title: Acute and long-term outcome of transvenous cryothermal catheter ablation of supraventricular arrhythmias involving the perinodal region.
abstract: OBJECTIVE
  Cryoenergy is a new valuable treatment option to perform ablation close to the atrioventricular (AV) node in the cure of supraventricular tachycardias because of its favourable properties, such as the possibility of creating reversible lesions. The aim of this study was to report our experience on the effectiveness and safety of catheter cryoablation performed in "critical areas" to treat a large cohort of patients with supraventricular arrhythmias.
  
  
  METHODS
  One hundred and thirty-one patients suffering from supraventricular tachycardias underwent catheter cryoablation using a 7F catheter. Eighty-seven patients presented with AV nodal re-entrant tachycardia (AVNRT), 39 had accessory pathways (APs) either manifest or concealed (15 midseptal, 24 parahissian), three had ectopic right atrial tachycardia (AT), and two patients had a permanent junctional reciprocating tachycardia (PJRT). When the optimal parameters were recorded, ice mapping at -30 degrees C was performed for 80 s to validate the ablation site. If the expected result occurred, cryoablation was carried out by lowering the temperature to -75 degrees C for 4 min.
  
  
  RESULTS
  In two patients cryoablation was not performed because of technical reasons. Cryoablation was acutely successful in 84 out of 85 patients with AVNRT, in 37 of 39 with APs and in all patients with AT and PJRT. No complications occurred in any patient. Transient AV conduction impairment occurred in seven patients with midseptal APs and in two patients with AVNRT. In particular, in these patients no late permanent AV block was observed at follow-up. At a mean follow-up of 27 +/- 12.9 months, clinical success rate was 87%.
  
  
  CONCLUSIONS
  Cryoablation is a safe and effective technique with a high success rate in the long term. It may be particularly useful when performing ablation close to the AV node or His bundle owing to the possibility of validating the ablation site with ice mapping, which creates only a reversible lesion, mainly in the midseptal APs.
authors.affiliation: Division of Cardiology, Cardinal Massaia Hospital, Asti, Italy. gaitaf@libero.it
authors.forename: Fiorenzo
authors.initials: F
authors.lastname: Gaita
authors.forename: Antonio
authors.initials: A
authors.lastname: Montefusco
authors.forename: Riccardo
authors.initials: R
authors.lastname: Riccardi
authors.forename: Marco
authors.initials: M
authors.lastname: Scaglione
authors.forename: Stefano
authors.initials: S
authors.lastname: Grossi
authors.forename: Domenico
authors.initials: D
authors.lastname: Caponi
authors.forename: Enrico
authors.initials: E
authors.lastname: Caruzzo
authors.forename: Carla
authors.initials: C
authors.lastname: Giustetto
authors.forename: Mario
authors.initials: M
authors.lastname: Bocchiardo
authors.forename: Paolo
authors.initials: P
authors.lastname: Di Donna
mesh_terms: D000293:Adolescent; D000328:Adult; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods*; D015331:Cohort Studies; D003452:Cryosurgery / Q000009:adverse effects / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D005471:Fluoroscopy; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery*; D006346:Heart Septum / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012107:Research Design; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000503:physiopathology / Q000601:surgery; D013614:Tachycardia, Paroxysmal / Q000503:physiopathology / Q000601:surgery; D013617:Tachycardia, Supraventricular / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome