title: [Postural tachycardia syndrome].
abstract: Erect posture could be a source of diverse chronic symptoms usually referred as orthostasis intolerance. Increasing number of patients suffering from orthostatic syndromes is recognized. Characterization and distinction of these orthostatic syndromes are based on the clinical presentation; including the typical history of orthostasis intolerance, and the unique hemodynamic responses on assuming upright posture. The diagnosis of postural tachycardia syndrome (POTS) requires orthostatic heart rate acceleration in excess of 120 beat/min, or an absolute increase of > or = 30 beat/min, in the absence of significant orthostatic hypotension. Subjects with POTS often exhibit more widespread symptoms of autonomic dysregulation. The diagnosis of inappropriate sinus tachycardia (IST) is based on the presence of resting tachycardia defined by pulse rate of > or = 100 beat/min, or a heart rate acceleration to same range in response to minimal stress, or activity. For the illustration of the difficulties in differentiation between these overlapping syndromes the authors present a case with POTS. The unique features of the presented case are the extreme orthostatic tachycardia (170/min), and the unexpected therapeutic effect of sinus node radiofrequency modification. We suggest a relationship between the peak orthostatic heart rate and the therapeutic value of sinus node modification.
authors.affiliation: Szegedi Tudományegyetem, Szent-Györgyi Albert Orvos- és Gyógyszerésztudományi Centrum, Altalános Orvostudományi Kar, II. Belgyógyászati Klinika és Kardiológiai Központ Belgyógyászati Intenzív Osztály, Szeged.
authors.forename: Attila
authors.initials: A
authors.lastname: Makai
authors.forename: Tamás
authors.initials: T
authors.lastname: Tahin
authors.forename: Tamás
authors.initials: T
authors.lastname: Simor
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Csanádi
authors.forename: László
authors.initials: L
authors.lastname: Rudas
mesh_terms: D000328:Adult; D017115:Catheter Ablation; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D011187:Posture; D012849:Sinoatrial Node; D013577:Syndrome; D013616:Tachycardia, Sinus / Q000175:diagnosis* / Q000503:physiopathology* / Q000628:therapy; D018667:Tilt-Table Test