title: Effects of percutaneous stimulation of both sympathetic and parasympathetic cardiac autonomic nerves on cardiac function in dogs.
abstract: OBJECTIVE
  Augmentation of left ventricular (LV) contractility and heart rate (HR) by sympathetic nerve stimulation and amelioration of heart failure by vagal nerve stimulation has been reported. However, the effects of concomitant electrical stimulation of both sympathetic and parasympathetic cardiac nerves in tissues such as those of the cardiac plexus remain unclear. This study sought to assess acute changes in cardiac function and hemodynamics in response to endovascular cardiac plexus stimulation (CPS).
  
  
  METHODS
  Twelve dogs received endovascular CPS via a bipolar catheter within the right pulmonary artery. Stimulation frequency (20 Hz) and pulse width (4 milliseconds) were fixed; voltage varied (range, 15-60 V).
  
  
  RESULTS
  Results fell into three categories: 1, no response (n = 4); 2, an increase in systemic arterial pressure that was dependent on electrode placement (n = 4); and 3, a very reproducible and stable increase in aortic pressure (n = 4). In the third group, mean systolic aortic pressures, maximum value of the first derivative of LV pressure, and LV stroke work increased with stimulation (P < 0.02 for all parameters) as did cardiac output, end-systolic elastance, and preload recruitable stroke work (P = 0.03). Systemic and pulmonary vascular resistance, central venous pressure, pulmonary arterial pressure, and HR remained unchanged (P > 0.05).
  
  
  CONCLUSIONS
  In contrast to conventional inotropic agents, endovascular CPS induced significant and selective increases in LV contractility without increasing HR. Efforts to optimize electrode placement and fixation will improve the reproducibility of endovascular CPS treatment.
authors.affiliation: Department of Biomedical Engineering, Cleveland Clinic, Cleveland, OH 44195, USA.
authors.forename: Mariko
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Sakurai
authors.forename: Tohru
authors.initials: T
authors.lastname: Takaseya
authors.forename: Akira
authors.initials: A
authors.lastname: Shiose
authors.forename: Hyun-Il
authors.initials: HI
authors.lastname: Kim
authors.forename: Masako
authors.initials: M
authors.lastname: Fujiki
authors.forename: Jamshid H
authors.initials: JH
authors.lastname: Karimov
authors.forename: Raymond
authors.initials: R
authors.lastname: Dessoffy
authors.forename: Alex
authors.initials: A
authors.lastname: Massiello
authors.forename: Allen G
authors.initials: AG
authors.lastname: Borowski
authors.forename: David R
authors.initials: DR
authors.lastname: Van Wagoner
authors.forename: Eugene
authors.initials: E
authors.lastname: Jung
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Fukamachi
mesh_terms: D000465:Algorithms; D000818:Animals; D017776:Autonomic Pathways; D001794:Blood Pressure; D057785:Catheters; D004285:Dogs; D004558:Electric Stimulation / Q000295:instrumentation* / Q000379:methods; D005260:Female; D006321:Heart / Q000294:innervation* / Q000503:physiopathology; D006339:Heart Rate; D006439:Hemodynamics; D008839:Microelectrodes; D009200:Myocardial Contraction; D010275:Parasympathetic Nervous System; D013564:Sympathetic Nervous System; D016277:Ventricular Function, Left