title: Clinical anatomy of the atrioventricular node artery.
abstract: OBJECTIVE
  The study aim was to describe the topographical relationship of the atrioventricular (AV) node artery and mitral valve annulus fibrosus with regard to AV node dysfunction following mitral valve replacement or ring annuloplasty.
  
  
  METHODS
  The anatomy of the AV node artery was analyzed in 55 human hearts without previous pathological alterations. Selective coronary angiograms were performed to identify the AV node origin. Run-off of the AV node artery and its topographical relationship to the mitral valve attachment was analyzed in dry-dissected hearts. The position of the AV node was verified by histological sectioning.
  
  
  RESULTS
  The AV node artery originated from the right coronary artery in 73% of examined cases, and from the left coronary artery in 27% of cases. The left AV node artery was closely related to the mitral valve attachment, especially at the area of the left proximal part of the posterior leaflet.
  
  
  CONCLUSIONS
  These morphological data were compared to clinical reports emphasizing the postoperative incidence of AV block after mitral valve implantation and ring annuloplasty. The occurrence of early postoperative AV node block ranged from 20% to 37%. By comparing the present data with available literature, it can be stated that there is a high risk of intraoperative damage to the left AV node artery during manipulation of the mitral valve annulus fibrosus.
authors.affiliation: University Hospital Zurich, Department of Cardiovascular Surgery, Zurich, Switzerland. denis.berdajs@usz.ch
authors.forename: Denis
authors.initials: D
authors.lastname: Berdajs
authors.forename: Andreas
authors.initials: A
authors.lastname: Künzli
authors.forename: Ulrich
authors.initials: U
authors.lastname: Shurr
authors.forename: Gregor
authors.initials: G
authors.lastname: Zünd
authors.forename: Marko I
authors.initials: MI
authors.lastname: Turina
authors.forename: Michele
authors.initials: M
authors.lastname: Genonni
mesh_terms: D000328:Adult; D000368:Aged; D001283:Atrioventricular Node / Q000033:anatomy & histology*; D002102:Cadaver; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000033:anatomy & histology*; D006352:Heart Ventricles / Q000033:anatomy & histology; D006801:Humans; D066298:In Vitro Techniques; D008875:Middle Aged; D008943:Mitral Valve / Q000033:anatomy & histology