title: Coronary sinus-ventricular accessory connections producing posteroseptal and left posterior accessory pathways: incidence and electrophysiological identification.
abstract: BACKGROUND
  The coronary sinus (CS) has a myocardial coat (CSMC) with extensive connections to the left and right atria. We postulated that some posteroseptal and left posterior accessory pathways (CSAPs) result from connections between a cuff of CSMC extending along the middle cardiac vein (MCV) or posterior coronary vein (PCV) and the ventricle. The purpose of the present study was to use CS angiography and mapping to define and determine the incidence of CSAPs and determine the relationship to CS anatomy.
  
  
  RESULTS
  CSAP was defined by accessory pathway (AP) potential or earliest activation in the MCV or PCV and late activation at anular endocardial sites. A CSAP was identified in 171 of 480 patients undergoing ablation of a posteroseptal or left posterior AP. CS angiography revealed a CS diverticulum in 36 (21%) and fusiform or bulbous enlargement of the small cardiac vein, MCV, or CS in 15 (9%) patients. The remaining 120 (70%) patients had an angiographically normal CS. A CSMC extension potential (CSE), like an AP potential, was recorded in the MCV in 98 (82%), in the PCV in 13 (11%), in both the MCV and PCV in 6 (5%), and in the CS in 3 (2%) of 120 patients. CSMC potentials were recorded between the timing of atrial and CSE potentials.
  
  
  CONCLUSIONS
  CSAPs result from a connection between a CSMC extension (along the MCV or PCV) and the ventricle. The CS is angiographically normal in most patients.
authors.affiliation: Cardiac Arrhythmia Research Institute and Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City 73104, USA.
authors.forename: Yingxian
authors.initials: Y
authors.lastname: Sun
authors.forename: Mauricio
authors.initials: M
authors.lastname: Arruda
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Otomo
authors.forename: Karen
authors.initials: K
authors.lastname: Beckman
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakagawa
authors.forename: James
authors.initials: J
authors.lastname: Calame
authors.forename: Sunny
authors.initials: S
authors.lastname: Po
authors.forename: Peter
authors.initials: P
authors.lastname: Spector
authors.forename: Daniel
authors.initials: D
authors.lastname: Lustgarten
authors.forename: Lisa
authors.initials: L
authors.lastname: Herring
authors.forename: Ralph
authors.initials: R
authors.lastname: Lazzara
authors.forename: Warren
authors.initials: W
authors.lastname: Jackman
mesh_terms: D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000503:physiopathology*; D018780:Body Surface Potential Mapping; D017023:Coronary Angiography; D003330:Coronary Vessel Anomalies / Q000000981:diagnostic imaging / Q000503:physiopathology; D003331:Coronary Vessels / Q000033:anatomy & histology / Q000503:physiopathology*; D004240:Diverticulum / Q000000981:diagnostic imaging / Q000503:physiopathology; D006329:Heart Conduction System / Q000503:physiopathology*; D006346:Heart Septum; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D008955:Models, Cardiovascular