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Updated: Jan 20, 2026
14:09
Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance
Published on: March 21, 2013
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ST-segment changes during tilt table testing for postural tachycardia syndrome: correlation with exercise stress test
Ramya Vajapey1, Erika Hutt Centeno1, Erik H Van Iterson1
1Department of Cardiovascular Medicine, Section of Cardiac Electrophysiology and Pacing, Cleveland Clinic, 9500 Euclid Avenue, J2-2, Cleveland, OH, 44195, USA.
Summary
Electrocardiogram (ECG) changes during tilt table testing (TTT) are common in patients with postural tachycardia syndrome (POTS). These ST-segment changes during TTT do not indicate underlying cardiac ischemia when further evaluated with exercise stress tests.
Area of Science:
- Cardiology
- Autonomic Nervous System Disorders
Background:
- Electrocardiogram (ECG) changes, including ST-segment and T-wave alterations, have been observed during tilt table testing (TTT).
- The clinical significance of these ECG changes, particularly concerning ischemic evaluation, remains unclear in patients with postural tachycardia syndrome (POTS).
Purpose of the Study:
- To determine the prevalence of ST-segment changes during TTT in young, healthy individuals diagnosed with POTS.
- To correlate observed ST-segment changes during TTT with findings from exercise stress testing.
Main Methods:
- Analysis of 255 patients diagnosed with POTS who underwent both TTT and exercise treadmill testing (ETT).
Main Results:
- ST-segment changes/depressions were observed in 45 patients (18%) during TTT, predominantly in young females.
- Of the 45 patients with TTT ST-segment changes, only three showed ST-segment depression on ETT, all with negative exercise stress echocardiograms (ESEs).
- Two additional patients exhibited ST-segment depression on ETT (but not TTT) and also had negative ESEs.
Conclusions:
- A significant proportion of young, healthy POTS patients experience ST-segment changes during TTT.
- These ST-segment changes observed during TTT in POTS patients are not indicative of underlying myocardial ischemia when assessed by ETT and ESE.
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