MAUDE Adverse Event Report: BOSTON SCIENTIFIC CORPORATION RESONATE? X4 CRT-D; cardiac resynchronization therapy defibrillator

Model Number	G447
Medical Device Problem Codes	Failure to Capture (1081); Defibrillation/Stimulation Problem (1573); Unexpected Therapeutic Results (1631); Under-Sensing (1661); High Capture Threshold (3266)
Health Effect - Clinical Code	Ventricular Fibrillation (2130)
Date of Event	07/21/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that this patient with the cardiac resynchronization therapy defibrillator (crt-d) was admitted after experiencing a ventricular tachycardia (vt)/ventricular fibrillation (vf) storm.The vf did break after the shocks, but therapy was exhausted and the arrhythmia remained.Technical services (ts) reviewed and found the device had a delay in delivering therapy due to undersensing.There was also some loss of capture (loc) noted but the patient appeared to be conducting on their own.Thresholds were noted to be high on the right ventricular (rv) lead.The patient was also noted to be on multiple life support medications.This crt-d remains in service.No additional adverse patient effects were reported.

• Brand Name: RESONATE? X4 CRT-D
• Common Device Name: cardiac resynchronization therapy defibrillator
• Manufacturer (Section D): BOSTON SCIENTIFIC CORPORATION; 4100 hamline avenue north; saint paul MN 55112
• Manufacturer (Section G): Boston Scientific Corporation; cashel road; clonmel E91 T 862; EI E91 T862
• Manufacturer Contact: timothy degroot ; 4100 hamline avenue north; saint paul, MN 55112 ; +1(651)582-6168
• MDR Report Key: 50310185
• Report Number: 2124215-2026-44488
• Device Sequence Number: 8770484
• Product Code: NIK
• UDI-Device Identifier: 00802526589539
• UDI-Public: (01)00802526589539(17)210918
• Combination Product (Y/N): N
• Initial Reporter State: TX
• Initial Reporter Country: US
• PMA/510(K) Number: P010012
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2019
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial
• Report Date (Section B): 08/18/2026

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: 09/18/2021
• Device Model Number: G447
• Device Catalogue Number: G447
• Device Lot Number: 225636
• 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: 07/22/2026
• Initial Report FDA Received Date: 08/18/2026
• Date Device Manufactured: 10/07/2019
• 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: Hospitalization; Life Threatening; Other
• Patient Age: 53 YR
• Patient Sex: Male