[Postural orthostatic tachycardia syndrome].

Postural orthostatic tachycardia syndrome (POTS) is a condition where the patient experiences tachycardia (a rise in heart rate of at least 30 beats per minute, 40 in people between the ages of 12 and 19) upon assuming the upright position, in the absence of orthostatic hypotension (a fall in systolic blood pressure of more than 20 mmHg). The majority of patients are young women. Symptoms are experienced frequently during standing, and include dizziness, fatigue, palpitations, tremulousness, blurred vision and sometimes syncope - although presyncope is more common. The diagnosis requires that symptoms have been present for at least six months and lack another medical explanation. The pathophysiology is believed to be multifactorial; peripheral sympathetic denervation, excessive sympathetic drive, hypovolemia and deconditioning have been reported in POTS. Patient education is fundamental in the management of POTS, including information regarding symptoms and exacerbating factors as well as methods for increasing arterial pressure. Exercise is believed to be effective. Several drugs can be used to relieve symptoms, although none of them are licensed for the treatment of POTS. We describe a case that illustrates that POTS can be debilitating, which requires awareness of the condition among clinicians.