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Transcranial Doppler Ultrasonography during Head-Upright Tilt-Table Testing
- Carey S. Fredman, MD;
- Kurt M. Biermann, RN, BSN;
- Vipool Patel, MD;
- Erica L. Uppstrom, MD; and
- Arthur I. Auer, MD
- From St. John's Mercy Heart Center and Christian Northeast Hospital, St. Louis, Missouri. Acknowledgments: The authors thank Katheryne Dieckmann and Rebecca Nappier for technical assistance and Nancy La Chance for secretarial help in preparing the manuscript. Requests for Reprints: Carey S. Fredman, MD, FACC, Electrophysiology Laboratory and Pacemaker Services, St. John's Mercy Heart Center, 621 South New Ballas Road, #3005-B, St. Louis, MO 63141. Current Author Addresses: Dr. Fredman: Electrophysiology Laboratory and Pacemaker Services, St. John's Mercy Heart Center, 621 South New Ballas Road, #3005-B, St. Louis, MO 63141.
Head-upright tilt-table testing is often used to support the diagnosis of vasovagally mediated syncope [1-4]. Studies that have looked at the hemodynamic changes that occur during head-upright tilt-table testing [1] have shown that positive test results are often associated with both systemic hypotension and bradycardia and that hypotension almost always precedes bradycardia. In a minority of positive tilt-table tests, syncope results from hypotension alone.
Recently, a paradoxical increase in cerebrovascular resistance was shown to occur concomitantly with the development of hypotension and bradycardia in patients who had syncope during tilt-table testing [5]. We describe a previously unreported response in a patient who had near-syncope during tilt-table testing. The patient developed increased cerebrovascular resistance and showed a significant reduction in cerebral blood flow velocity in the absence of systemic hypotension or bradycardia.
Case Report
A 23-year-old white woman had had four episodes of syncope during an 11-day period. Some of the episodes were witnessed; all occurred shortly after the patient stood up from either a sitting or a supine position. The duration of unconsciousness was estimated to be 10 to 30 seconds. The patient did not injure herself. She stated that she became extremely warm and diaphoretic just before each syncopal episode and that her heart beat rapidly when she assumed the upright position. She had had no history of syncope before these recent episodes. Her only medications included birth control pills, and she had had no significant previous medical …
This 100-word excerpt has been provided in the absence of an abstract.
