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dennis100
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« on: October 26, 2018, 01:09:19 AM »

Model Number 101
Event Date 04/15/2013
Event Type  Injury   
Manufacturer Narrative
 
Event Description
Additional information was received that the event reported was not vns related. Chest pain heart flutters. Start date of event was (b)(6) 2013. Device was off at the time related to being at or near end of battery life. The patient heart flutters were related to the patient having a low potassium level that caused a palpitation. No cardiac ischemia their chest pain resolved and was not vns related.
 
Event Description
It was reported that a vns patient reported that she was in the hospital with a heart attack 2 weeks ago. When questioned further, she reported that she just had chest pain. She stated that she has severe anxiety and her heart flutters sometimes. Good faith attempts are underway for further details about the reported event.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=3129863
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dennis100
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« Reply #1 on: October 26, 2018, 01:11:16 AM »

Model Number 104
Event Date 10/17/2012
Event Type  Injury   
Manufacturer Narrative
 
Event Description
On (b)(6) 2012, it was reported that the patient recently underwent a battery replacement on (b)(6) 2012 and the device was turned on in the operating room. Since the replacement surgery the patient was admitted to the hospital on (b)(6) 2012 due to nausea and vomiting. On (b)(6) 2012, the patient had started coughing and the mother stopped the stimulation with the magnet and took the patient to see his physician who decreased his settings and the coughing stopped. The son then started having dizziness and a blood test at that time revealed that the patient's ammonia level was high. One of the patient's seizure medications was tapered down at that point. During that time, the patient stopped eating and had decreased appetite. On (b)(6) 2012, the patient started having nausea and vomiting. The patient's mother was unsure if it occurred during stimulation or not. On (b)(6) 2012, the patient was taken to the emergency room due to the vomiting not stopping. Blood tests in the emergency room revealed that the patient's ammonia level was okay but the potassium level was low. During this time, the patient's dizziness had persisted according to the mother. The patient was sent home that same day and was still nauseated. The reporter stated that the physician believed that the patient had a distended bladder. On (b)(6) 2012, the patient was taken to the emergency room again and was given medications to help with the nausea and vomiting and was sent home. On (b)(6) 2012, the patient began experiencing severe dizziness and vomiting. The patient was taken to the hospital on (b)(6) 2012 and was admitted to the hospital. On (b)(6) 2012, the device was temporarily disabled until monday, (b)(6) 2012 to see if there is any improvement in the patient's condition. The reporter stated that the patient was still in the hospital on (b)(6) 2012 and the physicians have diagnosed the patient with a bladder disorder and don't seem to think there is an actual problem. The reporter also mentioned that the physicians have also explained that the patient has slow bowel movements which may be contributing to nausea, vomiting, and the eating disorder the patient was experiencing. It was later reported on (b)(6) 2012, the physicians haven't been able to identify the recent cause of the vomiting and other issues since the recent tests were "negative", so the patient may be readmitted to the hospital soon. The patient's settings have been decreased to half of what they were on date of implant, but it was still unclear if the issues had been resolved with this change. The patient had his device programmed off, and is still experiencing the events. On (b)(6) 2012 a physician at the hospital reported that he did not have enough information to know if the patient's events were related to vns as he is not too familiar with the patient. The patient's neurologist wondered if there could be anything leaking from the vns generator that could cause the nausea and vomiting resulting in weight loss the patient has been experiencing. The neurologist stated that she doubts that the device is leaking but that she doesn't know what is causing the patient's issues. The neurologist stated that the patient's nausea, vomiting, and dizziness are not associated with stimulation. She stated that they disabled the vns but the symptoms persisted. No causal or contributory programming or medication changes preceded the onset of the events. The patient does not have a medical history of nausea and vomiting prior to vns but does have a history of decreased appetite prior to vns.
 
Event Description
The patient's mother reported that the patient had a 51 day hospitalization for nausea and vomiting in (b)(6) 2012 that was ultimately found to be due to a reaction from two seizure medications.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=2917858
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dennis100
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« Reply #2 on: October 26, 2018, 01:12:10 AM »

Model Number 104
Device Problem Adverse Event Without Identified Device or Use Problem
Event Date 01/14/2017
Event Type  Death   
Manufacturer Narrative
Device evaluated by mfr? device evaluation is not necessary as metabolic encephalopathy is not expected to be related to the vns.
 
Event Description
The patient's last hospital discharge report was received and indicated that the patient was discharged into home hospice care three days prior to death. The patient was reportedly admitted to the hospital for metabolic encephalopathy and worsening dementia. However, the patient had other active problems reportedly, as follows: generalized convulsive epilepsy, hypothyroidism, acute kidney failure, hypernatremia, hypokalemia, osteomyelitis of jaw, weakness, debility. The hospital encounter was reportedly included consultation with palliative care. The patient was discharged in poor condition with none of his problems resolved. No further relevant information has been received to date.
 
Manufacturer Narrative

Event Description
A company representative saw through a newspaper obituary that this patient passed away in his home due to an unspecified reason. The patient's neurologist did not know the patient's cause of death as they also found out through the newspaper. No additional relevant information has been received to date.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=6335581
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dennis100
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« Reply #3 on: December 24, 2018, 06:04:55 AM »

Model Number 103
Event Date 12/12/2012
Event Type  Malfunction   
Manufacturer Narrative
New information received corrects the suspect device.

Event Description
A review of programming and diagnostic data was performed which identified a high impedance event. The high impedance was observed on (b)(6) 2012. Follow up with the nurse found that the high impedance was observed the same day the patient's generator was being replaced due to a depleted battery. The lead was not replaced. The patient was implanted with a new generator and diagnostics were all fine. Additional information from the physician found that the high impedance was initially seen as 10,000 ohms. Diagnostics two weeks after surgery showed an impedance value of 5,000 ohms, and then 10,000 ohms months later. The physician stated that before the high impedance was observed, the patient did fall. It was confirmed that the high impedance was initially observed during surgery. Ap and lateral chest and neck x-rays were taken and sent to the manufacturer for review. The generator was seen in the left chest. The filter feedthru wires were intact. The connector pin inside the connector block does not appear to be completely inserted. The lead wire was intact at the location of the connector pin. There did not appear to be any lead discontinuities or sharp bends, however there was a portion of the lead located behind the generator that could not be assessed. The electrode placement was not done as per labeling as the electrode placement is inverted. There appeared to be no propper strain relief bend or loop per labeling. There were two tie downs present, but they did not appear to be placed per labeling to secure the strain relief bend. No additional information has been provided.

Event Description
The physician reported that he may not refer the patient for replacement and may just leave the device off; however, the plan was unclear. It was later reported that the surgeon reported that he would correct the patient's lead and that the generator would be replaced also if need be. Surgery is planned, but has not occurred to date.

Manufacturer Narrative
Manufacturer reviewed x-rays of implanted device. Device manufacturing records and programming history were reviewed. Review of manufacturing records confirmed the device met all final testing specifications prior to distribution. X-rays reviewed by the manufacturer, no gross lead discontinuities visualized; however, lead pin not fully inserted past the connector block. Device failure is suspected, but did not cause or contribute to a death or serious injury.

Event Description
The patient underwent generator and lead replacement on (b)(6) 2014. It was reported that the generator was replaced prophylactically and that the high impedance was likely attributed to the lead pin not being fully inserted into the generator header. The generator and lead were returned for analysis. Analysis of the lead was completed on 05/06/2014. During the visual analysis a half set of setscrew marks was found at the end of the connector pin, indicating the connector pin had not been fully inserted into the cavity of the pulse generator at one time. The marks are evidence of a potentially insufficient mechanical contact between conductive surfaces of the generator and connector ring, resulting in a suspect electrical connection to the lead. However, based on the location of the setscrew marks on the pin, it is unknown whether a good electrical connection was present for the connector ring. During the visual analysis what appeared to be pitting was observed on the surface of the connector ring. Scanning electron microscopy was performed and identified evidence of pitting on the surface of the connector ring. Eds (energy dispersion spectroscopy - provides chemical or element identity/composition analysis) was performed on the connector ring pit deposit and identified the area as consisting of silicon, potassium, chromium, iron, nickel, sodium, manganese, fluorine and molybdenum. A definite cause for the pitting could not be determined based on the lead portion returned. However, a review of the patient x-rays' issue file correspondence suggest the electrodes may not have been attached to the nerve as intended. Other than observed pitting on the connector ring surface, no other obvious anomalies were noted except for the half set of setscrew marks found at the end of the connector pin indicating the lead had not been fully inserted into the cavity of the generator. The additional setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portion were performed, during the visual analysis, and no discontinuities were identified. There is no evidence to suggest a discontinuity in the returned portion of the device which may have contributed to the stated allegations of 'hgh impedance'. Note that since a portion of the lead assembly including the electrode array section was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead. Analysis of the generator is underway, but has not been completed to date. N.

Event Description
Analysis of the generator was completed on (b)(6) 2014. Electrical test results showed that the pulse generator performed according to functional specification. Visual inspection results revealed no external device abnormalities. There were no adverse functional, mechanical, or visual issues identified with the returned generator.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=3589007
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dennis100
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« Reply #4 on: December 29, 2018, 02:41:20 AM »

Model Number 302-20
Event Date 03/07/2013
Event Type  Malfunction   
Event Description
Follow up found that the patient went to the physician's office on (b)(6) 2013 and wanted the vns device turned back on. The physician has turned the device on to 0. 25ma and the patient is feeling some pain, especially when he turns his head to the right. The patient wants the device to remain on because he is having more seizures and is unable to get a replacement due to insurance issues. The patient also reports that he feels a pulling sensation to his neck when he turns his head to the right. The patient reports no seizures in august, but seventeen in september. The physician is aware of the manufacturer's recommendations to keep the device off, but has elected to turn it back on to a low setting.
 
Event Description
Additional programming/diagnostic history from the manufacturer's database was reviewed which confirmed the high impedance observed on (b)(6) 2013. It does not appear that the device was programmed off on this date, but there was no history following (b)(6) 2013.
 
Event Description
It was reported that the patient presented for follow up on (b)(6) 2013 at the neurologist's office and high lead impedance was observed. The patient was reporting discomfort in the neck when he turns her head to the left, when lifting things, but not during stimulation on-times. There was no specific cause for the high lead impedance, but the discomfort started about two months prior. Additionally, the patient did start working with his father about two months ago, which does include heavy lifting. There have been no drop seizures for the patient recently. The patient's father thinks that the lifting could be the cause, but the physician is not sure since he is a new patient. The device will be left on at patient's request since there are currently no adverse issues and increase in seizures. The patient is likely going for revision surgery due to the high lead impedance and believed related pain in the neck. The patient was referred for x-rays which were provided to the manufacturer for review. Ap chest and neck and lateral chest and neck x-rays dated (b)(6) 2013 were reviewed by the manufacturer. Based on the x-ray images provided, the cause of the high impedance could not be determined; however, a micro fracture or lead discontinuity in the portion of the lead that could not be assessed cannot be ruled out. Additional information received on (b)(4) 2013 indicates the physician states there is nothing obvious to be causing the pain. There are no interventions planned to date. The patient has not reported any complaints. Although surgery may occur in the future, it has not occurred to date.
 
Event Description
Analysis of the generator was completed on (b)(4) 2014. The generator performed according to functional specifications. During the product analysis there were no anomalies found with the pulse generator. Analysis of the lead was completed on (b)(4) 2014. During the visual analysis of the returned 30mm portion quadfilar coil 1 appeared to be broken approximately 1mm from the proximal end of the anchor tether. Scanning electron microscopy was performed and identified the area as being mechanically damaged with pitting which prevented identification of the coil fracture type. Pitting was observed on the coil surface. It is believed that stimulation was present for a certain period of time as evidenced by the presence of metal pitting. Low magnification sem analysis of the quadfilar coil shows characteristics typical of a lead discontinuity which may include: material fracture, rough or pitted surface, thinned material thickness, electro-etching or material dissolution. The abraded openings found on the outer silicone tubing and one inner silicone tubing and the cut ends that were made during the explanted process, most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids found inside the outer and one inner silicone tubing. What appeared to be white deposits were observed in various locations. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, sodium, magnesium, potassium, aluminum, sulphur and calcium. Refer to attached eds sheet for additional information. With the exception of the observed discontinuity the condition of the returned lead portions is consistent with conditions that typically exist following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no other discontinuities were identified. Te that since the (+) white and (-) green electrodes were not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead.
 
Event Description
It was reported that the patient was seen by the treating neurologist on (b)(6) 2013. The patient's device was disabled at the visit due to a couple of reasons. The patient was experiencing discomfort in the neck (lead site). Per the patient, he experiences a "weird feeling" when he turns to the left. The patient and caregiver were unsure about if the discomfort was associated with vns stimulation when asked. The patient's device was disabled partly as a result of this. Additionally, the patient has been experiencing an increase in seizures over the past few months that are both above and below pre-vns baseline levels. The physician was still not sure the relationship of the increased seizures to vns because at the same time as the high impedance, the patient also had multiple changes in brand name medications, was switched to generic medications and also switched physicians and had a lack of care at one point. The physician thinks there are too many factors and decided to disable the device to have a better idea of the situation. Over the last few months, the seizures have been more than the patient is used to experience prior to vns. It was planned to switch the patient back to brand name medication, but no other interventions were planned at this time. Vns magnet mode was left on for rescue purposes if necessary; however, the patient stated that it does make his neck discomfort more pronounced when he swipes it. Due to insurance reasons, the patient has not been scheduled for surgery thus far. The physician was to re-evaluate the patient the following month.
 
Event Description
Additional information was received stating that the vns patient was scheduled for surgery. The patient underwent generator and lead replacement surgery on (b)(6) 2014 due to high impedance. During surgery, the surgeon noted a suture above the electrode and dark areas on the nerve at the initial lead implant site. The patient¿s generator was replaced and the replacement generator was tested with the existing lead. Diagnostic results showed high impedance (impedance value >= 10,000 ohms). The patient¿s lead was replaced and diagnostic results showed lead impedance within normal limits for the replacement devices. The explanted generator and lead have been returned to the manufacturer where analysis is currently underway.
 
Manufacturer Narrative
Device failure occurred, but did not cause or contribute to a death.
 
Manufacturer Narrative
Manufacturer reviewed x-rays of implanted devices. Review of manufacturer device history records performed. Review of manufacturer device history records confirmed all quality tests were passed for the lead prior to distribution. X-rays reviewed by manufacturer, no gross lead discontinuities visualized. Device failure is suspected, but has not caused or contributed to a death or serious injury.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=3036493
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dennis100
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« Reply #5 on: December 29, 2018, 02:42:20 AM »

Model Number 300-20
Event Date 11/06/2013
Event Type  Malfunction   
Event Description
Analysis of the generator was completed on (b)(4) 2013. The device performed according to functional specification. Analysis of the generator in the pa lab concluded that no abnormal performance or any other type of adverse condition was found. Analysis of the lead was completed on (b)(4) 2013. Note that a portion of the lead assembly (body) including the electrodes was not returned for analysis and therefore a complete evaluation could not be performed on the entire lead product. During the visual analysis of the returned 309mm portion the unmarked connector pin quadfilar coil appeared to be broken approximately 87mm and 98mm from the connector bifurcation. Scanning electron microscopy was performed on the (-) unmarked connector pin quadfilar coil break (and identified the areas as having evidence of being worn to the point of fracture with flat spots, pitting and residual material on the coil surface. It is unknown if the breaks occurred while stimulation was present due to the absence of metal pitting on the broken coil wire surfaces. The abraded openings found on the outer and inner silicone tubes and the cut ends that were made during the explanted process most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids found inside the outer and inner silicone tubes. What appeared to be white deposits were observed in various locations. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, sodium, magnesium, potassium, iron, aluminum, sulphur and calcium. With the exception of the observed discontinuities the condition of the returned lead portions is consistent with conditions that typically exist following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pins provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no other discontinuities were identified.
 
Event Description
It was reported that the patient underwent generator and lead replacement due to high impedance. It was reported that the generator was programmed off after observing the high impedance. It is unknown if any trauma or patient manipulation occurred that could have caused or contributed to the high impedance. X-rays were not taken. The generator and lead were received by device manufacturer for analysis on 11/21/2013. Analysis is underway, but has not been completed to date. The implant card was received and indicated that the lead was replaced due to a lead break.
 
Manufacturer Narrative
Device failure occurred, but did not cause or contribute to a death or serious injury.
 
Manufacturer Narrative
Device manufacturing records were reviewed. Review of manufacturing records of the lead confirmed all quality tests were passed prior to distribution. Device failure is suspected, but did not cause or contribute to a death or serious injury.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=3497158
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« Reply #6 on: December 29, 2018, 02:43:20 AM »

Model Number 302-20
Event Date 11/06/2013
Event Type  Malfunction   
Manufacturer Narrative
Device failure occurred, but did not cause or contribute to a death.
 
Event Description
On (b)(6), 2013 it was reported that the patient underwent generator replacement that day and during surgery, high impedance was discovered. The patient was scheduled for a lead revision surgery on (b)(6) 2013. It was reported that the patient¿s generator had been prophylactically replaced on (b)(6)2013 and the lead replaced on (b)(6) 2013 due to the high impedance observed during the prophylactic generator replacement surgery. After replacement, system diagnostics showed results within normal limits. The explanted products have not been returned for product analysis to date. Generator replacement captured on mfr. Report # 1644487-2011-01493. Device manufacturing records were reviewed. Review of manufacturing records confirmed that the lead passed all functional tests prior to distribution.
 
Manufacturer Narrative
Device failure is suspected, but did not cause or contribute to a death or serious injury.
 
Event Description
Analysis of the lead was completed on (b)(4) 2014. Note that the electrodes were not returned for analysis; therefore a complete evaluation could not be performed on the entire lead product. During the visual analysis the (-) connector pin quadfilar coil appeared to be broken approximately 172mm from the end of the connector boot. Scanning electron microscopy was performed and identified the area as having evidence of being worn to the point of fracture with flat spots on the coil surface. What appeared to be pitting was observed on one of the broke coil strands. It is believed that stimulation was present for a certain period of time as evidenced by the presence of metal pitting on one of the broken coil strands. Low magnification sem analysis of the quadfilar coil shows characteristics typical of a lead discontinuity which may include: material fracture, rough or pitted surface, thinned material thickness, electro-etching or material dissolution. The abraded opening and slice marks found on the outer silicone tubing, most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids inside the outer silicone tubing. The abraded opening found on the (-) connector pin inner silicone tubing most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids inside the inner silicone tubing. There was no obvious path found for the fluid ingress observed inside the (+) connector ring inner silicone tubing. What appeared to be white deposits were observed on one of the inner silicone tubes. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, potassium, sulphur and calcium. With the exception of the observed discontinuity, the condition of the returned lead portion is consistent with conditions that typically exist following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portion were performed, during the visual analysis, and no other discontinuities were identified.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=3494941
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« Reply #7 on: December 29, 2018, 02:44:21 AM »

Model Number 302-20
Event Date 02/27/2013
Event Type  Malfunction   
Event Description
The patient had their lead replaced on (b)(6) 2013 and their explanted product has been returned for analysis. Analysis completion is pending.
 
Manufacturer Narrative
Analysis of programming history. Device manufacturing records were reviewed. Review of manufacturing records confirmed that the lead passed all functional prior to distribution. Device failure is suspected but did not cause or contribute to a death or serious injury.
 
Event Description
Notes from the patient's (b)(6) 2013 surgery were received on (b)(4) 2013. The device was reportedly not functioning for several years. (this was clarified to mean the device was at end of service). In surgery, the generator was disconnected and a new unit was connected to the existing lead. Testing showed impedance: the device was rechecked and retested. Inspection of the lead showed a longitudinal linear separation in the plastic around the metallic wires. While the wires themselves were grossly intact and there was no side of disconnect or fracture, the sheath around the wires appeared to have been worn down and split in a linear distribution. The plastic itself appeared to have eroded away from the wires. The lead was not replaced at this time. The generator was sewn into place. Lead revision is still likely but has not taken place.
 
Event Description
The lead analysis was completed on (b)(4) 2013. Analysis of the lead showed that the electrodes were not returned for analysis; therefore a complete evaluation could not be performed on the entire lead product. Visual analysis of the returned 309 mm portion showed abraded openings on the outer and inner silicone tubing in some areas. Visual analysis found that the quadfilar coil one appeared to be burnt in half in the body area of the returned lead portion. Scanning electron microscopy was performed and identified the burnt area as having the appearance of being melted, with re-solidified material (evidence of being melted at one time). Based on the obvious signs of mechanical damage on the coil surfaces, it is possible the thermally-damaged coils were exposed to a high temperature device such as a cauterizing tool (electrosurgical unit) during the explant of this lead. During the visual analysis of the returned 309 mm portion quadfilar coil two appeared to be broken approximately 211 mm from the end of the cut outer / inner silicone tubes. Scanning electron microscopy was performed and identified the area as having extensive pitting which prevented identification of the coil fracture type and mechanical damage. During the visual analysis of the returned 309 mm portion quadfilar coil two appeared to be broken approximately 250 mm from the end of the cut outer / inner silicone tubes. Scanning electron microscopy was performed and identified the area as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage, residual material and no pitting. Pitting was observed on the coil surface. It is believed that stimulation was present for a certain period of time as evidenced by the presence of metal pitting. Low magnification sem analysis of the quadfilar coil shows characteristics typical of a lead discontinuity which may include: material fracture, rough or pitted surface, thinned material thickness, electro-etching or material dissolution. The abraded openings found on the outer and inner silicone tubing two and the torn ends observed on both of the inner silicone tubes, most likely provided the leakage path for what appeared to be remnants of dried body fluids found inside the outer and inner silicone tubes. What appeared to be white deposits were observed on the connector boot. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, potassium, sulphur and calcium. With the exception of the observed discontinuity, the condition of the returned lead portions is consistent with conditions that typically exist following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no other discontinuities were identified.
 
Event Description
On (b)(6) /2013, it was reported that high impedance was seen during generator revision due to end of service. The surgeon performed a generator diagnostic on the newly implanted generator. The generator was then reconnected to the lead ensuring that the pin was past the connector block and fully inserted. Diagnostics again showed high impedance. The surgeon inspected the portion of the lead that was able to be visualized, and a break was seen with fluid in the tubing. The lead was not replaced at this time. No patient manipulation or trauma was suspected, no x-rays were taken, and the explanted generator was discarded. The new generator was not programmed on. The last known diagnostics indicated a system diagnostic with dcdc=2 approximately two years prior. The patient was lost to follow-up; however, the patient had been experiencing an increase in seizures six months prior (below baseline), and the resident generator could not be interrogated or programmed because it was at end of service. The patient could not feel normal mode or magnet mode stimulation. The patient's physician believed the increase was due to loss of therapy. A blc at this time indicated negative results. Lead revision is likely but has not taken place.

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« Reply #8 on: December 31, 2018, 09:19:17 AM »

Event Date 09/01/2010
Event Type  Injury   
Event Description
It was initially reported by the nurse that the pt was having some cardiac issues. He was fine for a couple of months after implant, but then began experiencing tachycardia. She says that one point his heart rate was 138 bpm. She believes that the device is functioning normally but says that the potassium level is at 3. 2 which is really low. Good faith attempts to obtain additional info has been unsuccessful till date.

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« Reply #9 on: January 01, 2019, 04:03:03 AM »

Model Number 300-20
Event Date 04/04/2013
Event Type  Malfunction   
Event Description
It was initially reported that the patient had high impedance on system diagnostics (dcdc = 7). However the nurse reported when normal mode diagnostics the dcdc converted was 2. The generator was recently checked (b)(6) 2012 and impedance was fine with a dcdc converter of 3 but it was unknown which diagnostic mode was run. The patient has not had any recent adverse events and there has not been any recent patient manipulation or trauma. The patient does have drop seizures and these may have caused damage to the device as the patient violently falls during those seizures. The nurse brought the patient back for another appointment to have her generator turned off. The patient was sent for x-rays and the x-rays were provided to the manufacturer for review. Based on the x-ray received there was nothing seen that would indicate there was any damage to the generator or lead; however, the presence of a micro-fracture in the lead cannot be ruled out. The patient will likely have surgery but it has not occurred to date. Review of manufacturing records confirmed there were no unresolved non conformances found with the generator and lead prior to distribution.
 
Manufacturer Narrative
Only a portion of the lead was returned for analysis which did not reveal any anomalies. Device failure is suspected in the lead portion not returned, but did not cause or contribute to a death or serious injury.
 
Event Description
Additional information was received that product analysis was completed on the generator and lead. The reported end of service allegation was duplicated in the pa laboratory and determined to be the result of normal expected battery depletion, based on the battery life analysis and electrical test results. The pulse generator module performed according to functional specifications. There were no performance or any other type of adverse conditions found with the pulse generator. Note that the lead assembly (body) including the electrodes was not returned for analysis; therefore a complete evaluation could not be performed on the entire lead product. What appeared to be white deposits were observed in various locations. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, potassium, sulphur and calcium. The condition of the returned lead portions is consistent with conditions that typically exist following an explant procedure. No obvious anomalies were noted. The setscrew marks found on the lead connector pins provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no discontinuities were identified. Based on the findings in the product analysis lab, there is no evidence to suggest a discontinuity in the returned portions of the device which may have contributed to the stated allegations¿. Note that since the lead assembly (body) including the electrode array section was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead.
 
Event Description
Additional information was received that the patient had a generator and lead replacement. The generator and lead were returned to the manufacturer for evaluation. Product analysis is planned but has not been completed.

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« Reply #10 on: January 02, 2019, 01:36:26 AM »

Model Number 302
Event Date 06/20/2013
Event Type  Malfunction   
Event Description
On (b)(6) 2013 it was reported that the vns patient¿s device had a lead fracture. A battery life calculation was performed with the available data. The result revealed 0. 0 years remaining until end of service = yes. The manufacturing records for the generator and lead were reviewed and device met all specifications prior to distribution. It was later reported that the lead fracture was identified on (b)(6) 2013 by x-ray. The patient was previously seen in 2012 and no lead impedance issues were noted. No patient manipulation or trauma occurred that is believed to have caused or contributed to the lead fracture. Lead and generator were replaced on (b)(6) 2013. Attempts for return of the explanted devices are in progress.
 
Event Description
Generator and lead were received for analysis on (b)(4) 2013. Analysis of the generator was completed on (b)(4) 2013. The module performed according to functional specifications. There was no condition noted during the product analysis evaluation that would suggest any anomaly with the device. Analysis of the lead is underway, but has not been completed to date.
 
Manufacturer Narrative
Device failure is suspected, but did not contribute to a death or serious injury.
 
Event Description
An analysis was performed on the returned lead portions and the reported high impedance and lead fracture were confirmed. Note that the electrodes were not returned for analysis and therefore a complete evaluation could not be performed on the entire lead product. During the visual analysis of the returned 335mm portion the (-) connector pin and (+) connector ring quadfilar coils appeared to be broken. Scanning electron microscopy was performed on the (+) connector ring quadfilar coil break (found at 270mm) and identified the area on one of the broken quadfilar coil strands as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage and pitting on the coil surface. The area on another broken coil strand was identified as being mechanically damaged which prevented identification of the coil fracture type with pitting. Scanning electron microscopy was performed on the (-) connector pin quadfilar coil break (found at 284mm) and identified the area as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage, fine pitting and evidence of a stress induced fracture (torsional appearance) which most likely completed the fracture. Pitting was observed on the coil surface. It is believed that stimulation was present for a certain period of time as evidenced by the presence of metal pitting. Low magnification sem analysis of the quadfilar coil shows characteristics typical of a lead discontinuity which may include: material fracture, rough or pitted surface, thinned material thickness, electro-etching or material dissolution. The abraded openings and slice marks found on the outer and inner silicone tubes and the cut ends that were made during the explanted process, most likely provided the leakage path for the remnants of what appeared to have once been body fluids inside the outer and inner silicone tubes. What appeared to be white deposits were observed in various locations. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, sodium, magnesium, potassium, zirconium, sulphur and calcium. Refer to attached eds sheet for additional information. With the exception of the observed discontinuity, the condition of the returned lead portions is consistent with conditions that typically exist following an explant procedure. No other obvious anomalies were noted except for the set of setscrew marks found near the end of the connector pin indicating the lead had not been fully inserted into the cavity of the generator. The marks are evidence of a potentially insufficient mechanical contact between conductive surfaces of the generator and connector ring, resulting in a suspect electrical connection to the lead. However, based on the location of the setscrew marks on the pin, it is unknown whether a good electrical connection was present for the connector ring. Canted spring marks were not observed on the rear end of the small o-ring. Continuity checks of the returned lead portions were performed, during the visual analysis, and no other discontinuities were identified. Based on the findings in the product analysis lab, there is evidence to suggest discontinuities in the returned portions of the device. Note that since the electrode array section was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead.
 
Manufacturer Narrative
Device failure occurred, but did not cause or contribute to a death or serious injury.

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« Reply #11 on: January 02, 2019, 01:37:19 AM »

Model Number 302-20
Event Date 05/01/2013
Event Type  Malfunction   
Manufacturer Narrative
Device failure occurred, but did not cause or contribute to a death or serious injury.
 
Event Description
On (b)(6) 2013 it was reported that the patient has high impedance and x-rays were performed that showed a clear lead break. The x-rays were not sent to the manufacturer for review. The patient underwent revision surgery that day. It was later reported that the high impedance was first observed in (b)(6) 2013. The patient¿s device was not programmed off despite the high impedance. No patient manipulation or trauma occurred that is believed to have caused or contributed to the high impedance. The explanted lead and generator were returned to the manufacturer on (b)(4) 2013 for product analysis. Product analysis is underway and has not yet been completed.
 
Manufacturer Narrative
Device failure is suspected, but did not cause or contribute to a death or serious injury.
 
Event Description
An analysis was performed on the returned lead portion. Note that a portion of the lead assembly (body) including the electrodes was not returned for analysis and therefore a complete evaluation could not be performed on the entire lead product. During the visual analysis the (+) connector ring quadfilar coil appeared to be broken approximately 252 mm from the end of the connector boot. Scanning electron microscopy was performed and identified the area as having extensive pitting which prevented identification of the coil fracture type. During the visual analysis the end of the (+) connector ring quadfilar coil appeared to be broken approximately 29 mm past the end of the abraded open / cut outer silicone tubing. The (-) connector pin quadfilar coil extended approximately 192 mm past the end of the abraded open / cut outer silicone tubing and determination could not be made as to whether the end of the coil was pulled and cut. Scanning electron microscopy was performed on the (+) connector ring quadfilar coil break (found at 29 mm) and identified the area as having extensive pitting which prevented identification of the coil fracture type. Scanning electron microscopy was performed on the (-) connector pin quadfilar coil (found at 192 mm) and identified the area on two of the coil strands as having evidence of a stress induced fracture with mechanical damage and no pitting. Determination could not conclusively be made on the fracture mechanism on these two coil strands. The area on a third coil strand was identified as having evidence of a stress induced fracture (tension overload). The fourth quadfilar coil strand was identified as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage, no pitting and evidence of a stress induced fracture (torsional appearance) which most likely completed the fracture. It is believed that stimulation was present for a certain period of time as evidenced by the presence of metal pitting. Low magnification sem analysis of the quadfilar coil shows characteristics typical of a lead discontinuity which may include: material fracture, rough or pitted surface, thinned material thickness, electro-etching or material dissolution. The abraded openings found on the outer silicone tubing, most likely provided the leakage path for what appeared to be remnants of dried body fluids found inside the outer silicone tubing. For the observed inner tubing fluid remnants, there was no obvious path for fluid ingress other than the cut ends that were made during the explanted process and the abraded opening observed on the connector ring inner silicone tubing. What appeared to be white deposits were observed on the connector boot. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, potassium and sulphur. Refer to attached eds sheet for additional information. With the exception of the observed discontinuities, the condition of the returned lead portion is consistent with conditions that typically exist following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portion were performed, during the visual analysis, and no other discontinuities were identified. Based on the findings in the product analysis lab, there is evidence to suggest discontinuities in the returned portion of the device. The pulse generator was explanted and returned for product analysis due to prophylactic replacement. The pulse generator diagnostics were as expected for the programmed parameters. A comprehensive automated electrical evaluation showed that the pulse generator performed according to functional specifications. The battery, 2. 942 volts as measured during completion of test parameter 7. 16. 10. 2 (measured diagvbat) of the final electrical test, shows a-non ifi condition. The data in the diagaccumconsumed memory locations revealed that 21. 081% of the battery had been consumed. There were no performance or any other type of adverse conditions found with the pulse generator.
 
Event Description
Review of manufacturing records confirmed sterilization for lead prior to distribution. No nonconformances were observed.

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« Reply #12 on: January 02, 2019, 01:38:04 AM »

Model Number 300-20
Event Date 09/01/2013
Event Type  Malfunction   
Event Description
The physician reported that the patient may have an issue with the device, but no additional details were provided. It was later reported that the patient will be referred to surgeon for possible revision because the device showed high impedance and end of service. The patient underwent generator and lead replacement on (b)(6) 2013. The lead and generator were returned to manufacturer for analysis. An implant card was received indicating that the patient underwent lead and generator replacement due to "lead discontinuity". Analysis of the generator was completed on (b)(6) 2013. Electrical test results showed that the pulse generator performed according to functional specifications. There were no adverse functional, mechanical, or visual issues identified with the returned generator. Analysis of the lead was completed on (b)(6) 2013. Note that a portion of the lead assembly was not returned for analysis and therefore a complete evaluation could not be performed on the entire lead product. During the visual analysis of the returned 344 mm portion the (+) marked connector quadfilar coil appeared to be broken approximately 2 mm and 3 mm from the connector bifurcation. Scanning electron microscopy was performed on the (+) marked connector quadfilar coil break (found at 2 mm) and identified the area as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage, residual material and no pitting. Scanning electron microscopy was performed on the (+) marked connector quadfilar coil break (found at 3 mm) and identified the area as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage and fine pitting. It is believed that stimulation was present for a certain period of time as evidenced by the presence of metal pitting. Low magnification sem analysis of the quadfilar coil shows characteristics typical of a lead discontinuity which may include: material fracture, rough or pitted surface, thinned material thickness, electro-etching or material dissolution. The abraded openings found on the outer and (-) unmarked inner silicone tubing and the cut ends that were made during the explanted process, most likely provided the leakage path for the remnants of what appeared to have once been body fluids found inside the outer and (-) unmarked inner silicone tubing. For the observed (+) marked connector pin inner tubing remnants of what appeared to have once been body fluids found inside, there was no obvious path for fluid ingress other than the cut ends that were made during the explanted process. What appeared to be white deposits were observed in various locations. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, sodium, magnesium, potassium, zirconium, sulphur and calcium. Refer to attached eds sheet for additional information. The slice and puncture marks observed on the inner silicone tubes (past the electrode bifurcation) appeared to have been made by a sharp object which could have occurred during the explant procedure, however this cannot be confirmed. With the exception of the observed discontinuities, the condition of the returned lead portions is consistent with conditions that typically exist following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pins provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no other discontinuities were identified.
 
Manufacturer Narrative
Device failure occurre, but did not cause or contribute to a death or serious injury.

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« Reply #13 on: January 07, 2019, 01:27:12 AM »

Model Number 302-20
Event Date 10/26/2013
Event Type  Malfunction   
Event Description
The data dump for the generator identified that the lead impedance changed from 2935 ohms to 13129 ohms on (b)(6) 2013. Analysis of the lead was completed on (b)(4) 2014. Note that the electrodes were not returned for analysis; therefore a complete evaluation could not be performed on the entire lead product. During the visual analysis what appeared to be pitting was observed on the connector pin surface. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed on the connector pin pit deposit and identified the area as consisting of chromium, iron, nickel, silicon, fluorine, sodium, potassium, aluminum and molybdenum. Another eds procedure was performed on the clean surface of the connector pin and identified the area as consisting of chromium, iron, nickel, silicone and molybdenum. A definite cause for the pitting could not be determined based on the lead portion returned. The slice mark and abraded opening found on the outer silicone tubing, most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids inside the outer silicone tubing. The condition of the returned lead portion is consistent with that which typically exists following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no discontinuities were identified. The generator analysis will be reported in mfr. Report #1644487-2014-00731.
 
Event Description
It was reported that device diagnostics resulted in high impedance. It was reported that the patient will be referred to surgeon for revision surgery. No known trauma or patient manipulation occurred that is believed to have caused or contributed to the high impedance. It is unknown if x-rays were performed. Surgery is likely, but has not occurred to date. Attempts to obtain additional information have been unsuccessful to date.
 
Manufacturer Narrative
Device manufacturing records were reviewed. Review of manufacturing records of the lead confirmed all quality tests were passed prior to distribution. Device failure is suspected, but did not cause or contribute to a death or serious injury.
 
Event Description
Additional information was received stating that the vns patient¿s device was explanted on (b)(6) 2014. The explanted generator and lead have been returned to the manufacturer where analysis is currently underway.

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« Reply #14 on: January 11, 2019, 01:31:12 AM »

Model Number 302-20
Event Date 03/26/2014
Event Type  Malfunction   
Manufacturer Narrative
Review of the available programming and diagnostic history. Describe event or problem, corrected data: the initial manufacturer report inadvertently did not include the review of the available programming and diagnostic history. Relevant tests/laboratory data, including dates, corrected data: the initial manufacturer report inadvertently did not include the review of the available programming and diagnostic history. Evaluation codes, including dates, corrected data: the initial manufacturer report inadvertently did not include the review of the available programming and diagnostic history.
 
Event Description
Review of the available programming and diagnostic history showed normal diagnostic results through (b)(6) 2011.
 
Event Description
It was reported that during generator replacement for end of service, high impedance (9225 ohms) was seen when the new generator was attached to the existing lead. It was reported that interrogation of the device prior to surgery was unsuccessful and the high impedance was not observed until the new generator was attached. The surgeon went to explant the lead and observed that the tubing was "stripped back and exposed down to the wire". The surgeon was unclear if any trauma caused the damage. It was reported that the patient was recently mugged which resulted in bruising; however, it is unknown if this may have caused or contributed to the high impedance. The lead was explanted (leaving electrodes) and a new lead was placed. Diagnostics with the new generator attached to the new lead were within normal limits (1556 ohms). The generator and lead were returned for analysis. Analysis of the lead was completed on (b)(4) 2014. Note that the (+) white and (-) green electrodes were not returned for analysis; therefore a complete evaluation could not be performed on the entire lead product. During the visual analysis abraded openings were observed on the outer silicone tubing. During the visual analysis of the returned 292mm portion the (-) connector pin quadfilar coil appeared to be broken approximately 282mm from the end of the connector boot. Scanning electron microscopy was performed and identified the area on two of the broken coil strands as being mechanically damaged which prevented identification of the coil fracture type, no pitting and residual material. The two remaining broken coil strands were identified as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage and no pitting. One of the broken coil strands was identified as having evidence of a stress induced fracture (torsional appearance) which most likely completed the fracture. During the visual analysis of the returned 146mm portion the end of the (-) green electrode quadfilar coil appeared to be broken approximately 31mm from the end of the abraded open / cut outer silicone tubing. Scanning electron microscopy was performed and identified the area as being mechanically damaged which prevented identification of the coil fracture type and no pitting. Determination could not conclusively be made on the fracture mechanism. It is unknown if the breaks occurred while stimulation was present due to the absence of metal pitting on the broken coil wire surfaces. For the observed inner tubing fluid remnants, there was no obvious path for fluid ingress other than the cut ends that were made during the explanted process. The abraded openings found on the outer silicone tubing, most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids inside the outer silicone tubing. What appeared to be white deposits were observed in various locations. Eds (energy dispersion spectroscopy ¿ provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, sodium, magnesium, potassium, aluminum, sulphur and calcium. With the exception of the observed discontinuities and abraded openings, the condition of the returned lead portions is consistent with conditions that typically exist following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no other discontinuities were identified. Analysis of the generator was completed on (b)(4) 2014. The pulse generator module performed according to functional specifications. There was no condition noted during the product analysis evaluation that would suggest any anomaly with the device.
 
Manufacturer Narrative
Failure occurred, but did not cause or contribute to a death or serious injury.

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« Reply #15 on: January 23, 2019, 01:09:07 AM »

Model Number 300-20
Event Date 06/02/2014
Event Type  Malfunction   
Event Description
Additional information was received that the generator and lead were returned to the manufacturer for evaluation. Product analysis was completed on the generator but has not been completed on the lead. In the pa lab, the device output signal was monitored for more than 24-hrs, while the generator was placed in a simulated body temperature environment. Results showed no signs of variation in the pulse generator¿s output signal and demonstrated that the device provided the expected level of output current for the entire monitoring period. The pulse generator diagnostics were as expected for the programmed parameters. In addition, a comprehensive automated electrical evaluation showed that the pulse generator performed according to functional specifications. The battery, 2. 945 volts, shows a non-ifi condition. The data in the diagaccumconsumed memory locations revealed that 14. 910% of the battery had been consumed. There were no performance or any other type of adverse conditions found with the pulse generator.
 
Manufacturer Narrative
Device failure is suspected, but did not cause or contribute to a death or serious injury.
 
Manufacturer Narrative
Device failure is suspected, but did not cause or contribute to a death or serious injury.
 
Event Description
Additional information was received that product analysis was completed on the lead. Note that a portion of the lead assembly including the electrodes was not returned for analysis and therefore a complete evaluation could not be performed on the entire lead product. The abraded opening found on the outer silicone tubing and the cut ends that were made during the explanted process, most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids found inside the outer silicone tubing. The slice mark found on the (-) unmarked connector inner silicone tubing and the cut ends that were made during the explanted process, most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids found inside the inner silicone tubing. What appeared to be white deposits were observed in various locations. Eds (energy dispersion spectroscopy - provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, sodium, magnesium, potassium, sulphur, chlorine and calcium. Refer to eds sheet for additional information. The condition of the returned lead portions is consistent with conditions that typically exist following an explant procedure. No obvious anomalies were noted. The setscrew marks found on the lead connector pins provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no discontinuities were identified. Based on the findings in the product analysis lab, there is no evidence to suggest discontinuities in the returned portion of the device which may have contributed to high impedance. Note that since a portion of the lead assembly including the electrode array section was not returned for analysis, an evaluation and resulting commentary cannot be made on that portion of the lead.
 
Event Description
It was reported that device diagnostics resulted in high impedance (> 10,000 ohms). It was reported that the patient was reporting an increase in seizures. It was noted that the patient suffers from drop attacks which are believed to be due to the high impedance. It was reported that the drop attacks are normally controlled with vns. There was no recent trauma and the patient did not manipulate the device through the skin. The patient underwent generator and lead replacement. The explanted devices are expected to be returned for analysis, but have not been received to date.

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« Reply #16 on: January 27, 2019, 04:45:02 AM »

Model Number 302-20
Event Date 09/16/2012
Event Type  Malfunction   
Manufacturer Narrative
(b)(4).
 
Event Description
An evaluation of data obtained from the generators memory revealed that a >25% change in system impedance was estimated to have occurred on (b)(6) 2012 (3235 ohms to 12832 ohms) signifying the start of the high impedance event. A high impedance warning message was first received during a follow up visit on (b)(6) 2012 during an interrogation of the patient¿s generator.
 
Manufacturer Narrative
Device failure is suspected but did not cause or contribute to a death or serious injury.
 
Manufacturer Narrative

Manufacturer Narrative
Date of event, corrected data: the initial report indicated the event occured in (b)(6) 2013 however, a review of the generator data suggests that the high impedance was first detected on (b)(6) 2012. The information has been corrected in this report.
 
Event Description
On (b)(6) 2013, it was reported that high impedance was seen regarding this patient¿s device. Follow-up showed that the high impedance was first noted in (b)(6) 2013 at which time the device was disabled. The patient was inconsistent with follow-up. At the last visit, many months prior, diagnostics were within normal limits. Clinic notes dated (b)(6) 2013 were provided. The patient was seen after a long hiatus, and the mother reported that the patient was having more seizures. The patient was seen by a different facility two months prior and was taken off of vimpat. Monitoring of the vns device showed likely dislodgement of the leads. It was recommended that the device was disabled, and appropriate adjustments were made. Clinic notes dated (b)(6) 2013 indicated that patient was having more frequent seizures; however, the physician noted that there was a very unconvincing description of the individual instances: the patient had a right hand tremor, and the mother pointed to it indicating a seizure. It was noted that the patient was treated with a powerful combination of anticonvulsants, including a very high dose of banzel. However, dosing and choice of anticonvulsants remained constricted by the interventions of the patient¿s mother who believed that the medications were causing behavioral issues and overlooked the prominent mental retardation. There was no specific injury or manipulation, but this was possible given the patient¿s mrdd and occasional aggression issues. X-rays had not been taken. Surgery is likely but has not taken place.
 
Event Description
On (b)(6) 2013, this vns patient underwent a full revision. The explanted lead and generator were returned on (b)(6) 2013 and are pending analysis.
 
Event Description
An analysis was performed on the returned lead portions. Note that a portion of the lead assembly (body) including the electrodes was not returned for analysis and therefore a complete evaluation could not be performed on the entire lead product. What appeared to be white deposits were observed on the outer silicone tubing. Eds (energy dispersion spectroscopy - provides chemical or element identity/composition analysis) was performed and identified the deposit as containing calcium, sodium, magnesium, potassium, zirconium, silicone, phosphorus and sulphur. Refer to attached eds sheet for additional information. The condition of the returned lead portions is consistent with conditions that typically exist following an explant procedure. No obvious anomalies were noted. The setscrew marks found on the lead connector pin provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no discontinuities were identified. Based on the findings in the product analysis lab, there is no evidence to suggest discontinuities in the returned portions of the device. The pulse generator was explanted/returned due to "prophylactic replacement". In the lab, the device output signal was monitored for more than 24-hrs, while the generator was placed in a simulated body temperature environment. Results showed no signs of variation in the pulse generator's output signal and demonstrated that the device provided the expected level of output current for the entire monitoring period. The pulse generator diagnostics were as expected for the programmed parameters. In addition, a comprehensive automated electrical evaluation showed that the pulse generator performed according to functional specifications. The battery, 2. 963 volts as measured during completion of test parameter 7. 16. 10. 2 (measured diagvbat) of the final electrical test, shows a non-ifi condition. The data in the diagaccumconsumed memory locations revealed that 11. 067% of the battery had been consumed. There were no performance or any other type of adverse conditions found with the pulse generator.

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« Reply #17 on: January 27, 2019, 04:45:57 AM »

Model Number 300-20
Event Date 03/14/2014
Event Type  Malfunction   
Manufacturer Narrative
(b)(4).
 
Event Description
The explanted generator and lead were returned to the manufacturer for analysis. There were no performance or any other type of adverse conditions found with the pulse generator. Review of the as-received internal device data showed that the last 25% change in the impedance value was on (b)(6) 2014. Analysis of the returned lead is currently underway.
 
Manufacturer Narrative
Date of event; corrected data: additional information indicates that high impedance event occurred at least on (b)(6) 2014.
 
Event Description
It was reported that pre-operative diagnostics for generator replacement surgery resulted in high impedance. It was reported that the patient's device was interrogated for the first time in several years. It was reported that both the generator and lead were replaced. The patient was in a motor vehicle accident in 2012; however, it was unknown if this contributed to the high impedance. An implant card was received indicating that the generator and lead were replaced due to lead discontinuity (>10,000 ohms) and near end of service. It was reported that the explanted devices were discarded by the explanting facility; therefore, no analysis can be performed.
 
Event Description
Analysis of the lead was completed on 10/09/2014. Note that the electrodes were not returned for analysis; therefore a complete evaluation could not be performed on the entire lead product. During the visual analysis of the returned 88mm portion the (+) marked connector quadfilar coil appeared to be broken approximately 13mm past the end of the torn connector silicone / inner silicone tubes. Scanning electron microscopy was performed and identified the area on three of the broken coil strands as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage, pitting on two of the broken coil strands, no pitting on one of the broken coil strands and evidence of a stress induced fracture (torsional appearance) which most likely completed the fracture was observed on one of the broken coil strands. The area on the fourth broken coil strand was identified as being mechanically damaged which prevented identification of the coil fracture type and no pitting. Pitting was observed on the coil surface. During the visual analysis of the returned 170mm portion the (-) unmarked connector quadfilar coil appeared to be broken approximately 2mm and 4mm from the end of the connector bifurcation. Scanning electron microscopy was performed on the (-) unmarked connector quadfilar coil break (found at 2mm) and identified the area on three of the broken coil strands as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage, no pitting and evidence of a stress induced fracture (torsional appearance) which most likely completed the fracture on two of the broken coil strands. Scanning electron microscopy was performed on the (-) unmarked connector quadfilar coil break (found at 4mm) and identified the area three of the broken coil strands as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage, no pitting and evidence of a stress induced fracture (torsional appearance) which most likely completed the fracture on one of the broken coil strands. The area on the fourth broken coil strand was identified as being mechanically damaged which prevented identification of the coil fracture type and no pitting. Pitting was observed on the coil surface. During the visual analysis of the returned 170mm portion the (+) marked connector quadfilar coil appeared to be broken approximately 4mm from the end of the connector bifurcation. Scanning electron microscopy was performed and identified the area as having evidence of a stress induced fracture (fatigue appearance) with mechanical damage, no pitting and evidence of a stress induced fracture (torsional appearance) which most likely completed the fracture on three of the broken coil strands. It is believed that stimulation was present for a certain period of time as evidenced by the presence of metal pitting. Low magnification sem analysis of the quadfilar coil shows characteristics typical of a lead discontinuity which may include: material fracture, rough or pitted surface, thinned material thickness, electro-etching or material dissolution. The abraded openings and slice marks found on the outer silicone tubing and the cut ends that were made during the explanted process, most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids found inside the outer silicone tubing. The slice mark found on one of the inner silicone tubes and the cut ends that were made during the explanted process, most likely provided the leakage path for the dried remnants of what appeared to have once been body fluids found inside the inner silicone tubes. What appeared to be white deposits were observed in various locations. Eds (energy dispersion spectroscopy - provides chemical or element identity/composition analysis) was performed and identified the deposit as containing silicon, phosphorus, sodium, magnesium, potassium, aluminum, sulphur, chlorine and calcium. With the exception of the observed discontinuities the condition of the returned lead portions is consistent with conditions that typically exist following an explant procedure. No other obvious anomalies were noted. The setscrew marks found on the lead connector pins provide evidence that, at one point in time, a good mechanical and electrical connection was present. Continuity checks of the returned lead portions were performed, during the visual analysis, and no other discontinuities were identified.
 
Manufacturer Narrative
Device failure is suspected, but did not cause or contribute to a death or serious injury.

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