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

Model Number	0185
Medical Device Problem Codes	High impedance (1291); Nonstandard Device (1420)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	08/20/2025
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that this right ventricular (rv) lead exhibited high within range shock impedances measurements around 67 ohms.The physician opted to explant and replace this lead.No additional adverse patient effects were reported.This lead has not been returned.
Additional Manufacturer Narrative
Upon receipt at our post market quality assurance laboratory, a thorough evaluation of the lead was performed.Visual inspection noted that the lead was returned severed at 130 millimeters (mm) from the terminal end, likely related to induced damage during explant.Calcification was observed on the outer insulation and shocking coils as well as insulation damage consistent with lead-on-lead abrasion.Investigation of the available information/data determined that the observed gradual rise in lvsi measurements was likely associated with calcification.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.
Event or Problem Description
It was reported that this right ventricular (rv) lead exhibited high within range shock impedances measurements around 67 ohms.The physician opted to explant and replace this lead.No additional adverse patient effects were reported.This lead has been returned.

• 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: 23009967
• Report Number: 2124215-2025-63430
• Device Sequence Number: 10516754
• Product Code: LWS
• UDI-Device Identifier: 00802526531194
• UDI-Public: (01)00802526531194(17)150917
• Combination Product (Y/N): Y
• Initial Reporter State: IN
• Initial Reporter Country: US
• PMA/510(K) Number: P910073
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2013
• Device Explanted Year: 2025
• 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): 01/15/2026

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Operator of Device: Lay User/Patient
• Device Expiration Date: 09/17/2015
• Device Model Number: 0185
• Device Catalogue Number: 0185
• Device Lot Number: 355738
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 08/20/2025
• Supplement Date Received by Manufacturer: 01/08/2026
• Initial Report FDA Received Date: 09/09/2025
• Supplement Report FDA Received Date: 01/15/2026
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 09/17/2013
• Is the Device Labeled for Single Use? (Y/N): Yes
• Usage of Device: Initial
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Required Intervention; Hospitalization
• Patient Age: 55 YR
• Patient Sex: Female