title: Myocardial Microvascular Responsiveness During Acute Cardiac Sympathectomy Induced by Thoracic Epidural Anesthesia.
abstract: OBJECTIVE
  To evaluate the effect of acute cardiac sympathectomy by thoracic epidural anesthesia on myocardial blood flow and microvascular function.
  
  
  METHODS
  A prospective observational study.
  
  
  METHODS
  The study was conducted in a tertiary teaching hospital.
  
  
  METHODS
  Ten patients with a mean age of 48 years (range 22-63 years) scheduled for thoracic surgery.
  
  
  METHODS
  Myocardial contrast echocardiography was used to study myocardial blood flow and microvascular responsiveness at rest, during adenosine-induced hyperemia, and after sympathetic stimulation by the cold pressor test. Repeated measurements were performed without and with thoracic epidural anesthesia.
  
  
  RESULTS
  An increased myocardial blood volume was observed with thoracic epidural anesthesia compared to baseline (from 0.08±0.02 to 0.10±0.03 mL/mL; p = 0.02). No difference existed in resting myocardial blood flow between baseline conditions and epidural anesthesia (0.85±0.24 v 1.03±0.27 mL/min/g, respectively). Hyperemia during thoracic epidural anesthesia increased myocardial blood flow to 4.31±1.07 mL/min/g (p = 0.0008 v baseline) and blood volume to 0.17±0.04 mL/mL (p = 0.005 baseline). After sympathetic stimulation, no difference in myocardial blood flow parameters was observed CONCLUSIONS: Acute cardiac sympathectomy by thoracic epidural anesthesia increased the blood volume in the myocardial capillary system. Also, thoracic epidural anesthesia increased hyperemic myocardial blood flow, indicating augmented endothelial-independent vasodilator capacity of the myocardium.
authors: Department of Anesthesiology, VU University Medical Center, MB Amsterdam, The Netherlands. Electronic address: c.bulte@vumc.nl.
authors: Carolien S E
authors: CS
authors: Bulte
authors: Department of Anesthesiology, VU University Medical Center, MB Amsterdam, The Netherlands.
authors: Christa
authors: C
authors: Boer
authors: Department of Surgery, VU University Medical Center, MB Amsterdam, The Netherlands.
authors: Koen J
authors: KJ
authors: Hartemink
authors: Department of Cardiology, VU University Medical Center, MB Amsterdam, The Netherlands.
authors: Otto
authors: O
authors: Kamp
authors: Epidemiology and Biostatistics, VU University Medical Center, MB Amsterdam, The Netherlands.
authors: Martijn W
authors: MW
authors: Heymans
authors: Department of Anesthesiology, VU University Medical Center, MB Amsterdam, The Netherlands.
authors: Stephen A
authors: SA
authors: Loer
authors: Department of Cardiology, Bern University Hospital, Bern, Switzerland.
authors: Stefano F
authors: SF
authors: de Marchi
authors: Department of Cardiology, Bürgerspital Solothurn, Solothurn, Switzerland.
authors: Rolf
authors: R
authors: Vogel
authors: Department of Anesthesiology, VU University Medical Center, MB Amsterdam, The Netherlands.
authors: R Arthur
authors: RA
authors: Bouwman
mesh_terms: D000328:Adult; D000767:Anesthesia, Epidural / Q000379:methods*; D001340:Autonomic Nerve Block / Q000379:methods; D003326:Coronary Circulation / Q000502:physiology; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004452:Echocardiography; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000502:physiology; D008875:Middle Aged; D011446:Prospective Studies; D013562:Sympathectomy / Q000379:methods*; D013904:Thoracic Vertebrae; D014664:Vasodilation / Q000502:physiology; D055815:Young Adult
keywords: cardiac sympathectomy; myocardial blood flow; thoracic epidural anesthesia