title: Cryoablation of junctional tachycardia at high risk of atrio-ventricular block.
abstract: BACKGROUND
  Transcatheter cryoablation is an alternative option for the treatment of supraventricular tachycardia, due to its very low risk of permanent atrio-ventricular block. However, the overcost of cryocatheter and the high recurrence rate of this emerging technology braked its large use. This study reports the results of an approach using cryoablation for the treatment of junctional tachycardia (JT) in selected patients at high risk of atrio-ventricular (AV) block.
  
  
  METHODS
  Out of a series of 199 patients with JT treated by catheter ablation, 26 benefited from cryoablation (mean age 32.8+/-15 years, 15 males). The indications were the presence of an accessory pathway with a high risk of atrio-ventricular block (n=7), a slow pathway difficult to ablate, with a risk of atrio-ventricular block (n=7), a recurrence after a RF procedure, during which a transient atrio-ventricular block has occurred (n=4), and finally patients at young age (n=8).
  
  
  RESULTS
  The primary success rate was 92%. No permanent AV block has been reported, neither with RF nor with cryoablation. The recurrence rate at 9+/-10 months was at 29% after cryoablation and 8.6% after RF. In case of AV nodal reentrant tachycardia, the additional cost of cryotherapy catheter has been avoided in 76.85% of cases. The use of a cryotherapy catheter and RF catheter has been necessary for the remaining cases.
  
  
  CONCLUSIONS
  This study demonstrates that an approach, reserving cryoablation in selected patients at high risk of AV block is an alternative strategy to "the systematic use" of cryotherapy in the ablation of JT with a high efficacy, an excellent safety and a reduced cost.
authors.affiliation: Service de cardiologie, Centre hospitalier universitaire d'Amiens-Picardie, Avenue René-Laennec, Amiens cedex. nadji.georges@free.fr
authors.forename: G
authors.initials: G
authors.lastname: Nadji
authors.forename: J-S
authors.initials: JS
authors.lastname: Hermida
authors.forename: M
authors.initials: M
authors.lastname: Kubala
authors.forename: S
authors.initials: S
authors.lastname: Quenum
authors.forename: H
authors.initials: H
authors.lastname: Bakkour
authors.forename: G
authors.initials: G
authors.lastname: Jarry
mesh_terms: D000328:Adult; D054537:Atrioventricular Block / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D001283:Atrioventricular Node / Q000503:physiopathology / Q000601:surgery*; D006328:Cardiac Catheterization; D003452:Cryosurgery / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013613:Tachycardia, Ectopic Junctional / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome