RUNAWAY PACEMAKER IN AN IMPLANTABLE CARDIOVERTER-DEFIBRILLATOR

Introduction: Runaway pacemaker is a potentially catastrophic complica tion of any permanent pacing system, Methods and Results: A 70-year-ol d man was found to have erratic behavior of his implantable cardiovert er defibrillator (ICD) during a routine outpatient interrogation. His device was turned off, and he was hospitalized in preparation for a pu lse generator replacement. During his hospitalization, his ICD unexpec tedly began pacing rapidly, Despite prompt resuscitation attempts, the patient died, Postmortem examination of the device demonstrated a cry stal oscillator failure, Conclusion: A previously unrecognized compone nt malfunction is a potentially lethal complication of ICDs.