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Updated: Jun 8, 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
Orthostatic tolerance is difficult to predict in recurrent syncope patients
Christoph Schroeder1, Jens Tank, Karsten Heusser
1Experimental Clinical Research Center, Max-Delbrueck-Centrum for Molecular Medicine, Medical University Charité, Lindenberger Weg 80, Berlin, Germany. christoph.schroeder@charite.de
Summary
Predicting orthostatic tolerance in neurally mediated syncope patients using detailed measurements is challenging. Clinical lab findings poorly correlate with real-life syncope frequency.
Area of Science:
- Cardiology
- Neurally Mediated Syncope Research
Background:
- Previous studies indicated that orthostatic heart rate and blood pressure responses could predict tilt table responses in neurally mediated syncope patients.
- This study aimed to further investigate predictors of orthostatic tolerance.
Purpose of the Study:
- To test if detailed anthropometric and hemodynamic measurements predict orthostatic tolerance in neurally mediated syncope patients.
- To determine if orthostatic tolerance relates to real-life syncope frequency.
Main Methods:
- Analyzed data from 157 patients with recurrent syncope.
- Quantified orthostatic tolerance via head-up tilt testing with lower body negative pressure.
- Measured heart rate, blood pressure, stroke volume, heart rate and blood pressure variability, and baroreflex sensitivity.
Main Results:
- Orthostatic heart rate increase most strongly correlated with orthostatic tolerance.
- A multivariate model explained less than 40% of orthostatic tolerance variability and failed in a confirmatory cohort.
- Syncope frequency showed only a weak relationship with orthostatic tolerance.
Conclusions:
- Orthostatic tolerance in clinical settings is difficult to predict using various anthropometric and cardiovascular measurements in neurally mediated syncope patients.
- Clinical measurements showed poor correlation with actual syncope occurrence in daily life.
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