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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.
Postural orthostatic tachycardia syndrome (POTS, also known as postural tachycardia syndrome) is a condition in which a change from the supine position to an upright position causes an abnormally large increase in heart rate, called tachycardia.ther symptoms of an orthostatic nature â occurring in response to upright posture â may accompany the tachycardia. The causes of POTS are poorly understood, and it is likely that several distinct underlying problems can lead to the symptoms of POTS.