title: Catheter ablation of atriofascicular Mahaim fibers guided by the activation potential.
abstract: OBJECTIVE
  To determine whether recording of the activation potential may be used as an isolated criterion to guide catheter ablation of atriofascicular Mahaim fibers.
  
  
  METHODS
  We studied 6 patients (5 females, mean age of 26 +/- 7.3 years) with paroxysmal tachycardias with a wide QRS complex, whose electrophysiological study diagnosed atriofascicular Mahaim fibers. Mapping and catheter ablation were performed in sinus rhythm, guided only by the recording of the activation potential of the fiber.
  
  
  RESULTS
  Efficacy in ablation was achieved in all patients. The fibers were located in the right lateral region of the tricuspid ring in 3 patients, right posterolateral region in 2, and right anterolateral region in 1. A mean of 5.3 +/- 3 radiofrequency applications was performed. The mean fluoroscopy time was 46.6 +/- 25 minutes, and the mean duration of the procedure was 178.6 +/- 108 minutes. No complication occurred. In a mean 20-month follow-up, all patients were asymptomatic and receiving no antiarrhythmic drugs.
  
  
  CONCLUSIONS
  Catheter ablation of Mahaim fibers may be performed with good safety and efficacy by mapping the activation potential of the tricuspid ring in sinus rhythm.
authors.affiliation: Hospital Universitário Cajuru, PUC/PR, Brazil. masilve@sulbbs.com.br
authors.forename: Márcio Augusto
authors.initials: MA
authors.lastname: Silva
authors.forename: Gel
authors.initials: G
authors.lastname: Berardi
authors.forename: Alessandro
authors.initials: A
authors.lastname: Kraemer
authors.forename: Elenir
authors.initials: E
authors.lastname: Nadalin
authors.forename: José Carlos Moura
authors.initials: JC
authors.lastname: Jorge
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000293:Adolescent; D000328:Adult; D001283:Atrioventricular Node / Q000502:physiology*; D017115:Catheter Ablation; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D011227:Pre-Excitation, Mahaim-Type / Q000503:physiopathology / Q000601:surgery*; D013614:Tachycardia, Paroxysmal / Q000503:physiopathology / Q000601:surgery*