A Case of 25 Inappropriate Automatic Implantable Cardioverter Defibrillator Shocks and 22 Episodes of Antitachycardia Pacing.

An implantable cardioverter defibrillator (ICD) can save lives from fatal tachyarrhythmias. In rare cases, these devices can fail or malfunction. We present a case of a patient that suffered from 25 inappropriate shocks and 22 episodes of antitachycardia pacing (ATP), secondary to a probable non-traumatic dual lead fracture. One episode of ATP induced an R-on-T phenomenon, causing monomorphic ventricular tachycardia in the patient. The inappropriately functioning ICD also required two magnets to be placed on the patient's chest in the emergency department to convert the device to an asynchronous mode. An unexpected case of this magnitude and in such a brief timeframe has not been reported in prior ICD studies.