title: Concealed Accessory Pathways with a Single Ventricular and Two Discrete Atrial Insertion Sites.
abstract: BACKGROUND
  Atrioventricular reciprocating tachycardia (AVRT) utilizing a concealed accessory pathway is common. It is well appreciated that some patients may have multiple accessory pathways with separate atrial and ventricular insertion sites.
  
  
  METHODS
  We present three cases of AVRT utilizing concealed pathways with evidence that each utilizing a single ventricular insertion and two discrete atrial insertion sites.
  
  
  RESULTS
  In case one, two discrete atrial insertion sites were mapped in two separate procedures, and only during the second ablation was the Kent potential identified. Ablation of the Kent potential at this site remote from the two atrial insertion sites resulted in the termination of the retrograde conduction in both pathways. Case two presented with supraventricular tachycardia (SVT) with alternating eccentric atrial activation patterns without alteration in the tachycardia cycle length. The two distinct atrial insertion sites during orthodromic AVRT and ventricular pacing were targeted and each of the two atrial insertion sites were successfully mapped and ablated. In case three, retrograde decremental conduction utilizing both atrial insertion sites was identified prior to ablation. After mapping and ablation of the first discrete atrial insertion site, tachycardia persisted utilizing the second atrial insertion site. Only after ablation of the second atrial insertion site was SVT noninducible, and VA conduction was no longer present.
  
  
  CONCLUSIONS
  Concealed retrograde accessory pathways with discrete atrial insertion sites may have a common ventricular insertion site. Identification and ablation of the ventricular insertion site or the separate discrete atrial insertion sites result in successful treatment.
authors.affiliation: Division of Cardiology, Section of Electrophysiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin.
authors.forename: Ryan T
authors.initials: RT
authors.lastname: Kipp
authors.affiliation: Cardiac Pacing and Electrophysiology, University of Ottawa Heart Institute, Ottawa, Ontario, Canada.
authors.forename: Raed
authors.initials: R
authors.lastname: Abu Sham'a
authors.affiliation: Division of Cardiology, Section of Electrophysiology, University of California, San Francisco, California.
authors.forename: Ito
authors.initials: I
authors.lastname: Hiroyuki
authors.affiliation: Division of Cardiovascular Medicine, Section of Electrophysiology, University of Utah, Salt Lake City, Utah.
authors.forename: Frederick T
authors.initials: FT
authors.lastname: Han
authors.affiliation: Department of Internal Medicine, Cardiovascular Medicine/Cardiac Electrophysiology, American University of Beirut Faculty of Medicine and Medical Center, Beirut, Lebanon.
authors.forename: Marwan
authors.initials: M
authors.lastname: Refaat
authors.affiliation: Division of Cardiology, Section of Electrophysiology, University of California, San Diego, California.
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Hsu
authors.affiliation: Division of Cardiology, Section of Electrophysiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Field
authors.affiliation: Division of Cardiology, Section of Electrophysiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin.
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Kopp
authors.affiliation: Division of Cardiology, Section of Electrophysiology, University of California, San Francisco, California.
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Marcus
authors.affiliation: Division of Cardiology, Section of Electrophysiology, University of California, San Francisco, California.
authors.forename: Melvin M
authors.initials: MM
authors.lastname: Scheinman
authors.affiliation: Division of Cardiology, Section of Electrophysiology, University of California, San Diego, California.|Division of Cardiology, Section of Electrophysiology, VA San Diego Healthcare System, San Diego, California.
authors.forename: Kurt S
authors.initials: KS
authors.lastname: Hoffmayer
mesh_terms: D058606:Accessory Atrioventricular Bundle / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology*; D000328:Adult; D018780:Body Surface Potential Mapping / Q000379:methods; D003937:Diagnosis, Differential; D005260:Female; D006325:Heart Atria / Q000294:innervation / Q000503:physiopathology*; D006352:Heart Ventricles / Q000294:innervation / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology*
keywords: ablation; accessory pathways; catheter