Sympathomimetic infusion and cardiac repolarization: the normative effects of epinephrine and isoproterenol in healthy subjects.
Effects of Epinephrine and Isoproterenol on QT Interval.Introduction: Catecholamines are known to affect cardiac repolarization, and provocation with either isoproterenol or epinephrine has been proposed as a tool for uncovering latent repolarization abnormalities. This study systematically compares...
| Publicado en: | Journal of Cardiovascular Electrophysiology Vol. 17; no. 9; pp. 983 - 990 |
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| Autores principales: | , , , , |
| Formato: | research tables/charts Journal Article |
| Publicado: |
Wiley-Blackwell
Sep2006
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=106169210&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 106169210 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 10453873 GSB jtl: Journal of Cardiovascular Electrophysiology issn: 10453873 maglogo: Y pubinfo: dt: Sep2006 vid: 17 iid: 9 pid: 480 pub: Wiley-Blackwell place: Malden, Massachusetts artinfo: ui: 106169210 2009308336 10.1111/j.1540-8167.2006.00555.x NLM16879629 106169210 ppf: 983 ppct: 7 formats: fmt: @attributes: type: P tig: atl: Sympathomimetic infusion and cardiac repolarization: the normative effects of epinephrine and isoproterenol in healthy subjects. aug: au: Magnano AR Talathoti N Hallur R Bloomfield DM Garan H affil: Division of Cardiology/Clinical Cardiac Electrophysiology, Columbia University College of Physicians and Surgeons, 161 Fort Washington Avenue HIP 5-551, New York, NY 10032. arm6@columbia.edu. sug: subj: Autonomic Nervous System Epinephrine Therapeutic Use Isoproterenol Therapeutic Use Electrophysiology Funding Source Long QT Syndrome Human ab: Effects of Epinephrine and Isoproterenol on QT Interval.Introduction: Catecholamines are known to affect cardiac repolarization, and provocation with either isoproterenol or epinephrine has been proposed as a tool for uncovering latent repolarization abnormalities. This study systematically compares the effects of isoproterenol and epinephrine infusions on QT interval (QT), T waves and U waves in normal subjects.Methods and Results: Twenty-four normal subjects (29 +/- 8 years) were evaluated during graded infusions of up to 0.30 microg/kg/minute epinephrine and 5.0 microg/minute isoproterenol. Heart rates at peak doses were 81 +/- 13 bpm at 0.28 +/- 0.04 microg/kg/minute epinephrine and 104 +/- 5 bpm at 2.4microg/minute isoproterenol. The longest absolute QT increase was 4 +/- 5 msec above baseline during isoproterenol (P < 0.001) and 12 +/- 23 msec during epinephrine (P = 0.07), while the longest corrected QT interval (QTc) increase was 67 +/- 28 msec (P < 0.0001) and 79 +/- 40 msec (P < 0.0001) above baseline during isoproterenol and epinephrine, respectively (P = 0.12 for difference). There was a 2-fold increase in U-wave amplitude during each intervention (P < 0.001). The specificity of paradoxical QT prolongation (>/=30 msec at 0.05 microg/kg/minute or >/=35 msec at 0.10 microg/kg/minute epinephrine) and an increase in QTc >/=600 msec at any dose epinephrine were 100%. However, the specificity of other proposed criteria that utilized QTc measurement (>/=30 msec at 0.10 microg/kg/minute or >/=65 msec at any dose) was poor whether all leads or only lead II were assessed.Conclusion: Both epinephrine and isoproterenol are associated with QTc prolongation and amplification of the U wave in normal subjects. The specificity of proposed criteria for epinephrine provocation in diagnosis of the long-QT syndrome is variable; however, paradoxical QT prolongation at low-dose epinephrine or a QTc >/=600 msec is highly specific. pubtype: Academic Journal doctype: research tables/charts Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
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