Published Online
on February 7, 2005

A more recent version of this article appeared on February 22, 2005

This Article Full Text (PDF) All Versions of this Article: 111/7/839    most recent 01.CIR.0000155613.20376.CAv1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Goldstein, D. S. Articles by Sharabi, Y. Search for Related Content PubMed PubMed Citation Articles by Goldstein, D. S. Articles by Sharabi, Y. Related Collections Biochemistry and metabolism Autonomic, reflex, and neurohumoral control of circulation Other Vascular biology Other diagnostic testing

Submitted on June 16, 2004
Revised on November 2, 2004
Accepted on November 5, 2004

Neurocirculatory Abnormalities in Chronic Orthostatic Intolerance

David S. Goldstein MD, PhD^*, Basil Eldadah MD, PhD, Courtney Holmes CMT, Sandra Pechnik RN, Jeffrey Moak MD, and Yehonatan Sharabi MD

From the Clinical Neurocardiology Section, NINDS, National Institutes of Health, Bethesda, Md

^* To whom correspondence should be addressed. E-mail: goldsteind{at}ninds.nih.gov.

Background--Chronic orthostatic intolerance (COI) occurs in postural tachycardia syndrome (POTS) and in some individuals with repeated neurocardiogenic syncope/presyncope (NCS), without POTS. This study addressed whether patients with COI and POTS or NCS have neurocirculatory abnormalities during supine rest.

Methods and Results--Adult patients referred for COI who had POTS (n=90, mean±SEM age 40±1 years, 86% women) or NCS (n=36, 41±2 years old, 78% women) underwent measurements of plasma levels of catecholamines and forearm hemodynamics. Comparison data were obtained from 32 age- and gender-matched normal volunteers (39±2 years old, 81% women). The POTS group had a relatively fast mean heart rate (79±2 bpm) during supine rest compared with the NCS group (69±1.6 bpm, P=0.03) and normal volunteers (66±3 bpm, P=0.0004). The POTS group also had higher mean arterial norepinephrine (1.61±0.11 nmol/L, n=37) and epinephrine (0.39±0.03 nmol/L, n=37) concentrations than the NCS group (1.03±0.12 nmol/L, n=20, P=0.0012; 0.21±0.03 nmol/L, n=20, P=0.0005) and normal volunteers (1.13±0.11 nmol/L, n=20, P=0.006; 0.17±0.03 nmol/L, n=15, P=0.0001). The NCS group had higher mean forearm vascular resistance (52±6 U) than the POTS group (36±2 U, P=0.003).

Conclusions--Overall, POTS features increased heart rate and sympathetic nervous and adrenomedullary hormonal system outflows during supine rest. Increased sympathetic outflow may contribute to the relative tachycardia in POTS. NCS features forearm vasoconstriction during supine rest but not sympathoneural or adrenomedullary activation.

Key words: syncope • nervous system, sympathetic • tachycardia • norepinephrine • epinephrine

This article has been cited by other articles:

				E. M. Garland, S. R. Raj, B. K. Black, P. A. Harris, and D. Robertson The hemodynamic and neurohumoral phenotype of postural tachycardia syndrome Neurology, August 21, 2007; 69(8): 790 - 798. [Abstract] [Full Text] [PDF]

				E. M. Garland, B. K. Black, P. A. Harris, and D. Robertson Dopamine-beta-hydroxylase in postural tachycardia syndrome Am J Physiol Heart Circ Physiol, July 1, 2007; 293(1): H684 - H690. [Abstract] [Full Text] [PDF]

				A K Agarwal, R Garg, A Ritch, and P Sarkar Postural orthostatic tachycardia syndrome Postgrad. Med. J., July 1, 2007; 83(981): 478 - 480. [Abstract] [Full Text] [PDF]

				G. Jacob, E. M. Garland, F. Costa, C. M. Stein, H.-G. Xie, R. M. Robertson, I. Biaggioni, and D. Robertson {beta}2-Adrenoceptor Genotype and Function Affect Hemodynamic Profile Heterogeneity in Postural Tachycardia Syndrome Hypertension, March 1, 2006; 47(3): 421 - 427. [Abstract] [Full Text] [PDF]

				E. M. Garland, R. Winker, S. M. Williams, L. Jiang, K. Stanton, D. W. Byrne, I. Biaggioni, I. Cascorbi, J. A. Phillips III, P. A. Harris, et al. Endothelial NO Synthase Polymorphisms and Postural Tachycardia Syndrome Hypertension, November 1, 2005; 46(5): 1103 - 1110. [Abstract] [Full Text] [PDF]

				R. Schondorf, J. Benoit, and R. Stein Cerebral autoregulation is preserved in postural tachycardia syndrome J Appl Physiol, September 1, 2005; 99(3): 828 - 835. [Abstract] [Full Text] [PDF]

				K. Jáuregui-Renaud, J. A. G. Hermosillo, J. L. Jardón, M. F. Márquez, A. Kostine, M. A. Silva, and M. Cárdenas Cerebral blood flow during supine rest and the first minute of head-up tilt in patients with orthostatic intolerance Europace, January 1, 2005; 7(5): 460 - 464. [Abstract] [Full Text] [PDF]