BACKGROUND: Transthoracic impedance measurements (TIM) is primarily used for minute ventilation rate adaptive sensors in pacemakers. With elevated impedance, the TIM electrical signal itself is oversensed, causing device malfunction. OBJECTIVE: We report an increased incidence of TIM oversensing. METHOD: Retrospective chart review. We review existing records of 18 patients who have demonstrated device malfunction with TIM oversensing. RESULTS: We have found a 1.8% incidence of TIM-related oversensing in our patient population of 959 patients with contemporary Boston Scientific (Marlborough, MA, USA) pacemakers and cardiac resynchronization therapy pacemakers. One patient experienced a syncopal episode. CONCLUSION: Oversensing with pacing inhibition is apparent with the potential of adverse effects to patients.
BACKGROUND: Transthoracic impedance measurements (TIM) is primarily used for minute ventilation rate adaptive sensors in pacemakers. With elevated impedance, the TIM electrical signal itself is oversensed, causing device malfunction. OBJECTIVE: We report an increased incidence of TIM oversensing. METHOD: Retrospective chart review. We review existing records of 18 patients who have demonstrated device malfunction with TIM oversensing. RESULTS: We have found a 1.8% incidence of TIM-related oversensing in our patient population of 959 patients with contemporary Boston Scientific (Marlborough, MA, USA) pacemakers and cardiac resynchronization therapy pacemakers. One patient experienced a syncopal episode. CONCLUSION: Oversensing with pacing inhibition is apparent with the potential of adverse effects to patients.