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

Model Number	M4100
Medical Device Problem Codes	Power Problem (3010); No Apparent Adverse Event (3189)
Health Effect - Clinical Code	Unspecified Heart Problem (4454)
Date of Event	01/16/2026
Type of Reportable Event	Malfunction
Event or Problem Description
It was reported that during a routine follow-up, communication with the wise crt system could not be established despite best-practice troubleshooting.The co-implantable cardiac device was functioning normally with right ventricular pacing only.Ecg assessment following adjustment of the right ventricular pulse width showed no left ventricular pacing contribution, indicating a lack of wise system functionality.This finding was unexpected given a wise battery replacement in (b)(6) 2025.No adverse patient sequelae were reported.
Additional Manufacturer Narrative
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 that 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 unknown or unavailable.
Additional Manufacturer Narrative
The model 3100 battery and the model 4100 transmitter remain implanted in the patient, and no planned explant dates have been communicated to ebr.As the model 4100 transmitter was not returned for analysis, the root cause of the communication failure could not be determined.However, the transmitter's serial number falls within the scope of capa 20-001, which was initiated to address feedthrough failures.
Additional Manufacturer Narrative
The model 3100 battery (s/n (b)(6)) and model 4100 transmitter (s/n (b)(6)) associated with this complaint were not returned and remain implanted; therefore, no device testing, functional testing, or physical inspection could be performed and the reported failure could not be reproduced.Communication with the wise transmitter could not be established during the reported follow-up visit despite troubleshooting attempts, preventing retrieval of diagnostic interrogation data from the system.As a result, wise therapy was not delivered at that time and the patient was observed to be pacing rv-only.Available historical system log data were reviewed.The currently implanted battery (s/n (b)(6)), implanted on (b)(6) 2025, demonstrates normal early-life discharge behavior characterized by an initial voltage drop followed by stabilization within the expected voltage range.The battery voltage trend remains within the expected discharge envelope defined by the minimum and maximum model curves, indicating normal system energy consumption.Historical data from the previous battery used in this system were also reviewed and demonstrated voltage behavior consistent with expected performance.No abnormal voltage characteristics were identified that would suggest increased energy consumption, feedthrough leakage, or cable-related issues.A review of the lot history records for the battery (s/n (b)(6)) and transmitter (s/n (b)(6)) was performed.For the battery, impedance testing, leak testing, electrical testing, and sterilization documentation met all acceptance criteria.For the transmitter, acoustic testing, power consumption testing, leak testing, and sterilization documentation also met all acceptance criteria.No discrepancies or nonconformances were identified in the manufacturing records related to the reported complaint.Although kryoflex sealing was used in the transmitter build, which has been associated with certain feedthrough-related failure modes, no supporting evidence of abnormal battery behavior or power consumption was identified in the available performance data.Because the device remains implanted and telemetry communication could not be established, internal device diagnostics and hardware integrity could not be evaluated.While a system-level contributor related to the (b)(6) 2025 battery replacement procedure (such as a possible cable or feedthrough integrity compromise) cannot be excluded, available data do not indicate abnormal energy consumption or battery-related malfunction.Therefore, the specific cause of the loss of communication could not be determined.

• 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: 24194719
• Report Number: 3013596742-2026-00003
• Device Sequence Number: 18158742
• Product Code: SEG
• UDI-Device Identifier: 00859244007005
• UDI-Public: 00859244007005
• Combination Product (Y/N): N
• Initial Reporter Country: UK
• PMA/510(K) Number: P240028
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2019
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Foreign,Health Professional,Company Representative
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial,Followup,Followup
• Report Date (Section B): 03/17/2026

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: Health Professional
• Device Expiration Date: 12/02/2019
• Device Model Number: M4100
• Device Lot Number: 112018-01
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 01/16/2026
• Supplement Date Received by Manufacturer: Not provided; Not provided
• Initial Report FDA Received Date: 01/27/2026
• Supplement Report FDA Received Date: 02/20/2026; 03/17/2026
• Was Device Evaluated by Manufacturer? (Y/N): No
• Date Device Manufactured: 08/01/2018
• 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 Sex: Unknown