Electromagnetic Interference from Swimming Pool Generator Current Causing Inappropriate ICD Discharges

Figure 1

Note the high-frequency, repetitive electromagnetic (EMI) signal, exactly at 120 msec intervals. Underlying sinus rhythm and regular QRS complexes are clearly visible. The device inappropriately labeled the external AC signal as ventricular fibrillation and cardioverted with 30 J. Ab = atrial blanking period during postventricular atrial refractory period (PVARP); AP: atrial paced; AR: atrial refractory; AS: atrial sensed; CD: charge delivered; FS: (ventricular) fibrillation sensed; VP: ventricular paced; VS: ventricular sensed.