24. Implantable Cardioverter Defibrillators
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. (2012) Implantable Cardioverter Defibrillators, in Bennett's Cardiac Arrhythmias: Practical Notes on Interpretation and Treatment, Eighth Edition, John Wiley & Sons, Ltd, Oxford. doi: 10.1002/9781118432389.ch24
- Published Online: 1 NOV 2012
- Published Print: 14 JAN 2013
Print ISBN: 9780470674932
Online ISBN: 9781118432389
- Audible alert alarms;
- Defibrillation threshold (DFT);
- Defibrillator function;
- Defibrillator implantation;
- Implantable cardioverter defibrillators (ICD);
- Tiered therapy
The implantable cardioverter defibrillator (ICD) can automatically terminate ventricular tachycardia or fibrillation by delivering an appropriate therapy: either a train of rapid ventricular pacing stimuli or a DC shock. The device can also act as a pacemaker. Indications are considered in terms of primary and secondary prevention.
Primary prevention is for conditions associated with a high risk of death from ventricular tachycardia or fibrillation when these arrhythmias have not yet occurred, e.g. poor left ventricular function caused by myocardial infarction or by cardiomyopathy, or cardiac conditions which carry a high risk of sudden death, including the hereditary long QT syndromes and hypertrophic cardiomyopathy.
Secondary prevention is therapy for patients who have experienced cardiac arrest, syncope or shock due to a ventricular tachyarrhythmia not caused by a reversible condition or within six weeks of myocardial infarction, or who have had ventricular tachycardia and have a left ventricular ejection fraction ≤ 35%.
Possible complications include infection, inappropriate shock delivery, psychological distress, and lead and device malfunction.