There was no death or device malfunction associated with the inappropriate defibrillation event.Device evaluation summary: electrode belt sn (b)(4) and monitor sn (b)(4) have not yet been returned from the field.Device evaluation included review of downloaded software flag files on the day of the event.The review of the software flags consisted of an analysis of the downloaded data to identify any fault flags or unusual patterns of software flags.The software flag files did not suggest a device malfunction that would contribute to the inappropriate treatment.The investigation into the event concludes that there was no device malfunction.A cause and effect analysis was conducted using all of the available information which includes the incident report, device evaluation, software flag files, and ecg strips.The primary cause of the inappropriate shock was improper response button use prior to shock delivery.The response buttons were pressed earlier in the detection sequence, but not immediately prior to shock delivery as well as after the treatment was delivered.The response buttons functioned appropriately.The ecg analysis, conducted by trained ecg technicians, identified the primary cause of the false detection was af with rvr.The rapid rate satisfied the rate detector of the detection algorithm.Inappropriate defibrillations are an anticipated risk associated with the use of the lifevest.Patients are instructed through alarms, voice messages, ifu, and training to press the response buttons to prevent an inappropriate defibrillation.The current commercial inappropriate defibrillation rate is consistent with the observed rate during the pivotal clinical trial (b)(4) (0.69% per patient-month with 90% confidence).A summary of the safety and effectiveness data (ssed), including the inappropriate defibrillation safety objective supporting fda's approval of the lifevest, can be found at http://www.Accessdata.Fda.Gov/cdrh_docs/pdf/p010030b.Pdf.The lifevest detection algorithm complies with iec 60601-2-4 performance requirements for sensitivity and specificity.
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