title: Ethanol infusion in the vein of Marshall leads to parasympathetic denervation of the human left atrium: implications for atrial fibrillation.
abstract: OBJECTIVE
  This study sought to determine whether ethanol infusion in the vein of Marshall (VOM) can ablate intrinsic cardiac nerves (ICN).
  
  
  BACKGROUND
  ICN cluster around the left atrial epicardium and are implicated in the genesis of atrial fibrillation (AF).
  
  
  METHODS
  Patients undergoing catheter AF ablation underwent adjunctive ethanol injection in the VOM. A multipolar catheter was introduced in the VOM and used for high-frequency stimulation (HFS), either as HFS with P-wave synchronized (SynchHFS), 30 pulses, 100 Hz (n = 8) or as HFS with 3 to 10 s bursts (BurstHFS), 33 Hz (n = 72) at 25 mA for 1-ms duration. Atrioventricular (AV) nodal conduction slowing (asystole >2 s or R-R interval prolongation >50%) and AF inducibility were assessed before and after VOM ethanol infusion. Up to 4 1-ml infusions of 98% ethanol were delivered via an angioplasty balloon in the VOM.
  
  
  RESULTS
  SynchHFS induced AF in 8 of 8 patients. In 4 of 8 AF initiated spontaneously without VOM capture. No parasympathetic responses were elicited by SynchHFS. BurstHFS was performed in 32 patients undergoing de novo AF ablation (Group 1) and 40 patients undergoing repeat ablation (Group 2). Parasympathetic responses were found in all 32 Group 1 patients and in 75% of Group 2 patients. After VOM ethanol infusion, parasympathetic responses were abolished in all patients (both groups). There were no acute complications related to VOM ethanol infusion.
  
  
  CONCLUSIONS
  The VOM contains ICN that connect with the AV node and can trigger AF. Retrograde ethanol infusion in the VOM reliably eliminates local ICN responses. The VOM is a vascular route for ICN-targeting therapies.
authors.affiliation: Methodist DeBakey Heart and Vascular Center and Methodist Hospital Research Institute, The Methodist Hospital, Houston, Texas.
authors.forename: José L
authors.initials: JL
authors.lastname: Báez-Escudero
authors.affiliation: Department of Cardiology, Edogawa Hospital, Tokyo, Japan.
authors.forename: Takehiko
authors.initials: T
authors.lastname: Keida
authors.affiliation: Methodist DeBakey Heart and Vascular Center and Methodist Hospital Research Institute, The Methodist Hospital, Houston, Texas.
authors.forename: Amish S
authors.initials: AS
authors.lastname: Dave
authors.affiliation: Yokohama-City Bay Red Cross Hospital, Yokohama, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Okishige
authors.affiliation: Methodist DeBakey Heart and Vascular Center and Methodist Hospital Research Institute, The Methodist Hospital, Houston, Texas. Electronic address: mvalderrabano@houstonmethodist.org.
authors.forename: Miguel
authors.initials: M
authors.lastname: Valderrábano
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology / Q000628:therapy*; D017115:Catheter Ablation / Q000379:methods; D003331:Coronary Vessels / Q000187:drug effects / Q000294:innervation* / Q000601:surgery; D000431:Ethanol / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000187:drug effects / Q000294:innervation* / Q000601:surgery; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D017764:Parasympathectomy / Q000379:methods*
chemical_list: D000431:Ethanol
keywords: atrial fibrillation; ethanol; intrinsic cardiac nerves; vein of Marshall