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

Model Number WCD 4000

Device Problems False Alarm (1013); Inappropriate/Inadequate Shock/Stimulation (1574); Device Stops Intermittently (1599); Device Displays Incorrect Message (2591)

Patient Problems Loss of consciousness (2418); Electric Shock (2554)

Event Date 04/20/2018

Event Type  Injury  

Manufacturer Narrative

There was no death associated with the defibrillation event.There is no indication that the patient sustained a serious injury.Device evaluation summary: electrode belt sn (b)(4) was returned and evaluated at the distributor, in accordance with procedures recommended by zoll manufacturing corporation.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.The pulse delivery circuitry test verified proper delivery of a full energy 150j biphasic pulse.The functional testing confirmed proper ecg acquisition and pulse delivery functionality.Device evaluation of monitor sn (b)(4) has been completed.Upon investigation the monitor was not properly producing a driven ground signal.The cause for the failure was isolated to an open r781 driven ground resistor on the computer/analog board.There is no indication that the monitor malfunction caused or contributed to the inappropriate treatment as the device was still able to monitor the patient, detect an arrhythmia, and deliver a treatment shock.Additional inappropriate defibrillation narrative: the investigation into the event concludes that there was no device malfunction associated with the inappropriate treatment event.A cause and effect analysis was conducted (attached) using all of the available information which includes the incident report, device evaluation, software flag files, and ecg strips (attached).The primary cause of the inappropriate shock was improper response button use (response buttons pressed intermittently after shocks were delivered).The ecg analysis, conducted by trained ecg technicians, identified the primary cause of the false detection was rapid atrial fibrillation (af) rate at or above the treatment threshold.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.(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 iec (b)(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 eight shocks.The patient was reportedly at the hospital at the time of the event.It was reported that the patient's blood pressure was low, prompting the patient to go to the hospital.When the patient arrived at the hospital, the device started alarming and treated the patient.The patient lost consciousness while on the bed and the nurses started to perform cpr after the treatment event.The patient regained consciousness.Rapid atrial fibrillation (af) at or above the treatment threshold contributed to the false detection.The rapid rate satisfied the rate detector of the detection algorithm.The response buttons were pressed intermittently following delivery of shocks.The response buttons functioned appropriately.Following the treatment, the patient was remained hospitalized and continued wearing the device.

• 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: manuela parra ; 121 gamma drive; pittsburgh, PA 15238-3495 ; 4129683333
• MDR Report Key: 7606565
• MDR Text Key: 111224759
• Report Number: 3008642652-2018-05340
• 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: 06/14/2018

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 06/15/2018
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Device Operator: Lay User/Patient
• Device Model Number: WCD 4000
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 05/24/2018
• Was the Report Sent to FDA?: No
• Date Manufacturer Received: 05/18/2018
• Was Device Evaluated by Manufacturer?: Device Not Returned to Manufacturer
• Date Device Manufactured: 04/17/2014
• 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: 61 YR