Abstract | BACKGROUND/OBJECTIVES:
Sodium channel blockers are used to unmask the diagnostic ECG pattern of the Brugada syndrome (BrS) in case of a non-diagnostic baseline ECG. The aim of the study was to determine clinical and ECG predictors of a positive challenge test in patients suspected to the BrS. METHODS: RESULTS: Of the 106 patients, positive tests were detected in 20 (19%) patients. During test, a transient episode of a second-degree atrioventricular block and isolated ventricular ectopies were observed in 1 (0.9%) and 2 (1.9%) patients, respectively. A QRS prolongation ≥ 30% was observed in 4 (3.8%) patients. Baseline QRS duration in V1 ≥ 110 ms had a sensitivity of 70% and a specificity of 80% for a positive response. An ST-segment elevation ≥ 0.17 mV in V2 had a sensitivity of 60% and a specificity of 82% for a positive response. Of the multiple clinical and ECG variables entered into a binary logistic regression analysis, a history of syncope (P=0.001), previous cardiac arrest (P=0.001), baseline QRS duration in V1 ≥ 110 ms (P=0.001), and baseline ST-segment elevation in V2 ≥ 0.17 mV (P=0.012) emerged as the independent predictors of a positive response to the intravenous challenge with sodium channel blockers. CONCLUSION: The results of the sodium channel blocker challenge test can be predicted by clinical presentation and baseline ECG features.
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Authors | Shahab Shahrzad, Maryam Khoramshahi, Amir Aslani, Amir Farjam Fazelifar, Majid Haghjoo |
Journal | International journal of cardiology
(Int J Cardiol)
Vol. 165
Issue 2
Pg. 285-90
(May 10 2013)
ISSN: 1874-1754 [Electronic] Netherlands |
PMID | 21917337
(Publication Type: Journal Article)
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Copyright | Copyright © 2011 Elsevier Ireland Ltd. All rights reserved. |
Chemical References |
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Topics |
- Adolescent
- Adult
- Aged
- Brugada Syndrome
(diagnosis, physiopathology)
- Electrocardiography
(drug effects, methods)
- Female
- Humans
- Infusions, Intravenous
- Male
- Middle Aged
- Retrospective Studies
- Sodium Channel Blockers
(administration & dosage)
- Treatment Outcome
- Young Adult
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