Low frequency attenuation filter as a reversible cause of inappropriate shocks due to myopotential oversensing

Inappropriate device shocks from implantable devices can be owing to supraventricular dysrhythmias, intracardiac sensing (ie, P, R, or T waves), or extracardiac detection secondary to noise from lead fracture, myopotentials, or electromagnetic interference.1 When device malfunction occurs, a rigorous exploration of programming algorithms is warranted as part of the diagnostic strategy. We present the timeline and progress of a middle-aged man who presented with recurrent inappropriate shocks owing to myopotential oversensing. This was eradicated in its entirety by simply turning “off” a specific feature that attenuates low-frequency signals, and would have prevented an unnecessary lead revision for perceived failure.