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Updated: Jul 20, 2026
05:41
Non-invasive Assessment of Microvascular and Endothelial Function
Published on: January 29, 2013
Endothelial function in young subjects with vaso-vagal syncope.
F Galetta1, F Franzoni, Y Plantinga
1Department of Internal Medicine, University of Pisa, Via Roma 67, Pisa, Italy. fgaletta@med.unipi.it
Biomedicine & Pharmacotherapy = Biomedecine & Pharmacotherapie
|August 26, 2006
Summary
Enhanced endothelial function and abnormal vasodilation contribute to vaso-vagal syncope in young individuals. This study highlights the role of increased vagal activity and peripheral vascular changes in syncope development.
Area of Science:
- Cardiology
- Vascular Biology
- Autonomic Nervous System
Background:
- Neurally mediated syncope pathogenesis is complex.
- Endothelial function and peripheral vasomotion may play a role.
Purpose of the Study:
- To investigate the role of endothelial function and peripheral vasomotion in neurally mediated syncope.
- To compare vascular and autonomic responses in syncope patients and healthy controls.
Main Methods:
- 16 patients with vaso-vagal syncope and matched controls underwent tilt testing.
- High-resolution ultrasonography measured brachial artery flow-mediated dilation (FMD) and glyceryl trinitrate (GTN) response.
- Heart rate variability (HRV) analysis was performed at rest and during tilt test.
Main Results:
- Patients with syncope exhibited significantly higher HRV parameters, indicating increased vagal activity.
- Flow-mediated dilation (FMD) was significantly greater in syncope patients compared to controls (9.2% vs. 4.6%).
- No significant difference in GTN response was observed between groups.
Conclusions:
- Augmented endothelial function and abnormal peripheral vasodilation are implicated in vaso-vagal syncope.
- Increased vagal tone and associated bradycardia contribute to syncope development in young subjects.
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