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

Model Number WCD 4000

Device Problems Over-Sensing (1438); Inappropriate/Inadequate Shock/Stimulation (1574)

Patient Problems Syncope (1610); Chest Pain (1776); Fatigue (1849); Dizziness (2194); Loss of consciousness (2418); Shock from Patient Lead(s) (3162)

Event Date 12/21/2019

Event Type  Injury  

Manufacturer Narrative

There was no death or device malfunction associated with the inappropriate defibrillation event.Device evaluation summary: electrode belt sn (b)(4) was returned to the distributor for evaluation.All gels were deployed.During the incoming functional testing, a 1hz simulated normal sinus rhythm signal was applied to the ecg electrodes.The pulse delivery circuitry test verified proper delivery of full energy 150j biphasic pulse.The functional testing confirmed proper ecg acquisition and pulse delivery functionality.There is no indication of a product malfunction.Monitor sn (b)(4) was returned to zmc from the distributor and the evaluation is currently underway.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.Device manufacture date: monitor: 04/30/2014.Electrode belt: 01/06/2014.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 lack of response button use prior to shock delivery.The response buttons were not pressed during the event.The ecg analysis, conducted by trained ecg technicians, identified the primary cause of the false detection was low amplitude oversensing and double counting.The multiple counting 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.

Event Description

A us distributor contacted zoll to report that a patient experienced an inappropriate defibrillation event consisting of one shock.The patient reportedly was getting off her couch and was feeling dizzy, tired, had chest pain, and her symptoms may have been from a syncope episode.The patient reported blacking out during the treatment and was feeling like she couldn't move anything and went unconscious.Low amplitude oversensing and double counting contributed to the false detection.The response buttons were not pressed during the event.The patient received medical attention after the event and was placed on telemetry.There was no death or device malfunction associated with the inappropriate defibrillation event.

• 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: rachel mahoney ; 121 gamma drive; pittsburgh, PA 15238-3495 ; 4129683333
• MDR Report Key: 9612514
• MDR Text Key: 188897911
• Report Number: 3008642652-2020-00514
• Device Sequence Number: 1
• Product Code: MVK
• UDI-Device Identifier: 00855778005005
• UDI-Public: 00855778005005
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: P010030
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: distributor
• Reporter Occupation: Other
• Type of Report: Initial
• Report Date: 01/20/2020

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Lay User/Patient
• Device Model Number: WCD 4000
• Device Catalogue Number: 10A0988
• Was Device Available for Evaluation?: No
• Initial Date Manufacturer Received: 12/26/2019
• Initial Date FDA Received: 01/21/2020
• Was Device Evaluated by Manufacturer?: Device Not Returned to Manufacturer
• Date Device Manufactured: 04/30/2014
• 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: 71 YR