OBJECTIVE
To evaluate the prevalence and pathogenetic mechanisms of postural orthostatic tachycardia
syndrome (POTS).
PATIENTS AND METHODS
We reviewed the medical records of patients with POTS seen at the Mayo Clinic in Rochester,
Minn, from January 1, 1993, through December 31, 2003. All patients were required
to have had a full autonomic reflex screen. The results of the following additional
tests were evaluated: thermoregulatory sweat test, plasma catecholamine measurement,
serum ganglionic (α3) acetylcholine receptor antibody detection, and 24-hour urinary
sodium measurement.
RESULTS
We identified 152 patients (86.8% female; mean ± SD age, 30.2±10.3 years) with a mean
duration of symptoms of 4.1 years. The mean orthostatic heart rate increment was 44
beats/min. Half the patients had sudomotor abnormalities (apparent on both the quantitative
sudomotor axon reflex test and thermoregulatory sweat test), and 34.9% had significant
adrenergic impairment, indicating that at least half of the patients had a neuropathic
pattern of POTS. In 13.8% of patients, onset was subacute, and ganglionic acetylcholine
receptor antibody was detected in 14.6%, suggesting an autoimmune origin in at least
1 in 7 patients. Hyperadrenergic status was documented in 29.0% of patients (standing
plasma norepinephrine level ≥600 pg/mL), and at least 28.9% were presumably hypovolemic
(24-hour urinary sodium level <100 mEq/24h). The lack of correlation between urinary
sodium and standing norepinephrine levels suggests that mechanisms other than hypovolemia
accounted for the hyperadrenergic state.
CONCLUSION
Our findings suggest a neuropathic basis for at least half the cases of POTS and that
a substantial percentage of cases may be autoimmune. Hyperadrenergic and hypovolemic
correlates are likely compensatory or exacerbating.
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REFERENCES
- Idiopathic postural orthostatic tachycardia syndrome: an attenuated form of acute pandysautonomia?.Neurology. 1993; 43: 132-137
- Patterns of orthostatic intolerance: the orthostatic tachycardia syndrome and adolescent chronic fatigue.J Pediatr. 1999; 135: 218-225
- Hypovolemia in syncope and orthostatic intolerance role of the renin-angiotensin system.Am J Med. 1997; 103: 128-133
- The neuropathic postural tachycardia syndrome.N Engl J Med. 2000; 343: 1008-1014
- Excessive gravitational blood pooling caused by impaired venous tone is the predominant non-cardiac mechanism of orthostatic intolerance.Clin Sci (Lond). 1996; 90: 277-285
- Splanchnic-mesenteric capacitance bed in the postural tachycardia syndrome (POTS).Auton Neurosci. 2000; 86: 107-113
- Hypocapnia and cerebral hypoperfusion in orthostatic intolerance.Stroke. 1998; 29: 1876-1881
- Prospective evaluation of somatic and autonomic small fibers in selected autonomic neuropathies.Neurology. 2004; 62: 612-618
- Autoantibodies to ganglionic acetylcholine receptors in autoimmune autonomic neuropathies.N Engl J Med. 2000; 343: 847-855
- Autonomic nervous system function.J Clin Neurophysiol. 1993; 10: 14-27
- Quantitative sudomotor axon reflex test in normal and neuropathic subjects.Ann Neurol. 1983; 14: 573-580
- Effect of age and gender on sudomotor and cardiovagal function and blood pressure response to tilt in normal subjects.Muscle Nerve. 1997; 20: 1561-1568
- Composite autonomic scoring scale for laboratory quantification of generalized autonomic failure.Mayo Clin Proc. 1993; 68: 748-752
- Thermoregulatory sweating abnormalities in diabetes mellitus.Mayo Clin Proc. 1989; 64: 617-628
- Salt supplementation increases plasma volume and orthostatic tolerance in patients with unexplained syncope.Heart. 1996; 75: 134-140
- Pooling in chronic orthostatic intolerance: arterial vasoconstrictive but not venous compliance defects.Circulation. 2002; 105: 2274-2281
- Limb venous compliance in patients with idiopathic orthostatic intolerance and postural tachycardia.J Appl Physiol. 2002; 93: 636-644
- Microvascular filtration is increased in postural tachycardia syndrome.Circulation. 2003 Jun 10; 107 (Epub 2003 May 19.): 2816-2822
- Hemodynamic and symptomatic effects of acute interventions on tilt in patients with postural tachycardia syndrome.Clin Auton Res. 2000; 10: 29-33
- The postural orthostatic tachycardia syndrome: a potentially treatable cause of chronic fatigue, exercise intolerance, and cognitive impairment in adolescents.Pacing Clin Electrophysiol. 2000; 23: 344-351
- Autonomic nervous system dysfunction in adolescents with postural orthostatic tachycardia syndrome and chronic fatigue syndrome is characterized by attenuated vagal baroreflex and potentiated sympathetic vasomotion.Pediatr Res. 2000; 48: 218-226
- Increased sympathetic activation in idiopathic orthostatic intolerance: role of systemic adrenoreceptor sensitivity.Hypertension. 2002; 39: 173-178
- Cerebral and systemic hemodynamics changes during upright tilt in chronic fatigue syndrome.J Neuroimaging. 2003; 13: 57-67
Article info
Footnotes
This work was supported in part by the National Institutes of Health (NS32352, NS44233, NS43364, DK068055, and MO1 RR00858) and Mayo Foundation.
Identification
Copyright
© 2007 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.
