title: Adenosine-sensitive bundle branch reentry.
abstract: BACKGROUND
  Bundle branch reentry is an uncommon mechanism for ventricular tachycardia. More infrequently, both fascicles of the left bundle may provide the substrate for such macroreentrant bundle branch circuits, so-called interfascicular reentry. The effect of adenosine on bundle branch reentrant mechanisms of tachycardia is unknown.
  
  
  RESULTS
  A 59-year-old man with no apparent structural heart disease and history of frequent symptomatic wide complex tachycardias was referred to our center for further electrophysiologic evaluation. During electrophysiologic study, a similar tachycardia was reproducibly initiated only during isoproterenol infusion, which had the characteristics of bundle branch reentry, possibly using a left interfascicular mechanism. Intravenous adenosine reproducibly terminated the tachycardia. Application of radiofrequency energy to the breakout site from the left posterior fascicle prevented subsequent tachycardia induction and rendered the patient free of spontaneous tachycardia during long-term follow-up.
  
  
  CONCLUSIONS
  Patients with ventricular tachycardia involving a bundle branch reentrant circuit may be sensitive to adenosine. These results suggest that adenosine may not only inhibit catecholamine-mediated triggered activity but also some catecholamine-mediated reentrant ventricular arrhythmias.
authors.affiliation: Electrophysiology Laboratory, University of Chicago Hospitals, IL 60637, USA.
authors.forename: D S
authors.initials: DS
authors.lastname: Rubenstein
authors.forename: M C
authors.initials: MC
authors.lastname: Burke
authors.forename: J G
authors.initials: JG
authors.lastname: Kall
authors.forename: C A
authors.initials: CA
authors.lastname: Kinder
authors.forename: D E
authors.initials: DE
authors.lastname: Kopp
authors.forename: D J
authors.initials: DJ
authors.lastname: Wilber
mesh_terms: D000241:Adenosine / Q000008:administration & dosage*; D000284:Administration, Oral; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage*; D002037:Bundle-Branch Block; D004562:Electrocardiography; D006801:Humans; D008297:Male; D013610:Tachycardia / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology
chemical_list: D000889:Anti-Arrhythmia Agents; D000241:Adenosine