13. Polymorphic Ventricular Tachycardia and Ventricular Fibrillation
Published Online: 1 NOV 2012
Copyright © 2013 John Wiley & Sons, Ltd.
Bennett's Cardiac Arrhythmias: Practical Notes on Interpretation and Treatment, Eighth Edition
How to Cite
Bennett, D. H. (2013) Polymorphic Ventricular Tachycardia and Ventricular Fibrillation, in Bennett's Cardiac Arrhythmias: Practical Notes on Interpretation and Treatment, Eighth Edition, John Wiley & Sons, Ltd, Oxford. doi: 10.1002/9781118432389.ch13
- Published Online: 1 NOV 2012
- Published Print: 14 JAN 2013
Print ISBN: 9780470674932
Online ISBN: 9781118432389
- Catecholaminergic polymorphic ventricular tachycardia ( CPVT );
- Hereditary long QT syndromes;
- Polymorphic ventricular tachycardia;
- 'Torsade de pointes' tachycardia;
- Ventricular fibrillation
Polymorphic ventricular tachycardia is characterised by repeated, progressive changes in the direction and amplitude of ventricular complexes so that they appear to ‘twist’ about the baseline.
‘Torsade de pointes’ tachycardia refers to polymorphic tachycardia when there is QT prolongation preceding the arrhythmia: correction of or treatment directed at the cause of QT prolongation is required, rather than antiarrhythmics. Causes of torsade de pointes include bradycardia; drugs (e.g. erythromycin and the antipsychotics) which prolong the QT interval; and the hereditary long QT syndromes. The hereditary long QT syndromes can cause syncope and sudden death: treatment is with beta-blockers and/or an implantable defibrillator.
The Brugada syndrome is a genetic disorder characterised by downsloping ST elevation in the right precordial leads, and it may cause ventricular fibrillation. Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare, genetically determined condition, in which polymorphic or bidirectional ventricular tachycardia can be induced by exercise, requiring beta-blockers and/or an implantable defibrillator.