title: Selective increase of cardiac neuronal sympathetic tone: a catheter-based access to modulate left ventricular contractility.
abstract: OBJECTIVE
  This study was designed to develop a technique to selectively increase the sympathetic tone to the heart by cardiac sympathetic nerve stimulation (SNS).
  
  
  BACKGROUND
  Access to the cardiac sympathetic neurons may allow modulating the adrenergic tone of the heart while avoiding systemic side effects.
  
  
  METHODS
  Cardiac sympathetic nerves course within neural sleeves along the subclavian artery. Because of this proximity, transvascular SNS was attempted with electrode catheters inside the subclavian artery in 16 pigs.
  
  
  RESULTS
  Right/left (R-/L-) SNS (20 Hz) during ventricular pacing at 200/min evoked a >100% increase of left ventricular systolic pressure (baseline: 51 +/- 1 mm Hg; L-SNS: 118 +/- 26 mm Hg; R-SNS: 116 +/- 33 mm Hg; p < 0.001) while systemic vascular resistance remained unchanged. There was a sigmoid dose-response curve with rapid on- and offset of the effect during SNS initiation/cessation. Positive inotropic effects persisted for 12 h of continued SNS (n = 4). Besides positive dromotropic effects, L-SNS/R-SNS yielded a 41% and 77% sinus rate increase, respectively.
  
  
  CONCLUSIONS
  The neural adrenergic tone to the heart can be selectively increased by catheter stimulation of cardiac efferent sympathetic nerves.
authors.affiliation: Department of Cardiology, University of Technology, Aachen, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Zarse
authors.forename: Jurgita
authors.initials: J
authors.lastname: Plisiene
authors.forename: Karl
authors.initials: K
authors.lastname: Mischke
authors.forename: Thomas
authors.initials: T
authors.lastname: Schimpf
authors.forename: Christian
authors.initials: C
authors.lastname: Knackstedt
authors.forename: Felix
authors.initials: F
authors.lastname: Gramley
authors.forename: Georg
authors.initials: G
authors.lastname: Mühlenbruch
authors.forename: Mathias
authors.initials: M
authors.lastname: Waldmann
authors.forename: Michael
authors.initials: M
authors.lastname: Schmid
authors.forename: Nima
authors.initials: N
authors.lastname: Hatam
authors.forename: Jürgen
authors.initials: J
authors.lastname: Graf
authors.forename: Dirk
authors.initials: D
authors.lastname: Schuster
authors.forename: Peter
authors.initials: P
authors.lastname: Hanrath
authors.forename: Dainius
authors.initials: D
authors.lastname: Pauza
authors.forename: Patrick
authors.initials: P
authors.lastname: Schauerte
mesh_terms: D000818:Animals; D006328:Cardiac Catheterization; D004558:Electric Stimulation / Q000379:methods*; D006321:Heart / Q000294:innervation*; D009200:Myocardial Contraction; D013552:Swine; D013564:Sympathetic Nervous System / Q000502:physiology*; D016277:Ventricular Function, Left