Med Hypotheses. 2010 Dec 6. [Epub ahead of print]

Vagus nerve stimulation as a strategy to prevent and manage metabolic syndrome.

Das UN.

School of Biotechnology, Jawaharlal Nehru Technological University, Kakinada 533 003, India; UND Life Sciences, 13800 Fairhill Road, #321, Shaker Heights, OH 44120, USA.

Abstract

An increase in pro-inflammatory cytokines, decrease in endothelial nitric oxide (eNO) and adiponectin levels and an alteration in hypothalamic peptides and gastrointestinal hormones such as incretins and cholecystokinin that regulate satiety, hunger, and food intake occur in metabolic syndrome. Thus, metabolic syndrome is a low-grade systemic inflammatory condition and could be due to inappropriate cross-talk between the peripheral tissues and the hypothalamic centers implying that methods designed to restore these two abnormalities to normal could be of significant benefit in metabolic syndrome. Vagus nerve stimulation has been shown to suppress inflammation and acetylcholine, the principal vagal neurotransmitter, modulates the actions of several hypothalamic peptides and incretins and cholecystokinin. Based on these evidences, it is proposed that vagus nerve stimulation could be of significant benefit in the management of the metabolic syndrome.

PMID: 21144670 [PubMed - as supplied by publisher]

http://www.ncbi.nlm.nih.gov/pubmed/21144670

Epilepsy Behav. 2010 Dec 6. [Epub ahead of print]

Vagus nerve stimulation in 436 consecutive patients with treatment-resistant epilepsy: Long-term outcomes and predictors of response.

Elliott RE, Morsi A, Kalhorn SP, Marcus J, Sellin J, Kang M, Silverberg A, Rivera E, Geller E, Carlson C, Devinsky O, Doyle WK.

Department of Neurosurgery, New York University Langone Medical Center, New York, NY, USA.

Abstract

OBJECTIVE: The goal of this study was to assess the efficacy and safety of vagus nerve stimulation in a consecutive series of adults and children with treatment-resistant epilepsy (TRE).

METHODS: In this retrospective review of a prospectively created database of 436 consecutive patients who underwent vagus nerve stimulator implantation for TRE between November 1997 and April 2008, there were 220 (50.5%) females and 216 (49.5%) males ranging in age from 1 to 76years at the time of implantation (mean: 29.0±16.5). Thirty-three patients (7.6%) in the primary implantation group had inadequate follow-up (<3months from implantation) and three patients had early device removal because of infection and were excluded from seizure control outcome analyses.

RESULTS: Duration of vagus nerve stimulation treatment varied from 10days to 11years (mean: 4.94years). Mean seizure frequency significantly improved following implantation (mean reduction: 55.8%, P<0.0001). Seizure control ≥90% was achieved in 90 patients (22.5%), ≥75% seizure control in 162 patients (40.5%), ≥50% improvement in 255 patients (63.75%), and <50% improvement in 145 patients (36.25%). Permanent injury to the vagus nerve occurred in 2.8% of patients.

CONCLUSION: Vagus nerve stimulation is a safe and effective palliative treatment option for focal and generalized TRE in adults and children. When used in conjunction with a multidisciplinary and multimodality treatment regimen including aggressive antiepileptic drug regimens and epilepsy surgery when appropriate, more than 60% of patients with TRE experienced at least a 50% reduction in seizure burden. Good results were seen in patients with non-U.S. Food and Drug Administration-approved indications. Prospective, randomized trials are needed for patients with generalized epilepsies and for younger children to potentially expand the number of patients who may benefit from this palliative treatment.

http://www.ncbi.nlm.nih.gov/pubmed/21144802

Research Nerve Stimulation Therapy May Improve Outcomes and Reduce Healthcare Costs...

From HealthNewsDigest.com

 

Research Nerve Stimulation Therapy May Improve Outcomes and Reduce Healthcare Costs for Epilepsy

By

Dec 6, 2010 - 3:37:16 PM

(HealthNewsDigest.com) - ATLANTA – The use of nerve stimulation therapy
in patients with refractory epilepsy is associated with a lower occurrence of
epilepsy-related health problems and a lower use of healthcare resources,
according to a new study from the Emory University School of Medicine.
Refractory epilepsy is the occurrence of seizures that are not controlled with
medication alone.

Findings of the study were presented Dec. 5 at the American Epilepsy Society
Meeting in San Antonio, Texas. Sandra L. Helmers, MD, MPH, the R. Edward
Faught, MD, professor of neurology at Emory School of Medicine, conducted the
retrospective study of 1,655 patients treated with vagus nerve stimulation
(VNS) therapy from 1997 to 2009.

Using data from five Medicaid state claims databases, including Florida, Iowa,
Kansas, Missouri and New Jersey, the study is the first to review the long-term
medical and economic impact of VNS therapy for treatment of refractory epilepsy
in a clinical setting.

VNS therapy is an adjunctive therapy to antiepileptic drugs in patients 12
years or older and the only FDA-approved implantable medical device for the
treatment of refractory epilepsy. An implanted stimulator sends electric
impulses to the left vagus nerve in the neck via a lead wire implanted under
the skin.

“Poorly controlled seizures are an important risk factor for mortality in
people with epilepsy and put patients at higher risk of physical injuries such
as fractures or head injuries, as well as morbidities including depression and
anxiety,” says Helmers.

“The results of this study demonstrate that with VNS therapy for patients with
refractory epilepsy there may be improved clinical outcomes for patients that
subsequently result in significant savings for the healthcare system.”

The study evaluated epilepsy-related health problems such as frequency of
fractures and head trauma related to seizures. It also reviewed patient data
for healthcare utilization including seizure-related and non-seizure-related
emergency room visits, outpatient services, neurology services, and factors
such as length of hospital stay and prescription drug claims.

Study results confirmed that use of VNS therapy in patients with refractory
epilepsy is associated with:

A lower occurrence of epilepsy-related co-morbidities. Patients experienced
fewer injuries and other health issues after being implanted with VNS therapy,
compared to the period before VNS implantation.

A lower utilization of healthcare. All-cause hospitalizations and emergency
room visits significantly decreased over time after implantation with VNS
therapy compared to the six months prior to implantation.

Significant longer term cost savings. With a reduction in healthcare
utilization and co-morbidities as a result of VNS therapy, there is a
significant net total healthcare cost savings beginning at 1.5 years after
implantation. The study found that average quarterly total healthcare costs
were reduced approximately 28 percent, from an average of $19,945 pre-VNS
implantation to $14,316 at 1.5 years after implantation.

“While there are initial costs to VNS therapy including the surgical procedure
and the cost of the device, our study finds that the cost savings of VNS are
usually seen in about 18 months,” says Helmers. “By reducing overall healthcare
utilization such as emergency room visits, VNS therapy becomes a reasonable
option for patients with medically refractory epilepsy.”

http://www.healthnewsdigest.com/news/Research_270/Nerve_Stimulation_Therapy_May_Improve_Outcomes_and_Reduce_Healthcare_Costs_for_Epilepsy.shtml

 

Epilepsy Res. 2010 Dec 1. [Epub ahead of print]

Magnetoencephalography in epilepsy patients carrying a vagus nerve stimulator.

Carrette E, De Tiège X, De Beeck MO, De Herdt V, Meurs A, Legros B, Raedt R, Deblaere K, Van Roost D, Bourguignon M, Goldman S, Boon P, Van Bogaert P, Vonck K.

Reference Center for Refractory Epilepsy, Department of Neurology, Ghent University Hospital, De Pintelaan 185, 9000 Gent, Belgium.

Abstract

Due to technical constraints, magnetoencephalography (MEG) is challenging in vagus nerve stimulation (VNS) patients. This study evaluates (1) the feasibility of MEG in VNS patients and (2) the added value of MEG in their presurgical evaluation (PE). Ten VNS patients were studied by MEG using the spatiotemporal signal space separation (tSSS) method. Equivalent current dipoles (ECD) were classified "clustered"/"scattered". It was evaluated whether MEG (1) confirmed localisation of the hypothesized epileptogenic zone (HEZ), (2) improved delineation of the HEZ, or (3) identified 1 out of multiple HEZs. Finally it was evaluated whether adding MEG to the PE improved patient management by changing or supporting the hypothesis. In 7/10 patients, tSSS allowed to obtain interpretable MEG data, with interictal epileptiform discharges in 6/7. ECD clustered within 1 lobe in 4/6; confirming the localisation of the HEZ in 2/4 and improving delineation of the HEZ in 2/4. When ECD clustered within 2 lobes (1/6) or were scattered (1/6), MEG could not identify 1 out of multiple HEZs. In 2 patients, MEG changed management to invasive video-EEG monitoring (IVEM) and resective surgery (RS). In 4 patients, MEG further supported the management; IVEM in 2/4 and unsuitability for RS in 2/4. So far IVEM, performed in 2, resulted into RS. This study demonstrates the feasibility of MEG in VNS patients. MEG changed management in 20% and further supported the proposed management in 40% illustrating the clinical value of MEG in the PE of VNS patients.

PMID: 21129918 [PubMed - as supplied by publisher]

http://www.ncbi.nlm.nih.gov/pubmed/21130042

Epilepsy Behav. 2010 Dec 1. [Epub ahead of print]

Vagus nerve stimulator treatment in adult-onset Rasmussen's encephalitis.

Grujic J, Bien CG, Pollo C, Rossetti AO.

Service de Neurologie, Département de Neurosciences Cliniques, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Switzerland.

Abstract

We describe a patient with adult-onset Rasmussen's encephalitis (RE) responsive to vagus nerve stimulation. This previously healthy woman developed RE in the right hemisphere at the age of 27. Despite antiepileptic drug polytherapy, she continued to experience subcontinuous, simple-partial left-sided motor seizures and slowly progressive cognitive impairment. Resective surgery was not considered owing to the preservation of left motor skills. She was implanted with a vagus nerve stimulator at the age of 41; after 6months she experienced a greater than 50% reduction in seizure frequency, which persisted over 2years together with improvement of her neurological and cognitive status.

PMID: 21130042 [PubMed - as supplied by publisher]

http://www.ncbi.nlm.nih.gov/pubmed/21130042

Heart Fail Rev. 2010 Dec 3. [Epub ahead of print]

Vagus nerve stimulation in experimental heart failure.

Sabbah HN, Ilsar I, Zaretsky A, Rastogi S, Wang M, Gupta RC.

Department of Medicine, Division of Cardiovascular Medicine, Henry Ford Heart and Vascular Institute, Henry Ford Hospital, 2799 West Grand Boulevard, Detroit, MI, 48202, USA, hsabbah1@hfhs.org.

Abstract

Chronic heart failure (HF) is associated with autonomic dysregulation characterized by a sustained increase in sympathetic drive and by withdrawal of parasympathetic activity. Sympathetic overdrive and increased heart rate are predictors of poor long-term outcome in patients with HF. Considerable evidence exists that supports the use of pharmacologic agents that partially inhibit sympathetic activity as effective long-term therapy for patients with HF; the classic example is the wide use of selective and non-selective beta-adrenergic receptor blockers. In contrast, modulation of parasympathetic activation as potential therapy for HF has received only limited attention over the years given its complex cardiovascular effects. In this article, we review the results of recent experimental animal studies that provide support for the possible use of electrical Vagus nerve stimulation (VNS) as a long-term therapy for the treatment of chronic HF. In addition to exploring the effects of chronic VNS on left ventricular (LV) function, the review will also address the effects of VNS on potential modifiers of the HF state that include cytokine production and nitric oxide elaboration. Finally, we will briefly review other nerve stimulation approaches which is also currently under investigation as potential therapeutic modalities for treating chronic HF.

PMID: 21128115 [PubMed - as supplied by publisher

http://www.ncbi.nlm.nih.gov/pubmed/21128115

Neurosurgery. 2010 Dec;67 Operative Neurosurgery, 2:ons457-ons460.

Revision of Vagal Nerve Stimulator Electrodes Through a Posterior Cervical Triangle Approach: Technical Note.

Oʼneill BR, Wilberger JE.

1Division of Pediatric Neurosurgery, The Children's Hospital, University of Colorado, Aurora, Colorado 2Department of Neurosurgery, Allegheny General Hospital, Drexel University School of Medicine, Pittsburgh, Pennsylvania.

Abstract

BACK GROUND:: We describe an approach to vagal nerve stimulator (VNS) lead replacement through the posterior cervical triangle. Scar around the structures of the carotid sheath is avoided and new leads are placed on a pristine section of the vagus nerve proximal to the original site.

CLINICAL PRESENTATION:: Skin incision from the implantation surgery is incorporated and extended to allow access to the posterior border of the sternocleidomastoid muscle (SCM). Dissection proceeds along the posterior border of the SCM. The SCM and jugular vein are retracted anterior to expose a fresh segment of the vagal nerve immediately superficial to the carotid artery and proximal to the original electrode site. Once the nerve is adequately exposed, electrode placement proceeds in the standard fashion. Dysfunctional electrodes are left in place, and the lead wire is cut as near the electrodes as can be easily accessed. Three patients have undergone lead revision with this approach. Lead placement was successful and free from complications in all cases.

CONCLUSION:: The posterior cervical triangle approach provides a virgin dissection plane for VNS revision.

PMID: 21099572 [PubMed - as supplied by publisher

http://www.ncbi.nlm.nih.gov/pubmed/21099572