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Updated: Jun 11, 2026
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Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance
Published on: March 21, 2013
Age-related hemodynamic changes during vasovagal syncope.
Antonio Franco Folino1, Federico Migliore, Alessio Marinelli
1Department of Cardiologic, Thoracic and Vascular Sciences, University of Padua, Italy. franco.folino@unipd.it
Autonomic Neuroscience : Basic & Clinical
|July 8, 2010
Summary
Older patients exhibit blunted sympathetic responses during tilt tests for vasovagal syncope. Younger patients show excessive sympathovagal reactions, while older individuals experience progressive vagal activity with impaired sympathetic function.
Area of Science:
- Cardiology
- Autonomic Nervous System Physiology
Background:
- Vasovagal syncope is a common cause of syncope.
- Age-related differences in hemodynamic responses to orthostatic stress are not well understood.
Purpose of the Study:
- To identify age-specific hemodynamic alterations during the upright tilt test in patients with vasovagal syncope.
- To compare hemodynamic responses across different age groups.
Main Methods:
- 115 patients with unexplained syncope underwent a 65-degree upright tilt test with pharmacological challenge (sublingual nitrate).
- Noninvasive monitoring of blood pressure, heart rate, total peripheral resistance, and stroke volume was performed.
- Patients were stratified into three age groups: 10-30 years, 31-50 years, and >51 years.
Main Results:
- Older patients (Group 3) showed lower heart rate increases and earlier reductions in total peripheral resistance and systolic blood pressure during the tilt test.
- Younger patients (Group 1) exhibited more significant decreases in stroke volume.
- In the minutes preceding syncope, younger subjects had a transient heart rate increase, while older subjects experienced a progressive blood pressure drop.
Conclusions:
- Blunted sympathetic activation is observed in older patients during passive orthostatism.
- In younger individuals, syncope appears linked to an excessive sympathovagal reaction.
- In older individuals, syncope is associated with overwhelming central vagal activity and defective peripheral sympathetic activation.
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