Postural Tachycardia Syndrome in a 28-year-old Japanese Woman

Postural tachycardia syndrome is defined as the development of orthostatic symptoms without orthostatic hypotension. We report a 28-year-old female patient with postural tachycardia syndrome who exhibited palpitation, lowgrade fever and weight loss. Evaluation of autonomic nervous system functions showed that cardiovagal function was normal. Sweat response to acetylcholine was decreased. Excessive blood pressure elevation was seen in phase IV of the Valsalva maneuver. Pathophysiologic factors in this case were considered to be α adrenergic denervation and β adrenergic hyperresponsiveness. It is important that this syndrome be widely recognized and properly diagnosed. (Internal Medicine 40: 1032-1036, 2001)