Implantable defibrillator diagnostic storage capabilities: evolution, current status, and future utilization.

There has been a rapid and significant evolution in the stored diagnostic information available from implantable cardioverter defibrillators (ICDs). The diagnostic information available in current generation ICDs has greatly enhanced the clinicians' ability to determine the rhythm triggering device therapy as well as to identify potential problems with the ICD system. Furthermore, this information may be useful in identifying triggers of ventricular arrhythmias in patients at high risk for sudden death. The history, evolution, value, and limitations of the stored diagnostic capabilities of implantable defibrillators are discussed.