It was noted that the patient experienced a device deficiency of low impedance.It was noted that the device deficiency resolved.Product analysis for the lead 304-20 sn (b)(6) was completed and approved.Abraded openings were identified in the inner and the outer silicone tubing of the returned lead resulting in portion of the lead coils being exposed and tangled.Scanning electron microscopy images of the negative coil show appearance indicating that a stress-induced fracture (due to rotational forces) has occurred at the end of the of the negative coil.Mechanical damage was noted in the vicinity of the broken strands.Also, secondary stress-fissured were identified in the vicinity of the coil break.The lead assembly has dried remnants of what appeared to have once been bodily fluids inside the inner and the outer silicone tubing.No obvious point of entrance was noted other than the identified punctured openings and the cut end of the returned lead portion.The overall appearance of the lead is consistent with patient manipulation of the implanted device, a ¿twiddler¿.Based on the appearance of the returned lead portions, it is believed that the reported short circuit condition was most likely caused by patient manipulation of the implanted device, a ¿twiddler¿.
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