POTS Defined Upright posture is a fundamental human activity requiring rapid and effective circulatory and neurologic compensations in order to maintain blood pressure and consciousness. The orthostatic tachycardia syndrome is a disabling disease state described at least since 1940 and is the most common reason for referral for chronic orthostatic intolerance.
Patients are often unable to hold jobs or attend schools.
Yet, our understanding of its pathophysiology remains incomplete. An exaggerated increase in heart rate, often accompanied by hypotension in association with dizziness, nausea, palpitations, heat and fatigue in the upright position has been described under other names including the hyperadrenergic syndrome of Streeten, idiopathic hypovolemia of Fouad et al, and most recently the postural orthostatic syndrome of Low et al. There is an as yet undetermined but increasing apparent prevalence in children and adolescents. Resting tachycardia is common. Patterns of heart rate and blood pressure variation are shown in the figure and are from our paper which was the first to directly discuss POTS in the pediatric population.