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Updated: Jun 9, 2025
Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance
Published on: March 21, 2013
The relative contribution of hemodynamic parameters to blood pressure decrease in classical orthostatic hypotension
Boriana S Gagaouzova1,2, Amber van der Stam1,3, Madeleine Johansson4,5
1Department of Neurology and Clinical Neurophysiology, Leiden University Medical Centre, Leiden.
Insights
Total peripheral resistance (TPR) decrease is a primary cause of low blood pressure in classical orthostatic hypotension (cOH). Stroke volume (SV) decrease also contributes, with heart rate (HR) partially compensating in patients.
Area of Science:
- Cardiovascular Physiology
- Autonomic Nervous System Function
- Clinical Medicine
Background:
- Classical orthostatic hypotension (cOH) is characterized by a drop in blood pressure upon standing.
- Understanding the contributing factors to cOH is crucial for effective management.
Purpose of the Study:
- To determine the relative contributions of total peripheral resistance (TPR), stroke volume (SV), and heart rate (HR) to low blood pressure in cOH.
- To analyze these contributions at both group and individual levels.
Main Methods:
- Retrospective analysis of tilt test records from cOH patients and matched controls.
- Quantification of HR, SV, and TPR effects on mean arterial pressure (MAP) using the log-ratio method.
- Exploration of neurogenic versus nonneurogenic causes of cOH.
Main Results:
- Mean arterial pressure (MAP) decreased in cOH patients and increased in controls upon tilting.
- A reduced increase in TPR was the primary contributor to cOH, followed by a decrease in SV.
- TPR decrease was nearly exclusive to cOH patients, particularly those with severe symptoms.
Conclusions:
- HR, SV, and TPR all play a role in cOH, with TPR being key.
- A decrease in TPR is a hallmark of cOH and may be linked to hyperventilation.
- Further research is needed to understand the differences between neurogenic and nonneurogenic causes.
Purpose:
We studied the relative contributions of total peripheral resistance (TPR), stroke volume (SV) and heart rate (HR) to low blood pressure in classical orthostatic hypotension (cOH) on group and individual levels.
Methods:
We retrospectively analyzed tilt test records from cOH patients and age/sex-matched controls. We quantified relative effects of HR, SV and TPR on mean arterial pressure (MAP) with the log-ratio method. We studied relations of changes of HR, SV or TPR with the change of MAP across patients and variability of contributions of HR, SV and TPR to MAP. We also explored neurogenic vs. nonneurogenic causes.
Results:
MAP responded to tilt with a decrease in patients ( n = 80) and an increase in controls ( n = 80). A too small TPR-increase contributed most to cOH, followed by a too large SV-decrease; both effects were partially corrected by a larger increase of HR. Only TPR changes consistently affected MAP change in patients and controls. TPR decreased almost exclusively in patients, most in those with severe cOH. Contributions of HR, SV and TPR to MAP did not differ between probable neurogenic and nonneurogenic causes.
Conclusion:
HR, SV and TPR all contributed to cOH, with a key role for TPR; a decrease of TPR was almost unique to patients and may be due to hyperventilation. The lack of differences between neurogenic and nonneurogenic causes needs further study.
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