Catecholamine-provoked microvoltage t wave alternans in genotyped long qt syndrome.
Macrovoltage T wave alternans (TWA) has been described in congenital long QT syndrome (LQTS). Microvoltage T wave alternans (microV-TWA) at low heart rate (HR) is a marker of arrhythmogenic risk in many conditions, but its significance in LQTS has not been established. Twenty-three genotypically het...
| Publicado en: | Pacing & Clinical Electrophysiology Vol. 26; no. 8; pp. 1660 - 1668 |
|---|---|
| Autores principales: | , , , , |
| Formato: | research Journal Article |
| Publicado: |
Wiley-Blackwell
Aug2003
|
| 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=106078973&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 106078973 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 01478389 4F8 jtl: Pacing & Clinical Electrophysiology issn: 01478389 maglogo: Y pubinfo: dt: Aug2003 vid: 26 iid: 8 pid: 480 pub: Wiley-Blackwell place: Malden, Massachusetts artinfo: ui: 106078973 2009387012 10.1046/j.1460-9592.2003.t01-1-00249.x NLM12877697 106078973 ppf: 1660 ppct: 8 formats: fmt: @attributes: type: P tig: atl: Catecholamine-provoked microvoltage t wave alternans in genotyped long qt syndrome. aug: au: Nemec J Ackerman MJ Tester DJ Hejlik J Shen W sug: subj: Adrenergic beta-Agonists Pharmacodynamics Dobutamine Pharmacodynamics Long QT Syndrome Complications Long QT Syndrome Tachycardia, Ventricular Etiology Tachycardia, Ventricular Adolescence Adult Case Control Studies Electrocardiography Female Genotype Male Nonparametric Statistics Human Adolescent: 13-18 years Adult: 19-44 years Female Male ab: Macrovoltage T wave alternans (TWA) has been described in congenital long QT syndrome (LQTS). Microvoltage T wave alternans (microV-TWA) at low heart rate (HR) is a marker of arrhythmogenic risk in many conditions, but its significance in LQTS has not been established. Twenty-three genotypically heterogeneous patients with LQTS and 16 control subjects were studied at rest and during phenylephrine and dobutamine provocation. Genotyping was established by PCR amplification and DNA sequencing of the three most common LQTS genes; KCNQ1/KVLQT1 (LQT1), KCNH2/HERG (LQT2), and SCN5A (LQT3). microV-TWA was determined using Fast Fourier transform. Precluded by ectopy, microV-TWA could not be assessed in 8 of 23 patients with LQTS. In the remaining 15 patients with LQTS, microV-TWA occurred at lower HR in LQTS than in controls (117 +/- 49 vs 153 +/- 37 beats/min; P < 0.05). Patients with LQTS developed microV-TWA at HR < 150 beats/min more often than controls (10/15 vs 2/16; P = 0.003). However, microV-TWA was not detected in the 3 individuals with a history of out-of-hospital cardiac arrest including a 14-year-old male with an F339del-KVLQT1 mutation (LQT1) who had dobutamine-provoked polymorphic ventricular tachycardia requiring external defibrillation. Catecholamine-provoked microV-TWA occurs at lower HR in patients with LQTS than in healthy people but does not identify high risk subjects. pubtype: Academic Journal doctype: research Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
|---|