Prevention of inappropriate ICD shocks due to lead insulation failure by continuous monitoring and automatic alert.

Patients with implantable cardioverter defibrillator lead insulation failures may present with oversensing and/or abnormal impedance. The Lead Integrity Alert (LIA) monitors right ventricular pace/sense leads using both continuous oversensing and daily impedance measurementd. Oversensing consists of isolated short R-R intervals and nonsustained runs of short R-R intervals. The LIA algorithm has been studied for Sprint Fidelis conductor fractures, but not for lead insulation failures. We report on a patient with a failed St. Jude Riata™ ST lead (St. Jude Medical, St. Paul, MN, USA) connected to a Medtronic Virtuoso DR (Medtronic Inc., Minneapolis, MN, USA) with the LIA. Oversensing triggered the LIA, while the impedance trend was normal.