Use of intravenous esmolol to predict efficacy of oral beta-adrenergic blocker therapy in patients with neurocardiogenic syncope.

Abstract

The usefulness of esmolol in predicting the efficacy of treatment with an oral beta-adrenergic blocking agent was evaluated in 27 consecutive patients with neurocardiogenic syncope. Seventeen patients had a positive head-up tilt test response at baseline and 10 patients required intravenous isoproterenol for provocation of hypotension. All patients were then given a continuous esmolol infusion (500 micrograms/kg per min loading dose for 3 min followed by 300 micrograms/kg per min maintenance dose) and rechallenged with a head-up tilt test at baseline or with isoproterenol. Of the 17 patients with a positive baseline tilt test response, 11 continued to have a positive response to esmolol challenge. Sixteen patients (including all 10 patients with a positive tilt test response with isoproterenol) exhibited a negative response to upright tilt during esmolol infusion. Irrespective of their response to esmolol infusion, all patients had a follow-up tilt test with oral metoprolol after an interval of greater than or equal to 5 half-lives of the drug. All 16 patients (100%) with a negative tilt test response during esmolol infusion had a negative tilt test response with oral metoprolol. Of the 11 patients with a positive tilt test response during esmolol infusion, 10 (90%) continued to have a positive response with oral metoprolol. It is concluded that in the electrophysiology laboratory, esmolol can accurately predict the outcome of a head-up tilt response to oral metoprolol. This information may be helpful in formulating a therapeutic strategy at the initial head-up tilt test in patients with neurocardiogenic syncope.

• Authors: J S Sra, V S Murthy, M R Jazayeri, Y H Shen, P J Troup, B Avitall, M Akhtar
• Journal: Journal of the American College of Cardiology (J Am Coll Cardiol) Vol. 19 Issue 2 Pg. 402-8 (Feb 1992) ISSN: 0735-1097 [Print] United States
• PMID: 1346266 (Publication Type: Journal Article)

Chemical References

• Adrenergic beta-Antagonists
• Propanolamines
• Metoprolol
• Isoproterenol
• esmolol

Topics

• Administration, Oral
• Adrenergic beta-Antagonists
• Female
• Humans
• Hypotension, Orthostatic (complications, diagnosis, epidemiology)
• Isoproterenol
• Male
• Metoprolol (administration & dosage, therapeutic use)
• Posture
• Predictive Value of Tests
• Propanolamines
• Syncope (drug therapy, etiology)