The patient was referred for vns replacement due to battery depletion.The explanted devices were returned to the manufacturer for analysis where it was found the lead had abraded openings in both the inner and outer tubing which coincided with lead coil break locations.Scanning electron microscopy was used and identified extensive pitting at some of the break locations.One break location showed evidence of a stress fracture (fatigue in appearance), with mechanical damage and no pitting.Another break was identified as being mechanically damaged, which prevented the identification of the fracture type; no pitting was observed at this locations.Based on the findings in the pa lab, there was evidence to suggest a discontinuity in the returned portions of the lead.The in-house programming history database was reviewed and it was found to contain information from the patient's date of implant through (b)(6) 2012.The last full system diagnostics were run in 2007 and showed the device was working as intended at that time.
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