MAUDE Adverse Event Report: ZOLL Manufacturing Corporation LifeVest WCD 4000 System; Wearable Cardioverter Defibrillator

Model Number	LifeVest WCD 4000 System
Medical Device Problem Code	Key or Button Unresponsive/not Working (4063)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	09/24/2026
Type of Reportable Event	Malfunction
Event or Problem Description
A us distributor reported that a monitor's response buttons were not functioning.
Additional Manufacturer Narrative
Device evaluation of monitor has been completed.The reported problem (response buttons non-functional) was confirmed.Upon investigation, the response button was not functional.The cause for the failure was caused by the response button dome being damaged.The root cause of the damaged dome cannot be positively identified.No adverse event resulted from the damaged monitor.

• Brand Name: LifeVest WCD 4000 System
• Common Device Name: Wearable Cardioverter Defibrillator
• Manufacturer (Section D): ZOLL Manufacturing Corporation; 121 gamma drive; pittsburgh PA 15238
• Manufacturer (Section G): ZOLL Manufacturing Corporation; 121 gamma drive; pittsburgh PA 15238
• Manufacturer Contact: zoll mfg corporation ; 121 gamma drive; pittsburgh, PA 15238
• MDR Report Key: 50949043
• Report Number: 3008642652-2026-09539
• Device Sequence Number: 9534351
• Product Code: MVK
• UDI-Device Identifier: 00855778005005
• UDI-Public: (01)00855778005005(11)211008
• Combination Product (Y/N): N
• Initial Reporter State: PA
• Initial Reporter Country: US
• PMA/510(K) Number: P010030
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Distributor
• Type of Report: Initial
• Report Date (Section B): 09/30/2026

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Operator of Device: Lay User/Patient
• Device Model Number: LifeVest WCD 4000 System
• Is the Reporter a Health Professional?: No
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 09/28/2026
• Initial Report FDA Received Date: 09/30/2026
• Is the Device Labeled for Single Use? (Y/N): No
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Reuse
• Patient Sequence Number: 1
• Patient Sex: Unknown