MAUDE Adverse Event Report: THORATEC CORPORATION THORATEC® HEARTMATE II®, SYSTEM CONTROLLER; VENTRICULAR (ASSIST) BYPASS

Model Number	106762
Medical Device Problem Codes	Display or Visual Feedback Problem (1184); Complete Loss of Power (4015)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	11/20/2025
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
No further information was provided.A supplemental report will be submitted once the manufacturer¿s investigation is complete.
Event or Problem Description
It was reported that a patient, who uses an ungrounded cable due to a history of short to shield, had a "loss of external power" alarm while connected to the power module.The patient then switched to their batteries.When the patient was on the phone with the clinic, the clinic had the patient switch one system controller power cable to the power module and the alarm reoccurred.This was the same for both the white and black power leads.The patient presented to the clinic and was connected to the power module in the clinic but on their ungrounded cable.Log files were submitted for review and recorded unusual voltages connected to power module, the motor function was not affected by this event.It was planned to exchange the power module and replace the ungrounded patient cable.It was also noted that the system controller had a dim pump running symbol and the system controller would be exchanged.The system controller was exchanged, and log files were submitted for review which captured no unusual events.
Additional Manufacturer Narrative
Manufacturer's investigation conclusion: the reported event of the system controller¿s green pump indicator light emitting diodes (leds) being dim was confirmed via evaluation of the system controller.The reported event of the no external power alarm was confirmed via log file analysis.Review of the submitted log file revealed on (b)(6) 2025, fluctuating relative state of charge (rsoc) voltage was captured while connected to battery power.The voltage fluctuations caused brief intermittent low voltage alarms to activate.On (b)(6) 2025 a no external power alarm was active while connected to the power module.The bus voltage was noted to be 11.8 volts and the black and white rsoc voltages were 8.4 volts.This is under the voltage threshold, when connected to a power module, leading to the no external power alarm.During this time the backup battery functioned as intended and supported the system.The no external power alarm cleared once the patient connected to battery power.Of note, throughout the file it was observed that there was lower than typical voltages when connected to the power module, ranging between 13.6 and 14.6 volts.No other notable events or alarms were captured.Pump operation was not affected, and the device appeared to function as intended.The returned system controller, serial number (b)(6), was functionally tested, and its green pump indicator leds were observed to be dim.Additionally, the controller did not pass the cable continuity test due to several wires measuring outside of the expected resistance threshold.This is consistent with wire fatigue and repetitive flexing of the power cables.The returned system controller was connected to a mock loop with the returned power module, serial number (b)(6), and patient cable, serial number (b)(6).The wires of the system controller and patient cable were manipulated by hand.The no external power alarm was unable to be reproduced.Reported information stated the system controller, serial number (b)(6), was exchanged.The root cause of the no external power alarm could not be conclusively determined through this analysis; however, the observed power cable wire fatigue is consistent with causing the alarm to activate.A corrective and preventative action (capa) has been implemented to address the hmii system controller¿s green pump indicator leds becoming dim.This controller was manufactured prior to the corrective action¿s implementation.The current revision of the instructions for use (ifu) can be found on the eifu page of the abbott website.Heartmate ii instructions for use section 7-¿alarms and troubleshooting¿ and heartmate ii patient handbook section 5-¿alarms and troubleshooting¿ explain how to properly interpret and troubleshoot no external power and low voltage alarms.Heartmate ii instructions for use section 8-¿equipment storage and care¿ and heartmate ii patient handbook section 6-¿caring for the equipment¿ explain how to properly take care and maintain the integrity of the system controller.Heartmate ii instructions for use section 2 - ¿system operations¿ and heartmate ii patient handbook section 2 - ¿how your heart pump works¿ warns the user that at least one system controller power cable must be connected to a power source at all times.Heartmate ii instructions for use section 8 ¿ ¿equipment storage and care¿ and heartmate ii patient handbook section 6 ¿ ¿caring for equipment¿ explain how to properly care for the equipment, including their system controller power cables.Additionally, heartmate ii patient handbook section 10 entitled ¿safety checklists¿, instructs users to regularly inspect their accessories ¿ including their controller power cables ¿ for damage, and to replace any equipment that appears damaged or worn.The heartmate ii patient handbook section titled ¿emergency contact list¿ cautions users to call their hospital contacts if they think, for any reason, any portion of their equipment is not functioning as usual, is broken, or they are uncomfortable with the operation of the equipment.The relevant sections of the device history records were reviewed and showed no deviations from manufacturing or quality assurance specifications.No further information was provided.The manufacturer is closing the file on this event.

• Brand Name: THORATEC® HEARTMATE II®, SYSTEM CONTROLLER
• Common Device Name: VENTRICULAR (ASSIST) BYPASS
• Manufacturer (Section D): THORATEC CORPORATION; 6035 stoneridge drive; pleasanton CA 94588
• Manufacturer (Section G): THORATEC CORPORATION; 6035 stoneridge drive; pleasanton CA 94588
• Manufacturer Contact: fredric gold ; 6035 stoneridge drive; pleasanton, CA 94588 ; 7818528207
• MDR Report Key: 23682267
• Report Number: 2916596-2025-07622
• Device Sequence Number: 21248144
• Product Code: DSQ
• UDI-Device Identifier: 00813024011286
• UDI-Public: (01)00813024011286(17)211218
• Combination Product (Y/N): N
• Initial Reporter State: MI
• Initial Reporter Country: US
• PMA/510(K) Number: P060040
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Health Professional,Company Representative
• Initial Reporter Occupation: Nurse
• Type of Report: Initial,Followup
• Report Date (Section B): 02/23/2026

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: 12/18/2021
• Device Model Number: 106762
• Device Catalogue Number: 106762
• Device Lot Number: 6824617
• 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: 11/20/2025
• Supplement Date Received by Manufacturer: 02/20/2026
• Initial Report FDA Received Date: 12/01/2025
• Supplement Report FDA Received Date: 02/23/2026
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 12/19/2018
• 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: 74 YR
• Patient Sex: Male
• Patient Weight: 91 KG