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Updated: Aug 9, 2026

Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance
Published on: March 21, 2013
Malignant neurocardiogenic vasovagal syncope associated with chronic exaggerated vagal tone
M Nakagawa1, N Takahashi, K Yufu
1Department of Laboratory Medicine, Oita Medical University, 1-1 Idaigaoka, Hasama-machi, Oita 879-5593, Japan. mikinak@oita-med.ac.jp
Abstract:
A head-up tilt test was performed in a 23-year-old woman with a history of two syncopal episodes. The patient developed abrupt syncope with 48 seconds of sinus arrest. Analysis of the high frequency (HF) power of heart rate variability over 24 hours before and after metoprolol therapy showed a significantly elevated HF power in this patient compared to age- and sex-matched healthy subjects. It is suggested that an exaggerated resting vagal tone might be associated with the pathogenesis of prolonged asystole in our patient.
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