MAUDE Adverse Event Report: BOSTON SCIENTIFIC CORPORATION ENDOTAK RELIANCE G; Implantable lead

Model Number	0175
Medical Device Problem Code	High impedance (1291)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	05/04/2026
Type of Reportable Event	Death
Event or Problem Description
It was reported that this right ventricular (rv) lead exhibited a gradual rise in shock impedance measurements within range.Technical services (ts) was consulted and stated there were no out of range measurements observed.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 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 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.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.A risk review was completed and confirmed that the event of shock impedance high within normal limits - increasing gradually was defined in the risk documentation.This event type has been accounted for during product risk analysis to support acceptable risk benefit for the product.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.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): CPI - Del Caribe; guidant puerto rico b. v.; #12, rd. #698; dorado PR 00646
• Manufacturer Contact: mark mischke ; 4100 hamline avenue north; saint paul, MN 55112 ; +1(612)875-7234
• MDR Report Key: 50002370
• Report Number: 2124215-2026-39797
• Device Sequence Number: 10624872
• Product Code: LWS
• UDI-Device Identifier: 00802526373732
• UDI-Public: (01)00802526373732(17)060525
• Combination Product (Y/N): Y
• Initial Reporter State: PA
• Initial Reporter Country: US
• PMA/510(K) Number: P910073
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2004
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Other Health Care Professional
• Type of Report: Initial,Followup
• Report Date (Section B): 09/04/2026

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: 05/25/2006
• Device Model Number: 0175
• Device Catalogue Number: 0175
• 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: 07/06/2026
• Supplement Date Received by Manufacturer: Not provided
• Initial Report FDA Received Date: 07/27/2026
• Supplement Report FDA Received Date: 09/04/2026
• Was Device Evaluated by Manufacturer? (Y/N): No
• Date Device Manufactured: 05/25/2004
• 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
• Outcome Attributed to Adverse Event: Death
• Patient Age: 70 YR
• Patient Sex: Male