MAUDE Adverse Event Report: ST. JUDE MEDICAL, INC.(CRM-SYLMAR) ZEPHYR XL SR; PULSE GENERATOR, PERMANENT, IMPLANTABLE

Model Number	5626
Medical Device Problem Code	Unexpected Mode Switch (4076)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	01/09/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that the patient presented for a follow-up in clinic.Upon interrogation, it was noted that the pacemaker exhibited a backup vvi mode.Programming changes were attempted but unsuccessful.The pacemaker was explanted and replaced.The patient was in stable condition.
Additional Manufacturer Narrative
The event of unexpected mode switch was confirmed.The device was received in bvvi mode with battery voltage at elective replacement indicator (eri).Analysis performed found memory errors registered in the device memory consistent with integrated circuit anomaly.The device was cut open and a new battery was connected, device product code was reloaded and no anomaly was noted.Longevity assessment was performed, and device has exceeded the total projected longevity and is considered normal battery depletion.
Additional Manufacturer Narrative
Correction: h6.Investigation findings should have been ¿4214, erroneous data transfer¿ instead of ¿114, operational problem identified¿.H6, component code should have been ¿4707, computer software¿ instead of ¿472, ic (integrated circuit) chip¿.H11.Manufacturer narrative data should have been 'the event of unexpected mode switch was confirmed.The device was received in bvvi mode with battery voltage at end of life (eol).Battery trend data derived from the device image indicated that the monthly average battery voltage remained consistently high throughout the implant duration, despite a progressive increase in measured battery impedance.The persistently elevated voltage readings are inconsistent with the impedance trend and are indicative of corrupted, uncalibrated battery voltage measurements.At the time of receipt, the device was operating in backup mode secondary to a non-maskable interrupt (nmi) event.Physical analysis, including device de-capsulation, confirmed that the in-circuit battery voltage had reached end-of-life (eol) levels.The implant duration exceeded the projected longevity based on programmed field settings, which otherwise indicated normal battery depletion behavior.Subsequent functional testing performed with a new battery installed demonstrated normal device operation.'.

• Brand Name: ZEPHYR XL SR
• Common Device Name: PULSE GENERATOR, PERMANENT, IMPLANTABLE
• Manufacturer (Section D): ST. JUDE MEDICAL, INC.(CRM-SYLMAR); 15900 valley view court; sylmar CA 91342
• Manufacturer (Section G): ST. JUDE MEDICAL, INC.(CRM-SYLMAR); 15900 valley view court; sylmar CA 91342
• Manufacturer Contact: navpreet singh ; 15900 valley view court; sylmar, CA 91342
• MDR Report Key: 24127758
• Report Number: 2017865-2026-01353
• Device Sequence Number: 10387963
• Product Code: NVZ
• UDI-Device Identifier: 05414734501712
• UDI-Public: (01)05414734501712(10)2714784(17)100331
• Combination Product (Y/N): N
• Initial Reporter Country: CA
• PMA/510(K) Number: P880086
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2009
• Device Explanted Year: 2026
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Foreign,Health Professional,User Facility,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup,Followup
• Report Date (Section B): 04/10/2026

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: Health Professional
• Device Expiration Date: 03/31/2010
• Device Model Number: 5626
• Device Lot Number: 2714784
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Is the Reporter a Health Professional?: Yes
• Was the Report Sent to FDA?: No
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 01/09/2026
• Supplement Date Received by Manufacturer: 03/17/2026; 04/09/2026
• Initial Report FDA Received Date: 01/21/2026
• Supplement Report FDA Received Date: 03/18/2026; 04/10/2026
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 09/05/2008
• 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: Required Intervention
• Patient Sex: Unknown