title: Automatic Vagus Nerve Stimulation Triggered by Ictal Tachycardia: Clinical Outcomes and Device Performance--The U.S. E-37 Trial.
abstract: OBJECTIVE
  The Automatic Stimulation Mode (AutoStim) feature of the Model 106 Vagus Nerve Stimulation (VNS) Therapy System stimulates the left vagus nerve on detecting tachycardia. This study evaluates performance, safety of the AutoStim feature during a 3-5-day Epilepsy Monitoring Unit (EMU) stay and long- term clinical outcomes of the device stimulating in all modes.
  
  
  METHODS
  The E-37 protocol (NCT01846741) was a prospective, unblinded, U.S. multisite study of the AspireSR(®) in subjects with drug-resistant partial onset seizures and history of ictal tachycardia. VNS Normal and Magnet Modes stimulation were present at all times except during the EMU stay. Outpatient visits at 3, 6, and 12 months tracked seizure frequency, severity, quality of life, and adverse events.
  
  
  RESULTS
  Twenty implanted subjects (ages 21-69) experienced 89 seizures in the EMU. 28/38 (73.7%) of complex partial and secondarily generalized seizures exhibited ≥20% increase in heart rate change. 31/89 (34.8%) of seizures were treated by Automatic Stimulation on detection; 19/31 (61.3%) seizures ended during the stimulation with a median time from stimulation onset to seizure end of 35 sec. Mean duty cycle at six-months increased from 11% to 16%. At 12 months, quality of life and seizure severity scores improved, and responder rate was 50%. Common adverse events were dysphonia (n = 7), convulsion (n = 6), and oropharyngeal pain (n = 3).
  
  
  CONCLUSIONS
  The Model 106 performed as intended in the study population, was well tolerated and associated with clinical improvement from baseline. The study design did not allow determination of which factors were responsible for improvements.
authors.affiliation: Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Fisher
authors.affiliation: Department of Neurology, University of Utah, Salt Lake City, UT, USA.
authors.forename: Pegah
authors.initials: P
authors.lastname: Afra
authors.affiliation: Department of Neurology, Northwestern University, Chicago, IL, USA.
authors.forename: Micheal
authors.initials: M
authors.lastname: Macken
authors.affiliation: Department of Neurology, University of Michigan, Ann Arbor, MI, USA.
authors.forename: Daniela N
authors.initials: DN
authors.lastname: Minecan
authors.affiliation: University of Pittsburgh Comprehensive Epilepsy Center (UPCEC), Pittsburgh, PA, USA.
authors.forename: Anto
authors.initials: A
authors.lastname: Bagić
authors.affiliation: Department of Neurology, University of South Florida & Tampa General Hospital, Tampa, FL, USA.
authors.forename: Selim R
authors.initials: SR
authors.lastname: Benbadis
authors.affiliation: Department of Neurology, Emory University, Atlanta, GA, USA.
authors.forename: Sandra L
authors.initials: SL
authors.lastname: Helmers
authors.affiliation: Department of Neurology, Duke University Medical Center, Durham, NC, USA.
authors.forename: Saurabh R
authors.initials: SR
authors.lastname: Sinha
authors.affiliation: Department of Neurology, University of Texas Health Science Center at Houston, Houston, TX, USA.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Slater
authors.affiliation: Epilepsy Center, Barrow Neurological Institute, Phoenix, AZ, USA.
authors.forename: David
authors.initials: D
authors.lastname: Treiman
authors.affiliation: Cyberonics, Inc., Houston, TX, USA.
authors.forename: Jason
authors.initials: J
authors.lastname: Begnaud
authors.affiliation: Cyberonics, Inc., Houston, TX, USA.
authors.forename: Pradheep
authors.initials: P
authors.lastname: Raman
authors.affiliation: Cyberonics, Inc., Houston, TX, USA.
authors.forename: Bita
authors.initials: B
authors.lastname: Najimipour
mesh_terms: D000328:Adult; D000368:Aged; D000069279:Drug Resistant Epilepsy / Q000150:complications*; D004828:Epilepsies, Partial / Q000150:complications*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013610:Tachycardia / Q000209:etiology* / Q000628:therapy*; D016896:Treatment Outcome; D055536:Vagus Nerve Stimulation / Q000295:instrumentation / Q000379:methods*; D055815:Young Adult
keywords: AspireSR; VNS therapy system; ictal tachycardia; vagus nerve stimulation