Reply to the Editor— Inside-Out Insulation Failure of a Defibrillator Lead with Abrasion-Resistant Coating

Abstract

Our report1 correlated characteristic nonphysiological implantable cardioveter-defibrillator electrograms with a specific short circuit within the Durata lead to alert clinicians that simultaneous cyclical signals on both shock and sensing channels may indicate a cable-coil abrasion. The images of “inside-out” abrasion of cables through the silicone walls of their lumens show the root cause of this short circuit. They illustrate the underlying failure mechanism common to St Jude Medical’s silicone-body, multilumen defibrillation leads—whether or not they are surrounded by the external Optim™ copolymer tubing.