MAUDE Adverse Event Report: EBR SYSTEMS, INC. WISE CRT SYSTEM; M4100

Model Number	M4100
Medical Device Problem Code	No Apparent Adverse Event (3189)
Health Effect - Clinical Code	Unspecified Heart Problem (4454)
Date of Event	09/15/2025
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
The battery (b)(6) and transmitter (b)(6) were returned to ebr for analysis.However, the investigation has not yet been completed.Ebr submits this report to comply with fda regulations 21 cfr parts 4 and 803.Ebr has made reasonable efforts to provide as much relevant information as is available to the company as of the submission date of this report.This report does not constitute an admission or a conclusion by fda, ebr, or its employees tha the device, ebr or its employee caused or contributed to the event described in the report.Any required fields that are unpopulated are blank because the information is currently known or unavailable.Ebr will submit a supplemental report if additional relevant information becomes known.
Event or Problem Description
A 77-year-old male with a wise crt system (implanted on (b)(6) 2020, solve study) underwent transmitter and battery replacement due to prior transmitter failures (2021, 2022) and loss of device interrogation since 2022.The procedure was uncomplicated, with consistent biv pacing confirmed post-op.Follow-up and wound care are ongoing.No adverse patient sequelae was reported.
Additional Manufacturer Narrative
The battery (s/n (b)(6)) and transmitter (b)(6) were returned to ebr for analysis on 03 ocobter 2025 however investigation is still ongoing.A supplemental report will be submitted upon completion of the investigation.All pertinent information available to ebr systems as of the date of this submission has been included in this report.
Additional Manufacturer Narrative
The returned transmitter (model 4100, sn (b)(6)) and battery (model 3100, sn (b)(6)) showed no gross kryoflex residue, corrosion, or delamination.External welds, wire connections, and surfaces were intact with no mechanical damage to explain the communication loss.A faint yellowish discoloration was noted near polymer interfaces, though no visible leakage was confirmed.Follow-up data from 23-nov-2022 indicated a battery voltage of approximately 2.68 v, with the voltage-based algorithm estimating 27 % energy remaining versus 59 % by the energy remaining counter (erc) a 22 % discrepancy consistent with abnormal current leakage and elevated parasitic drain.The voltage profile showed an early drop from ~3.2 v to 2.95 v, a prolonged plateau near 2.93 v, and an accelerated decline after ~day 250, characteristic of parasitic draw rather than normal discharge behavior.The abrupt communication loss and depletion pattern align with prior kryoflex-related cases involving conductive micro-paths near the feedthrough or connector interface.While no macroscopic polymer migration was evident, microscopic residues beneath encapsulated regions may have contributed to current leakage.Alternative causes such as end-of-life depletion or firmware lockup were deemed unlikely given sufficient residual capacity at the time of failure.

• Brand Name: WISE CRT SYSTEM
• Common Device Name: M4100
• Manufacturer (Section D): EBR SYSTEMS, INC.; 480 oakmead parkway; sunnyvale CA 94085
• Manufacturer (Section G): EBR SYSTEMS, INC.; 480 oakmead parkway; sunnyvale CA 94085
• Manufacturer Contact: sonia finnegan ; 480 oakmead parkway; sunnyvale, CA 94085 ; 4087201906
• MDR Report Key: 23229148
• Report Number: 3013596742-2025-00020
• Device Sequence Number: 13126315
• Product Code: SEG
• UDI-Device Identifier: 00859244007005
• UDI-Public: 00859244007005
• Combination Product (Y/N): N
• Initial Reporter Country: AS
• PMA/510(K) Number: P240028
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2021
• Device Explanted Year: 2025
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Health Professional,Company Representative
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial,Followup,Followup
• Report Date (Section B): 11/10/2025

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: Health Professional
• Device Expiration Date: 11/05/2023
• Device Model Number: M4100
• Device Lot Number: 211008-03
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 10/03/2025
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 09/15/2025
• Supplement Date Received by Manufacturer: Not provided; Not provided
• Initial Report FDA Received Date: 10/06/2025
• Supplement Report FDA Received Date: 10/23/2025; 11/10/2025
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 08/01/2021
• Is the Device Labeled for Single Use? (Y/N): Yes
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Initial
• Patient Sequence Number: 1
• Patient Age: 77 YR
• Patient Sex: Male