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Author Topic: VNS Kills  (Read 75947 times)
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dennis100
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« Reply #240 on: June 05, 2014, 11:50:47 AM »

Event Date 07/02/2006
Event Type Injury
Patient Outcome Life Threatening; Hospitalization
Event Description
Asystole related to malfunction of vagal nerve stimulator. Occurred at least 8 times.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/detail.cfm?mdrfoi__id=795000
« Last Edit: September 10, 2016, 05:42:28 AM by dennis100 » Logged
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« Reply #241 on: June 05, 2014, 11:51:24 AM »

Model Number 103
Event Type Injury
Manufacturer Narrative

Event Description
It was reported that a vns patient suffers from extreme tiredness and a very low heart rate (42-75bpm). These complaints started after she had changed the duty cycle. The patient will undergo a heart monitoring test (with the generator switched on and off). Review of the available programming and diagnostic history (from the implant date) showed normal diagnostic results. Attempts for additional relevant information have been unsuccessful to date.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=5750477
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« Reply #242 on: June 05, 2014, 11:57:04 AM »

Model Number 102
Event Date 01/11/2008
Event Type Injury
Event Description
Reporter indicated that a vns patient was experiencing 30 second periods of heart block associated with stimulation on times and subsequent arrhythmias. The patient has a prior history of syncope and heart rate irregularities. Diagnostic testing showed the device to be functioning properly. Ekg strips were evaluated and showed that the patient was experiencing a ventricular standstill. The device was programmed off.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/Detail.CFM?MDRFOI__ID=992788
« Last Edit: September 10, 2016, 05:43:36 AM by dennis100 » Logged
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« Reply #243 on: June 05, 2014, 11:58:21 AM »

Event Date 08/25/2008
Event Type Injury
Patient Outcome Required Intervention;
Event Description
It was reported to the manufacturer that the vns patient was experiencing tachycardia. The patient's heart rate was consistently around 99-108. The patient has her pacemaker implanted on the left and her vns generator on the right with more than 7-10 inches away. We were informed that every time the patient's vns device delivered stimulation, the patient's heart rate dropped and the pacemaker attempt to correct this by firing to increase heart rate. The physician suggested the patient turn the vns device off by taping the magnet over the generator. The patient was informed to visit with her neurologist and cardiologist to resolve the issue. Good faith attempts to obtain additional information regarding this event are underway.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=1175970
« Last Edit: September 10, 2016, 05:44:18 AM by dennis100 » Logged
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« Reply #244 on: June 05, 2014, 11:59:14 AM »

Model Number 105
Event Date 04/28/2014
Event Type Injury
Event Description
It was reported that during the patient's initial implant surgery on (b)(6) 2014, there were difficulties identifying the nerve due to a structure with a similar appearance. Therefore, following placement of the electrodes on the structure believed to be the vagus nerve, the patient¿s generator was programmed on (output current - 2ma) in an attempt to induce bradycardia and therefore identify if the electrodes were indeed on the vagus nerve. Bradycardia was observed as intended and resolved without intervention. Therefore, it was concluded that the electrodes were properly placed. The generator was inadvertently not programmed off after the tests were completed due to communication difficulties with the programming system. As a result, the patient experienced painful stimulation, neck muscle spasms, and severe coughing until the surgeon programmed the patient's generator off and administered morphine the following day.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=3825172
« Last Edit: September 06, 2016, 04:47:28 AM by dennis100 » Logged
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« Reply #245 on: June 05, 2014, 11:59:47 AM »

Model Number 102
Event Date 04/01/2009
Event Type  Injury   
Event Description 
It was reported that the pt was experiencing an increase in seizures above pre-vns baseline. During these seizures, the pt was having episodes of asystole. Pt was hospitalized and implanted with a pacemaker as a result. Per the treating medical professional, it is unk if the increase in seizures and asystole are related to vns or stimulation. Device diagnostics are all within normal limits. A battery life calculation was run and shows there to be approximately 1. 61 years remaining until end of service. The pt's medication levels were measured and were at zero which indicates the pt has not been compliant with her medication. It is unk at this time if this had an effect on the seizures and/or asystole. Pt will be monitored and no further interventions are planned at this time. All attempts for additional info have been unsuccessful to date.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/Detail.CFM?MDRFOI__ID=1373576
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« Reply #246 on: June 05, 2014, 12:00:37 PM »

Event Date 05/01/2006
Event Type Injury
Patient Outcome Required Intervention
Event Description
Reporter indicated that pt began to experience episodes of syncope and asystole approximately six years post vns implant. The pt reported feeling the need to cough, after which he reportedly lost consciousness. Approximately two months after, the onset of symptoms, the pt was hospitalized for eval of the syncope episodes, at which time and ekg revealed episodes of asystole that coincided with device stimulation cycles; however, not every stimulation cycle would produce this event. The vns therapy system was then programmed to off, after which a repeat ekg was normal. The pt did not experience any further episodes of syncope or asystole in the absence of the vns therapy. Eval by cardiologist did not reveal any abnormalities with the pt's heart. The device remains programmed to off. Both the cardiologist and the neurologist believe that the reported events were caused by the stimulation of the vagus nerve. There had been no recent changes to programmed device settings; however, inderal had recently been added to the pt's medication regimen for treatment of mild hypertension.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/detail.cfm?mdrfoi__id=1629932
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« Reply #247 on: June 05, 2014, 12:01:39 PM »

Event Date 01/10/2006
Event Type Injury
Patient Outcome Required Intervention
Event Description
Reporter indicated that pt suddenly began to experience serious drop attacks unrelated to his epilepsy. The pt had been implanted for approx 29 months when the drop attacks began and had experienced good efficacy with the vns therapy regarding his seizure control. There had been no changes to either programmed parameters or medication regimen for approx one year. The pt was hospitalized, during which time it was discovered that he was experiencing episodes of bradycardia leading to asystole during device stimulation cycles. The pt also experienced several episodes of syncope during this time. No heart condition has been reported that the pt's device was functioning normally, although specific device diagnostic test results were not provided by physician. Stimulation has been discontinued and explant of the ncp system is planned. The episodes of syncope have reportedly resolved since the device was programmed to off; however the pt's seizures have somewhat worsened in the absence of the vns therapy (to approx 1 seizure per wk). Treating physician indicates that the reported events appear to be related to device stimulation ("vagally-induced heart block and sinus bradycardia") but does not know why the pt began to experience these events after more than two yrs of successful vns therapy.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/Detail.CFM?MDRFOI__ID=689307
« Last Edit: August 29, 2016, 01:12:45 PM by dennis100 » Logged
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« Reply #248 on: June 05, 2014, 12:02:17 PM »

Event Date 03/03/2008
Event Type Injury
Patient Outcome Required Intervention
Event Description
Initial reporter called to ask if manufacturer had any info on vns pt's experiencing asystole caused by swiping their magnet or stimulation. It was additionally reported "a pt had a seizure and the nurse swiped with a magnet. Afterwards the pt went into asystole, which lasted several seconds. The pt was in the hospital due to seizures and connected to a monitor so they were able to see it. " the pt's seizure rate was above their pre vns seizure rate and was a change for the pt. No further info has been attained from the site after good faith attempts have been made.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/Detail.CFM?MDRFOI__ID=1022608
« Last Edit: August 29, 2016, 01:13:04 PM by dennis100 » Logged
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« Reply #249 on: June 05, 2014, 12:03:27 PM »

Event Date 01/01/2006
Event Type Injury
Patient Outcome Required Intervention
Event Description
Vns pt was hospitalized with asystole. While hospitalized, the pt's device was programmed to off, after which his condition stabilized. While attempting to reinitiate device stimulation, the pt exhibited asystole again.Treating physician programmed the device back to off and does not plan to reinitiate stimulation. The pt had reportedly been experiencing good seizure control with the vns therapy and his device had been programmed to 3. 0ma normal mode output current "for quite a while". It was reported that since the incident, the pt is unable to tolerate even lower levels of stimulation, due to the cardiac condition. The pt is non-verbal and cannot communicate whether device stimulation feels abnormal. The pt does not have any pre-existing conditions that may have precipitated the reported event and there had been no recent changes to the pt's medication regimen.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/Detail.CFM?MDRFOI__ID=675911
« Last Edit: August 29, 2016, 01:13:25 PM by dennis100 » Logged
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« Reply #250 on: June 05, 2014, 12:05:00 PM »

Model Number 106
Event Date 06/29/2016
Event Type Injury
Manufacturer Narrative
(b)(4).

Event Description
It was reported that the patient started having several bradycardia and asystole events soon after a full vns replacement surgery. The patient was admitted to the hospital in relation to these events. The vns generator was confirmed to have been enabled after the replacement surgery. There were no cardiac issues noted during the implant or testing. Post-operative diagnostics were reported to be within normal limits. The vns magnet was placed over the device to inhibit stimulation and the cardiac events did not resolve. The treating physician concluded that the cardiac events were not related to vns stimulation. The relation between the cardiac events and vns surgery has not been clarified to date. The patient was subsequently evaluated for a pacemaker implant, and the case was completed. Attempts for additional pertinent information have been unsuccessful to date.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=5817715
« Last Edit: August 29, 2016, 02:49:11 PM by dennis100 » Logged
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« Reply #251 on: June 05, 2014, 01:25:55 PM »

Event Date 01/07/2011
Event Type Injury
Patient Outcome Life Threatening; Required Intervention
Event Description
It was reported that the pt went to the clinic to have the vns turned on. The pt was programmed to 0. 25 ma and could feel stimulation. When the nurse left the room for a few minutes, the pt's parent alerted that the pt had collapsed on the floor, was non-responsive and chalky white. The nurse thought this may have been due to the vns and turned the device off. The pt was resuscitated and transferred to intensive care unit and now reported to be recovering. The pt's heart rate after device switched off and during resuscitation was 60 bpm. There are no further plans to date.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=1979719
« Last Edit: August 29, 2016, 01:13:45 PM by dennis100 » Logged
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« Reply #252 on: June 05, 2014, 01:26:51 PM »

Event Date 06/27/2011
Event Type Injury
Patient Outcome Required Intervention;
Event Description
It was initially reported that during a generator replacement procedure the pt was experiencing tachycardia. The surgeon performed diagnostics on the pt, and then proceeded to program the pt to 0. 25ma. The pt then started showing signs of tachycardia. At that time, the pt's device was disabled and the tachycardia resolved. The exact diagnostic results are not known. It is also unk if any other settings, besides the programming of the output current, were changed. Attempts for add'l info have been unsuccessful to date.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/detail.cfm?mdrfoi__id=2190804
« Last Edit: September 01, 2016, 03:34:19 AM by dennis100 » Logged
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« Reply #253 on: June 05, 2014, 01:51:46 PM »

Model Number 102
Event Date 05/01/2013
Event Type Injury
Event Description
It was reported that the patient had episodes that felt like she was about to pass out and when her heart rate was monitored by her caregiver it was over 200 bpm. It was reported that the patient¿s heart rate was higher when she laid on her right side than when lying on her left side. The increased heart rate was noted to be present for approximately 28 minutes. The patient was admitted into a cardiac unit. According to the patient¿s caregiver, the device was programmed off while hospitalized and that the heart rate ¿issues¿ went away. The device has not yet been programmed back on. Attempts to obtain additional information have been unsuccessful to date.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/detail.cfm?mdrfoi__id=3286618
« Last Edit: August 31, 2016, 01:31:53 AM by dennis100 » Logged
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« Reply #254 on: June 06, 2014, 06:45:20 PM »

Model Number 102
Event Date 06/01/2008
Event Type Injury
Event Description
It was reported that a vns pt was experiencing increase in seizures and heart problems. The pt had been admitted to the hospital due to depacod intoxication from medication. In the hospital, it was observed that the pt had spells of bradycardia believed to be due to vns therapy. The magnet was placed over the generator to turn off vns stimulation. It was then observed that the pt had episodes of sinus arrest lasting 5-6 seconds and occurring frequently. The er physician was unsure if the magnet had actually stopped vns stimulation and requested that a doctor familiar with vns would program the device off to determine if the occurrences of sinus block were related to vns therapy. Good faith attempts to obtain additional info have been unsuccessful to date.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=1096491
« Last Edit: August 31, 2016, 01:48:05 AM by dennis100 » Logged
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« Reply #255 on: June 07, 2014, 01:44:00 PM »

Event Date 12/04/2008
Event Type Injury
Patient Outcome Life Threatening; Required Intervention
Event Description
It was reported in a scientific article that a vns patient, who had been receiving vns therapy for nine years without complaint, was admitted to the hospital for the control of an episode status epilepticus, an event not uncommon for the patient, for which medication was administered. The patient experienced an increase in seizures during the hospital stay and eeg monitoring revealed the occurrence of periodic cardiac changes with bradyarrhythmia and often severe asystolia due to atrium ventricular block, which coincided with stimulation. The patient was admitted to the cardiac intensive care unit and underwent holter monitorization, because the periodicity of the bradyarrhythmias was the same as that of the ncp stimulation (around 30 s every 5. 5 min), the ncp was stopped. Once the device was disabled, the reported arrhythmia event resolved. The reporter states that though there appears to be a clear relationship to vns therapy, other contributing factors were believed to be present. These factors include the addition of levetiracetam, which had a notable arrhythmic effect on the patient. The author also suggests that the patient's status episode may have predisposed the patient to the vns-related cardiac arrhythmia.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/Detail.CFM?MDRFOI__ID=1276878
« Last Edit: September 06, 2016, 04:48:25 AM by dennis100 » Logged
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« Reply #256 on: August 31, 2016, 01:49:56 AM »

Model Number 102
Device Problem Device operates differently than expected
Event Date 07/04/2015
Event Type Injury
Manufacturer Narrative

Event Description
Monophasic cardioversion was performed at 100j with patches, one on the left-medial chest and one on the upper-middle of the back. According to the physician who performed the cardioversion, the patient was coughing during the procedure. After the cardioversion, the patient kept coughing and had repeated, regular asystole periods that were 14 seconds long. The physician who performed the cardioversion believed that vns stimulation led to ventricular tachycardia and asystole. Attempts for further information have been made, but no relevant information has been received to date.

Event Description
It was reported on (b)(6) 2015 that a patient had cardioversion performed and then starting having severe coughing every 90 seconds during stimulation. The nurse believed that the coughing was related to vns stimulation. The patient's magnet was placed over the generator to inhibit stimulation. The patient was then transported to another hospital, where he experienced bradycardia associated with stimulation. The patient's generator was disabled, which resolved the bradycardia. Attempts for further information have been made but no relevant information has been received to date.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=4950732
« Last Edit: September 01, 2016, 12:20:38 AM by dennis100 » Logged
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« Reply #257 on: September 01, 2016, 12:21:30 AM »

Event Date 11/27/2013
Event Type Injury
Manufacturer Narrative

Event Description
A maude event report ((b)(4)) was received indicating that the patient was found unresponsive with a heart rate of 16 bpm. It was reported that the patient was hospitalized and intubated and that the patient was released several days later. It was also noted that the patient has experienced an increase in seizures for the past few months and that the seizures are different than prior seizures. It was reported that the patient no longer experiences her usual aura and no post-ictal state. It was reported that vns induced asystole/bradycardia is suspected. No additional information has been received to date.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=3651797
« Last Edit: September 04, 2016, 04:48:37 AM by dennis100 » Logged
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« Reply #258 on: September 01, 2016, 01:01:31 AM »

Model Number 103
Event Date 09/06/2012
Event Type Injury
Event Description
Attempts for additional information have been unsuccessful to date.

Event Description
It was reported by a physician that the patient was experiencing bradycardia while monitored telemetry machine. The bradycardia was occurring every 1. 8minutes. The magnet was taped over the device and left for twelve hours. Upon removal of the magnet, the patient experience asystole. The heart rhythm was regained when the magnet was placed back over the device. Attempts for additional information are in progress.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=2772615
« Last Edit: September 04, 2016, 04:50:07 AM by dennis100 » Logged
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« Reply #259 on: September 01, 2016, 01:02:13 AM »

Model Number 102
Event Date 09/19/2012
Event Type Injury
Event Description
A fax was received on (b)(6) 2012, from the patient's physician. The fax indicated that additional interventions included "cardiology consult and simultaneous". The patient did not have a previous history or family history of cardiac events. The patient's pre-existing conditions included neonatal cerebral abscesses, infantile spasms, intractable epilepsy, and global developmental delay. The patient experienced bradycardia. Prior to the event, the patient's heart rate was 109 bpm. During the event, the patient's heart rate was 104 bpm.

Event Description
On (b)(6) 2012, it was reported that this vns patient experienced an arrhythmia during initial implant surgery that day. The patient was successfully implanted. An in-pocket system diagnostic was normal, and a final interrogation confirmed that the normal mode and magnet mode output currents were 0. 00 ma. During the first system diagnostic test, the surgeon noticed a heart arrhythmia during the vns stimulation period. He stated it was not bradycardia, just an abnormal arrhythmia. The system diagnostic test was repeated multiple times, all tests were within normal limits, and the arrhythmia was still present. Following each test, the surgeon attempted to re-position the coils on the nerve to maximize the distance between the coils and the cervical branch of the vagus nerve. He stated the arrhythmia was minimized but was still present after the repositioning of the coils. He stated this was likely due to the very small size of the patient and the short length of nerve he had to work. Attempts for additional information have been unsuccessful.

https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=2792641
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« Reply #260 on: September 01, 2016, 01:03:03 AM »

Event Date 01/01/1996
Event Type Injury
Patient Outcome Life Threatening;
Manufacturer Narrative
Han p, frei mg, osorio i. Probable mechanisms of action of vagus nerve stimulation in humans with epilepsy: is a window into the brain [abstract]? epilepsia 1996;37 (5suppl):83s.

Event Description
It was reported in an article reviewed by manufacturer that vns patients are experiencing bradycardia and tachycardia with stimulation. A decrease in r-r variability is sometimes seen in patients at risk of sudden cardiac death. Attempts for further info are in progress.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/detail.cfm?mdrfoi__id=1143661

« Last Edit: September 01, 2016, 03:03:38 AM by dennis100 » Logged
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« Reply #261 on: September 01, 2016, 03:04:28 AM »

Event Date 02/25/2008
Event Type Injury
Patient Outcome Required Intervention;
Event Description
Reporter indicated a vns pt experienced an increased heart rate with stimulation. Diagnostic testing was within normal limits and the physician had not changed the patient's settings "in a while". A cardiologist confirmed a heart rate of 120-140 only during stimulation. However, this was not with every stimulation, it was just with some of the stimulations. The cardiologist believes the increased heart rate is related to vns therapy. The patient's vns therapy system was disabled and all the symptoms have gone away. The physician stated the vns was helping with the patient's epilepsy and depression and has since started working as a social worker. Good faith attempts to obtain additional info have been unsuccessful to date.

http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfMAUDE/detail.cfm?mdrfoi__id=1058502
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« Reply #262 on: September 02, 2016, 12:33:23 AM »

Left Cervical Vagal Nerve Stimulation Suppresses Cardiac Sympathetic Tone

Conclusion: Patients with left cervical VNS had lower heart rate and iSKNA than patients without VNS. These findings are consistent with those observed in ambulatory canines, and suggest that chronic intermittent VNS can suppress cardiac sympathetic tone in human.

http://circ.ahajournals.org/content/132/Suppl_3/A16255.short
« Last Edit: September 11, 2016, 04:12:05 AM by dennis100 » Logged
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« Reply #263 on: September 03, 2016, 02:49:37 AM »

THE EFFECTS OF REDUCED CARDIAC SYMPATHETIC TONE ON MYOCARDIAL FUNCTION
First paragraph:

Stimuli mediated over cardiac sympathetic nerves increase the work output of the heart and the contractility of the myocardium. Such stimuli increase ventricular performance so that more external work is produced at a lower filling pressure. Stimuli mediated over the vagus nerves appear to decrease ventricular performance. Recent work indicates that sympathetic stimulation increases and that vagal stimulation decreases the vigor of atrial contraction. The data from these same experiments show also that the relation between mean atrial pressure and stroke work is determined by atrial as well as ventricular function.

http://www.jci.org/articles/view/104283/pdf
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« Reply #264 on: September 04, 2016, 12:32:24 AM »

Regulation of Ventricular Contraction Influence of Cardiac Sympathetic and Vagal Nerve Stimulation on Atrial and Ventricular Dynamics

Summary
At constant heart rates, efferent stimulation of the vagus nerve and of the left stellate ganglion revealed the following:

1. Vagal stimulation exerts a profound depressant effect on the strength of the atrial contraction and can thereby influence ventricular filling and ventricular stroke work; it elevates mean atrial pressure at any given level of ventricular stroke work. This occurs under experimental conditions wherein the vagal stimulation used does not produce an alteration in the performance characteristics of the ventricle. The effects of vagal stimulation are blocked by atropine.

2. Stellate ganglion stimulation or norepinephrine infusion augments the strength of atrial contraction and thus the atrial contribution to ventricular filling. The augmented atrial contraction takes place in a shorter period of time.

3. Stellate ganglion stimulation or norepinephrine infusion increases the external stroke work and power produced by the ventricle from any given mean atrial pressure and from any given end-diastolic pressure or fiber length.

4. There is a family of curves representing the relation between end-diastolic fiber length and stroke work, as well as a family of curves representing the relation between mean atrial or end-diastolic pressure and stroke work.

5. When taken together with the well-known sympathetic and parasympathetic effects on heart rate, the above data are believed to comprise a reasonably comprehensive description of the means available to the central nervous system for directly inducing acute changes in the activity of the heart.

http://circres.ahajournals.org/content/8/5/1108.full.pdf
« Last Edit: September 11, 2016, 04:13:18 AM by dennis100 » Logged
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« Reply #265 on: September 05, 2016, 12:55:52 AM »

How can damage to the vagus nerve cause immediate death?

Nervus vagus belongs to parasympathetic nervous system which inhibits the contraction of heart, decreases its excitability and frequency of generated nerve impulses in heart. By overstimulating n.vagus these effects on heart are more intense - it could lead to total inhibiton of heart contractions, which would eventually lead to death within a little while.

Very intense slap behind ear or intensive pressure on neck area could lead to death as n.vagus is overstimulated. It is very rare though.

http://wiki.answers.com/Q/How_can_damage_to_the_vagus_nerve_cause_immediate_death
« Last Edit: September 11, 2016, 04:14:00 AM by dennis100 » Logged
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« Reply #266 on: September 11, 2016, 04:15:00 AM »

I was nearly killed by that thing. Don't let what happened to me happen to you!

My Story:
Reader's Digest version.
http://www.vnsmessageboard.com/index.php/topic,4490.0.html

Vagal Inhibition
http://healthdrip.com/vagal-inhibition/
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