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Updated: Jun 12, 2025

Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance
Published on: March 21, 2013
Reduced Stroke Volume and Brain Perfusion Drive Postural Hyperventilation in Postural Orthostatic Tachycardia
Jacquie R Baker1,2,3,4, Anthony V Incognito3,4, Shaun I Ranada1,2
1Department of Cardiac Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
Abstract:
Postural hyperventilation has been implicated as a cause of postural orthostatic tachycardia syndrome (POTS), yet the precise mechanisms underlying the heightened breathing response remain unclear. This study challenges current hypotheses by revealing that exaggerated peripheral chemoreceptor activity is not the primary driver of postural hyperventilation. Instead, significant contributions from reduced stroke volume and compromised brain perfusion during orthostatic stress were identified. These findings shed light on our understanding of POTS pathophysiology, emphasizing the critical roles of systemic hemodynamic status. Further research should explore interventions targeting stroke volume and brain perfusion for more effective clinical management of POTS.
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