MAUDE Adverse Event Report: BOSTON SCIENTIFIC CORPORATION ENDOTAK RELIANCE SG; IMPLANTABLE CARDIOVERTER DEFIBRILLATORS (ICD)

Model Number	0170
Medical Device Problem Code	High impedance (1291)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	08/18/2023
Type of Reportable Event	Malfunction
Event or Problem Description
It was reported that this right ventricular (rv) lead and implantable cardioverter defibrillator (icd) exhibited shock impedance measurements of greater than 135 ohms.The device exhibited shock impedance alert a month back.Technical services (ts) recommended to increase the shock impedance alert range.This rv lead remains in service at this time.No adverse patient effects were reported.
Event or Problem Description
It was reported that this right ventricular (rv) lead and implantable cardioverter defibrillator (icd) exhibited shock impedance measurements of greater than 135 ohms.The device exhibited shock impedance alert a month back.Technical services (ts) recommended to increase the shock impedance alert range.This rv lead remains in service at this time.No adverse patient effects were reported.Additional information received indicated that there was gradual increase in pacing impedance measurements, measuring around 1400 ohms.The measurements were within the normal range.There was no noise noted and shock impedance measurements were measuring around 150 ohms.Technical services (ts) recommended reprogramming to initial and max energy shocks.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.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.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 SG
• Common Device Name: IMPLANTABLE CARDIOVERTER DEFIBRILLATORS (ICD)
• 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: 17818081
• Report Number: 2124215-2023-52663
• Device Sequence Number: 12293419
• Product Code: LWS
• UDI-Device Identifier: 00802526373282
• UDI-Public: 00802526373282
• Combination Product (Y/N): Y
• Initial Reporter State: CA
• Initial Reporter Country: US
• PMA/510(K) Number: P910073/S041
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2011
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 03/26/2026

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: 05/11/2013
• Device Model Number: 0170
• Device Catalogue Number: 0170
• Device Lot Number: 100684
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Initial
• Initial Date Received by Manufacturer: 09/18/2023
• Supplement Date Received by Manufacturer: 03/26/2026
• Initial Report FDA Received Date: 09/26/2023
• Supplement Report FDA Received Date: 03/30/2026
• Was Device Evaluated by Manufacturer? (Y/N): Device Not Returned to Manufacturer
• Date Device Manufactured: 05/11/2011
• 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: 62 YR
• Patient Sex: Female