MAUDE Adverse Event Report: ZOLL MANUFACTURING CORPORATION LIFEVEST WCD 4000 SYSTEM; WEARABLE CARDIOVERTER DEFIBRILLATOR

Model Number WCD 4000

Device Problems Defibrillation/Stimulation Problem (1573); Device Displays Incorrect Message (2591)

Patient Problem Shock (2072)

Event Date 10/09/2015

Event Type  Injury  

Manufacturer Narrative

There was no reported death and no device malfunction associated with the inappropriate defibrillation event.The monitor sn (b)(4) and belt sn (b)(4) were returned and evaluated at the distributor, in accordance with procedures recommended by zoll manufacturing corporation.The belt evaluation is still underway.The evaluation included review of downloaded software flag files (attached) on the day of the event and incoming functional testing.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.During the incoming functional testing, a 1hz simulated normal sinus rhythm signal was applied to the ecg electrodes, followed by a 5hz simulated treatable arrhythmia signal which verified proper performance of the detection algorithm.During the transition to the 5hz signal, the device was confirmed to properly enter into a treatment sequence which includes a verification of the tactile vibration alarm, audio messaging, and siren alarms, as well as a test of the pulse delivery circuitry.The pulse delivery circuitry test verified proper charging of the high voltage capacitors and proper delivery of five full energy 150j biphasic pulses.The functional testing confirmed proper response button functionality, ecg acquisition, detection algorithm performance, and pulse delivery functionality.Device manufacture date : monitor: 03/15/2013, electrode belt: 03/15/2015.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 events was lack of response button use.The ecg analysis, conducted by trained ecg technicians, identified the primary cause of the false detection as motion artifact.The following factors could not be ruled out as contributing causes of the motion artifact: body motion, poor ecg contact with skin.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.(b)(4).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 (b)(4) performance requirements for sensitivity and specificity.

Event Description

A us distributor contacted zoll on (b)(6) 2015 to report that a patient experienced a defibrillation event.Motion artifact contributed to the false detection.The patient was reported to be walking outside when the device began alarming.She reported walking inside and sitting down before being treated.The patient was conscious at the time of the event.The response buttons were not pressed during the entire event.The patient went to the er following the event and continued use of the lifevest.

• Brand Name: LIFEVEST WCD 4000 SYSTEM
• Type of Device: WEARABLE CARDIOVERTER DEFIBRILLATOR
• Manufacturer (Section D): ZOLL MANUFACTURING CORPORATION; 121 gamma drive; pittsburgh PA 15238 3495
• Manufacturer (Section G): ZOLL MANUFACTURING CORPORATION; 121 gamma drive; pittsburgh PA 15238 3495
• Manufacturer Contact: allison petzold ; 121 gamma drive; pittsburgh, PA 15238-3495 ; 4129683333
• MDR Report Key: 5220931
• MDR Text Key: 31060193
• Report Number: 3008642652-2015-07281
• Device Sequence Number: 1
• Product Code: MVK
• Combination Product (y/n): N
• PMA/PMN Number: P010030
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: distributor
• Type of Report: Initial
• Report Date: 11/09/2015

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 11/12/2015
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Lay User/Patient
• Device Model Number: WCD 4000
• Was Device Available for Evaluation?: No
• Date Manufacturer Received: 10/12/2015
• Was Device Evaluated by Manufacturer?: Device Not Returned to Manufacturer
• Date Device Manufactured: 03/15/2013
• Is the Device Single Use?: No
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Reuse
• Patient Sequence Number: 1
• Patient Outcome(s): Hospitalization; Other
• Patient Age: 68 YR