overlap with the symptoms of anxiety, such as tachycardia and palpitations, POTS is not caused by anxiety. POTS patients are often misdiagnosed as having anxiety or panic disorder, but their symptoms are real and can severely limit a person's ability to function.