MAUDE Adverse Event Report: LIVANOVA USA, INC. PULSE GEN MODEL 1000; GENERATOR

Model Number 1000

Device Problems Energy Output Problem (1431); Communication or Transmission Problem (2896); Computer Operating System Problem (2898)

Patient Problem Neck Pain (2433)

Event Date 06/01/2020

Event Type  malfunction  

Event Description

It was reported that the patient was seen by his physician due to painful stimulation that had started in after he woke up that day.The physician was unable to interrogate the device despite trying multiple times, performing troubleshooting steps.And utilizing two different programming systems.Clinic notes from that day indicated that the patient's painful stimulation was severe.The patient has denied any notable trauma to the area.Per the clinic notes from approximately two months prior the patient did have mild neck discomfort.X-rays of the vns were received and reviewed by the manufacturer and no anomalies were identified.The company representative attempted to interrogate the patient's generator 2 days later; however, the communication timed out no matter what she troubleshooting she did (including using new wand batteries, using three programming systems, using the tablet to wand cable, and moving outside with the patient to reduce electromagnetic interference).She was able to palpate the vns to ensure that the wand was positioned properly above the generator.She indicated that the patient was able to utilize his magnet over the generator to resolve the painful stimulation.The internal data logs from the tablets that attempted to interrogate the generator were reviewed.It was noted that the generator failed to respond to even the most basic command from the programming system.The data was reviewed from the patient's recent appointments and no anomalies in communication were noted.Impedance and voltage from previous visits were normal.The patient's generator was replaced on due to the communication failures.The generator was received by the manufacturer but analysis on the product has not been completed to date.No further relevant information has been received to date.

Event Description

Product analysis was completed on the returned generator.Upon receipt, the generator could not be communicated with.The device was hooked to an oscilloscope to monitor output.It was found that the correct output current value was being delivered and the correct amplitude, but all timing was off by a factor of 4 (frequency, pulse width, on-time/off-time) which explains why the patient was feeling painful stimulation.Pulse width was 4x as long and total on-time was also 4times as long- 136 seconds.In addition communication timing was 1/4 what was intended (2400 bps vs 9600 bps), which explains why the generator couldn't be communicated with.Based on this finding, a method to communicate with the generator was devised.After the generator was communicated with, a single bit flip in the generator for,ware was identified that lead to the timing being off by 4.When the bit flip was fixed, the generator was able to be communicated with normally and successfully completed a final electrical test.The generator was then tested in several conditions ( different temperatures , with simulated heartrate, different settings) in order to attempt to duplicate the bit flip and it was not duplicated.The generator's microcontroller was then sent to the vendor and the bit flip was unable to be duplicated and therefore, the cause of the event has not ben determined.No further relevant information has been received to date.

• Brand Name: PULSE GEN MODEL 1000
• Type of Device: GENERATOR
• Manufacturer (Section D): LIVANOVA USA, INC.; 100 cyberonics blvd; houston TX 77058
• MDR Report Key: 10197812
• MDR Text Key: 196764099
• Report Number: 1644487-2020-00860
• Device Sequence Number: 1
• Product Code: LYJ
• UDI-Device Identifier: 05425025750405
• UDI-Public: 05425025750405
• Combination Product (y/n): N
• PMA/PMN Number: P970003
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: company representative,health
• Type of Report: Initial,Followup
• Report Date: 10/16/2020

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
• Device Operator: Lay User/Patient
• Device Expiration Date: 03/25/2021
• Device Model Number: 1000
• Device Lot Number: 204855
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 06/15/2020
• Event Location: Other
• Initial Date Manufacturer Received: 06/01/2020
• Initial Date FDA Received: 06/25/2020
• Supplement Dates Manufacturer Received: 09/21/2020
• Supplement Dates FDA Received: 10/16/2020
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1
• Patient Age: 35 YR