MAUDE Adverse Event Report: BOSTON SCIENTIFIC CORPORATION ENDOTAK RELIANCE G; IMPLANTABLE LEAD

Model Number	0174
Medical Device Problem Codes	High impedance (1291); Failure to Read Input Signal (1581)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	03/08/2026
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
This product has not been returned to boston scientific and physical analysis could not be conducted.Investigation of the available information/data determined that the observed gradual rise in low-voltage shock impedance (lvsi) measurements was likely associated with calcification, as there was no conclusive evidence of compromised physical or electrical integrity of the lead.This condition may develop over time and can be reflected in a gradual and sustained increase in shock impedance measurements.Boston scientific issued a field safety notice to physicians in (b)(6) 2025 regarding the potential for reliance defibrillation leads with expanded polytetrafluoroethylene (eptfe) coating to exhibit a pattern of gradually increasing lvsi measurements due to calcification, which may result in elevated high-voltage shock impedance (hvsi) measurements and reduced shock efficacy.A review of the device history record (dhr) was performed.The review of the dhr identified that there were no process related non-conformances, scrap, or rework performed during the production that could explain the event.The reviews ensure each device meets specification prior to release for use.There is no indication the device manufacturing process contributed to the reported complaint.Review of labeling determined that the complaint situation was listed in the manual.There was no indication in the complaint that the product was not used in accordance to labeling.The manual was unlikely to be the cause of the reported complaint; translation, wording, or graphics does not require further review.
Event or Problem Description
It was reported that during a clinic visit, the health care professional (hcp) called technical services (ts) for further review of the device data due to concerns of increase in right ventricular (rv) lead shock impedances.Upon review of the daily threshold and impedance measurements trends, the rv lead exhibited out of range intrinsic amplitude measurements and a gradual rise in the shock lead impedances from about 50 ohms to 108 ohms since 2018.It was noted the shock impedance measurements were within normal limits (wnl).Ts recommended for continued monitoring.At this time, this rv lead remains in service.No adverse patient effects were reported.

• Brand Name: ENDOTAK RELIANCE G
• Common Device Name: IMPLANTABLE LEAD
• Manufacturer (Section D): BOSTON SCIENTIFIC CORPORATION; 4100 hamline avenue north; saint paul MN 55112
• Manufacturer (Section G): CPI - DEL CARIBE; guidant puerto rico b. v.; #12, rd. #698; dorado PR 00646
• Manufacturer Contact: timothy degroot ; 4100 hamline avenue north; saint paul, MN 55112 ; 6515826168
• MDR Report Key: 25089098
• Report Number: 2124215-2026-24393
• Device Sequence Number: 17394602
• Product Code: LWS
• UDI-Device Identifier: 00802526373640
• UDI-Public: (01)00802526373640(17)090829
• Combination Product (Y/N): Y
• Initial Reporter State: MI
• Initial Reporter Country: US
• PMA/510(K) Number: P910073
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2008
• 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
• Report Date (Section B): 05/05/2026

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 Expiration Date: 08/29/2009
• Device Model Number: 0174
• Device Catalogue Number: 0174
• 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: 04/20/2026
• Initial Report FDA Received Date: 05/05/2026
• Date Device Manufactured: 08/29/2007
• 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: 73 YR
• Patient Sex: Female