title: Relevance of Conduction Disorders in Bachmann's Bundle During Sinus Rhythm in Humans.
abstract: BACKGROUND
  Bachmann's bundle (BB) is considered to be the main route of interatrial conduction and to play a role in development of atrial fibrillation (AF). The goals of this study are to characterize the presence of conduction disorders in BB during sinus rhythm and to study their relation with AF.
  
  
  RESULTS
  High-resolution epicardial mapping (192 unipolar electrodes, interelectrode distance: 2 mm) of sinus rhythm was performed in 185 patients during coronary artery bypass surgery of whom 13 had a history of paroxysmal AF. Continuous rhythm monitoring was used to detect postoperative AF during the first 5 postoperative days. In 67% of the patients, BB was activated from right to left; in the remaining patients from right and middle (21%), right, central, and left (8%), or central (4%) site. Mean effective conduction velocity was 89 cm/s. Conduction block was present in most patients (75%; median 1.1%, range 0-12.8) and was higher in patients with paroxysmal AF compared with patients without a history of AF (3.2% versus 0.9%; P=0.03). A high amount of conduction block (>4%) was associated with de novo postoperative AF (P=0.02). Longitudinal lines of conduction block >10 mm were also associated with postoperative AF (P=0.04).
  
  
  CONCLUSIONS
  BB may be activated through multiple directions, but the predominant route of conduction is from right to left. Conduction velocity across BB is around 90 cm/s. Conduction is blocked in both longitudinal and transverse direction in the majority of patients. Conduction disorders, particularly long lines of longitudinal conduction block, are more pronounced in patients with AF episodes.
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Christophe P
authors.initials: CP
authors.lastname: Teuwen
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Ameeta
authors.initials: A
authors.lastname: Yaksh
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Eva A H
authors.initials: EA
authors.lastname: Lanters
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Charles
authors.initials: C
authors.lastname: Kik
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Lisette J M E
authors.initials: LJ
authors.lastname: van der Does
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Paul
authors.initials: P
authors.lastname: Knops
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Yannick J H J
authors.initials: YJ
authors.lastname: Taverne
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Pieter C
authors.initials: PC
authors.lastname: van de Woestijne
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Frans B S
authors.initials: FB
authors.lastname: Oei
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Jos A
authors.initials: JA
authors.lastname: Bekkers
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Ad J J C
authors.initials: AJ
authors.lastname: Bogers
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.).
authors.forename: Maurits A
authors.initials: MA
authors.lastname: Allessie
authors.affiliation: From the Deparment of Cardiology (C.P.T., A.Y., E.A.H.L., L.J.M.E.v.d.D., P.K., M.A.A., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (C.K., Y.J.H.J.T., P.C.v.d.W., F.B.S.O., J.A.B., A.J.J.C.B.), Erasmus University Medical Center, Rotterdam; and Department of Physiology, Cardiovascular Research Institute, Maastricht, The Netherlands (M.A.A.). n.m.s.degroot@erasmusmc.nl.
authors.forename: Natasja M S
authors.initials: NM
authors.lastname: de Groot
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology*; D002036:Bundle of His / Q000503:physiopathology*; D004567:Electrodes, Implanted; D056149:Epicardial Mapping / Q000295:instrumentation*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D013614:Tachycardia, Paroxysmal / Q000175:diagnosis / Q000503:physiopathology*
keywords: Bachmann’s bundle; atrial fibrillation; electrophysiology; mapping; sinus rhythm