A corollary from this might be that getting a person with POTS to exercise may not make them no longer have POTS.
Exercise Performance in Adolescents with Autonomic Dysfunction.
Journal: J Pediatr. 2010 Aug 31. [Epub ahead of print]
Burkhardt BE, Fischer PR, Brands CK, Porter CB, Weaver AL, Yim PJ, Pianosi PT.
Department of Pediatric Cardiology and Congenital Heart Disease, University Medical Center Freiburg, Freiburg, Germany.
Abstract
OBJECTIVE: To test the hypothesis that excessive postural tachycardia is associated with deconditioning rather than merely being an independent sign of autonomic dysfunction in patients with postural orthostatic tachycardia syndrome (POTS).
STUDY DESIGN: We retrospectively analyzed records from 202 adolescents who underwent both head up-tilt and maximal exercise testing. Patients were classified as POTS if they had >/=30 min(-1) rise in heart rate (HR) after tilt-table test; and deconditioned if peak O(2) uptake was <80% predicted.
Changes in HR during exercise and recovery were compared between groups.
RESULTS: Two-thirds of patients were deconditioned, irrespective of whether they fulfilled diagnostic criteria for POTS, but peak O(2) uptake among patients with POTS was similar to patients without POTS. HR was higher at rest and during exercise; whereas stroke volume was lower during exercise, and HR recovery was slower in patients with POTS compared with patients without POTS.
CONCLUSIONS: Most patients who presented with chronic symptoms of dizziness, fatigue, or pre-syncope, were deconditioned, but, because the proportion of deconditioned patients was similar in POTS vs non-POTS groups, we conclude that HR changes in POTS are not solely because of inactivity resulting in deconditioning.
PMID: 20813382 [PubMed - as supplied by publisher]