Table 2

Indications for ICD implantation16–18

“Secondary prevention”
For patients who present, in the absence of a treatable cause, with:
•  Cardiac arrest caused by either VT or VF
•  Spontaneous sustained VT causing syncope or significant haemodynamic compromise
•  Sustained VT without syncope/cardiac arrest, and who have an associated reduction in ejection fraction (< 35%) but are no worse than NYHA functional class III heart failure
“Primary prevention”
For patients with:
•  A history of previous myocardial infarction andall of the following:
 –non-sustained VT on Holter monitoring
 –inducible VT on electrophysiological testing
 –left ventricular dysfunction with an ejection fraction < 35% and no worse than NYHA functional class III heart failure
•  A familial cardiac condition with a high risk of sudden death, including:
 –long QT syndrome
 –hypertrophic cardiomyopathy
 –Brugada syndrome
 –arrhythmogenic right ventricular dysplasia
 –following repair of tetralogy of Fallot
Patient groups in whom an ICD is usually not indicated
•  Syncope of undetermined aetiology, VT/VF not inducible
•  Incessant VT
•  VT amenable to surgical or catheter ablation
•  VT/VF due to transient or reversible cause
•  Significant psychiatric illness that might be aggravated by device implant or may preclude systematic follow up
•  Terminal illness with life expectancy < 6 months
•  Patients with impaired left ventricular function undergoing coronary artery bypass graft surgery, without spontaneous or inducible VT
•  Patients with NYHA functional class IV heart failure who are not candidates for heart transplantation
  • NYHA, New York Heart Association; VF, ventricular fibrillation; VT, ventricular tachycardia.