Limitations of head-up tilt test for evaluating the efficacy of therapeutic interventions in patients with vasovagal syncope: results of a controlled study of etilefrine versus placebo.

Abstract

OBJECTIVES:

This study assessed the efficacy of oral etilefrine (10 mg three times a day) in preventing a positive response to head-up tilt testing.

BACKGROUND:

Previous reports have suggested that oral etilefrine can be effective either in preventing a positive response to head-up tilt testing or in reducing syncopal recurrences in patients with vasovagal syncope. Up to now most studies assessing drug therapy in these patients have been uncontrolled.

METHODS:

This was a randomized double-blind crossover study of etilefrine versus placebo in 30 consecutive patients with syncope and a baseline positive head-up tilt test. After the first test, patients had no treatment for 3 days and were randomized to receive etilefrine or placebo for 4 additional days. They underwent tilt testing under treatment and again after 3 days of washout; they then received the alternative treatment for 4 days, and a third test was performed.

RESULTS:

Head-up tilt test results were negative in 13 (43%) patients with etilefrine and 15 (50%) with placebo (p = NS). Therefore, the statistical power of the study was only 10%. The rate of positive responses decreased with repeated testing irrespective of the assigned treatment: A positive response was obtained during the second head-up tilt test in 20 patients (10 with placebo, 10 with etilefrine) but in only 12 during the third (7 with etilefrine, 5 with placebo) (p < 0.05).

CONCLUSIONS:

Oral etilefrine (10 mg three times a day) was not superior to placebo in preventing a positive response to head-up tilt testing. Despite a low statistical power, the high rate of negative response with placebo (50%) suggests that controlled trials are needed to assess the real efficacy of any treatment in patients with vasovagal syncope.

• Authors: A Moya, G Permanyer-Miralda, J Sagrista-Sauleda, X Carne, T Rius, L Mont, J Soler-Soler
• Journal: Journal of the American College of Cardiology (J Am Coll Cardiol) Vol. 25 Issue 1 Pg. 65-9 (Jan 1995) ISSN: 0735-1097 [Print] United States
• PMID: 7798528 (Publication Type: Clinical Trial, Comparative Study, Journal Article, Randomized Controlled Trial)

Chemical References

• Placebos
• Etilefrine

Topics

• Administration, Oral
• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Chi-Square Distribution
• Cross-Over Studies
• Double-Blind Method
• Etilefrine (therapeutic use)
• Female
• Humans
• Male
• Middle Aged
• Placebos
• Syncope (diagnosis, drug therapy)
• Tilt-Table Test (statistics & numerical data)