torediscovery.blogg.se

Known causes of orthostatic tachycardia must be considered and excluded.

The evaluation of a patient suspected to have POTS first requires a detailed history and physical examination. Patients with a postviral onset may have a better chance of symptom resolution than patients with more hyperadrenergic features, who may require therapy indefinitely. The prognosis for adolescents diagnosed with POTS is more favorable for recovery than for newly diagnosed adults, but long-term follow-up data is lacking. Because POTS usually presents between 13 and 50 years of age, the impact on productivity at work and lifestyle can be devastating. The exact prevalence of POTS is not known, with estimates that range from 500,000 to 3,000,000 patients in the United States, and a female:male ratio of 4–5:1. In young children, a higher HR threshold (≥40 bpm) should be used, since healthy younger children have a greater physiological orthostatic tachycardia. A diagnosis of POTS is currently based on an increase in heart rate (HR) of ≥30 bpm, within 10 min of assuming an upright posture (standing or upright tilt), in the absence of orthostatic hypotension. Postural tachycardia syndrome (POTS) was first officially described as a syndrome by Schondorf and Low in 1993 and was most recently defined in 2011. Treatment of POTS includes exercise and medications directed at decreasing sympathetic tone or increasing blood volume. In contrast, patients with VVS experience delayed symptoms and abrupt drops in BP and HR and are more likely to lose consciousness. In patients with POTS, during upright tilt, sympathetic tone increases, there is an early and sustained tachycardia, and patients complain of presyncope without frank syncope. Nevertheless, differences emerge during head up tilt table testing. Considerable clinical overlap exists between POTS and vasovagal syncope (VVS) with patients experiencing similar orthostatic symptoms related to insufficient adaptation to blood volume shifts during upright posture. Because it affects mainly women between 13 and 50 years of age, the impact on productivity at work and lifestyle can be devastating. The prevalence of POTS has been estimated as 500,000–3,000,000 patients in the USA.

Postural tachycardia syndrome (POTS) is a syndrome defined as an increase in heart rate (HR) of ≥30 bpm within 10 min of assuming an upright posture in the absence of orthostatic hypotension (decrease in blood pressure (BP) >20/10 mmHg).