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

Model Number	0184
Medical Device Problem Code	High impedance (1291)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	10/13/2025
Type of Reportable Event	Malfunction
Event or Problem Description
It was reported that this right ventricular (rv) lead exhibited an in-range shock impedance measurement of 116 ohms.It was noted the shock impedance has been gradually rising and that calcification was suspected.Technical services (ts) recommended reprogramming the upper limit and to continue to monitor.This rv lead remains in service.No adverse patient effects were reported.
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 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 july 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.Labeling review information from pi or review of the instructions for use (ifu) confirmed there was relevant content and sufficient guidance with respect to the circumstances described within this complaint.No updates are required to the ifu as a result of this event.Based on a thorough review of the reported complaint, boston scientific has assigned an investigation conclusion code of cause traced to device design.

• 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): BOSTON SCIENTIFIC CORPORATION; road 698, lot no. 12; dorado PR 00646 -260; * 00646-2602
• Manufacturer Contact: timothy degroot ; 4100 hamline avenue north; saint paul, MN 55112 ; 6515826168
• MDR Report Key: 24545560
• Report Number: 2124215-2026-12841
• Device Sequence Number: 12193687
• Product Code: LWS
• UDI-Device Identifier: 00802526531187
• UDI-Public: (01)00802526531187(17)150613
• Combination Product (Y/N): Y
• Initial Reporter State: MA
• Initial Reporter Country: US
• PMA/510(K) Number: P910073
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2013
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Non-Healthcare Professional
• Type of Report: Initial
• Report Date (Section B): 03/09/2026

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: 06/13/2015
• Device Model Number: 0184
• Device Catalogue Number: 0184
• Device Lot Number: 325713
• Was Device Available for Evaluation?: No
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 03/04/2026
• Initial Report FDA Received Date: 03/09/2026
• Date Device Manufactured: 06/13/2013
• 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: 55 YR
• Patient Sex: Male