The Effect of Mental Stress on the Non-Dipolar Components of the T Wave: Modulation by Hypnosis
Peter Taggart, MD,
Peter Sutton, PhD,
Chris Redfern,
Velislav N. Batchvarov, MD,
Katerina Hnatkova, PhD,
Marek Malik, PhD,
Ursula James, FBSCH and
Avy Joseph, MSc
From the Department of Cardiology, The Hatter Institute and Centre for Cardiology, University College London Hospitals, London, UK (P.T., P.S., C.R.); The London College of Clinical Hypnosis (Medical), London, UK (V.NB., U.J., A.J.); Department of Cardiac and Vascular Sciences, St Georges’ Hospital Medical School, London, UK (K.H., M.M.).
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Figure 1. Flowchart of the sequence of mental stress tasks. The shaded areas indicate rest periods. The times are indicated in minutes (See text).
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Figure 2. Positive correlation between autonomic balance and changes in the nondipolar components of ventricular repolarization (T-wave residua, TWR) during emotional stress tasks: The effect of emotional stress tasks on LF/HF ratio (abscissa) and on ventricular repolarization (TWR) (ordinate) for all emotional tasks in all subjects (n = 42). Repolarization was assessed using (A) the relative T-wave residua (TWR), (B) T-wave residua to peak T (TWR-P), and (C) T-wave residua from peak T to end T (TWR-T end). A positive correlation was obtained for all three repolarization parameters, with TWR increasing with increasing LF/HF ratio.
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Figure 3. Loss of correlation between the effect of emotion on autonomic balance and on repolarization during hypnotic relaxation. The effect of emotional stress tasks on the LF/HF ratio and ventricular repolarization when the same emotional tasks were performed in the same subjects as in Figure 2 but during hypnotic relaxation. The range of autonomic changes is similar to those in Figure 2, but the effect of emotion on repolarization is markedly reduced during hypnosis, and the correlation is lost for all three measures of repolarization (A, B, and C as in Figure 2).
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Figure 4. The increases in each of the three measures of repolarization (T-wave residua (TWR), TWR-Peak T, and TWR-end T) seen in response to the emotional tasks in the nonhypnotized state were significantly reduced when the same emotional tasks were performed during hypnotic relaxation (mean ± SEM). The bars represent the mean values for increases in TWR during the stress tasks.
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Copyright © 2005 by the American Psychosomatic Society
