title: Safety and efficacy of cryoablation of atrial tachycardia with high risk of ablation-related injuries.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the safety and efficacy of cryoablation as an alternative to radio frequency (RF) ablation in high-risk-located atrial tachycardia (AT).
  
  
  RESULTS
  Between 2004 and 2007, 164 patients underwent catheter ablation due to AT at our institution. Twenty-six of these patients (22 women and 4 men), median age 58 years (range 14-76), were considered having high-risk-located AT and were treated by cryoablation. Seven patients had failed prior RF ablation due to high risk of complications. The AT foci distribution was: close to the AV node (n = 14), vicinity of the sinus node (n = 7), and crista terminalis adjacent to the phrenic nerve (n = 5). Cryomapping, using a 6 mm tip catheter, at -30 degrees C was performed before ablation with a goal temperature of -80 degrees C for 240 s. Acute success rate was achieved in 25/26 patients (96%). During a follow-up of 493 +/- 258 days, three patients had recurrences. Two of these underwent a second successful cryoablation procedure. Long-term success rate was 92%. Phrenic nerve palsy occurred in two patients with complete recovery after 1 day and 5 months, respectively.
  
  
  CONCLUSIONS
  Cryoablation of high-risk-located AT foci is a safe and effective alternative to RF therapy.
authors.affiliation: Department of Cardiology, Karolinska Institute, Karolinska University Hospital, S-141 86 Stockholm, Sweden. hamid.bastani@karolinska.se
authors.forename: Hamid
authors.initials: H
authors.lastname: Bastani
authors.forename: Per
authors.initials: P
authors.lastname: Insulander
authors.forename: Jonas
authors.initials: J
authors.lastname: Schwieler
authors.forename: Fariborz
authors.initials: F
authors.lastname: Tabrizi
authors.forename: Frieder
authors.initials: F
authors.lastname: Braunschweig
authors.forename: Göran
authors.initials: G
authors.lastname: Kennebäck
authors.forename: Nikola
authors.initials: N
authors.lastname: Drca
authors.forename: Bita
authors.initials: B
authors.lastname: Sadigh
authors.forename: Mats
authors.initials: M
authors.lastname: Jensen-Urstad
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001283:Atrioventricular Node / Q000503:physiopathology*; D003452:Cryosurgery / Q000009:adverse effects* / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010791:Phrenic Nerve / Q000293:injuries*; D012307:Risk Factors; D012849:Sinoatrial Node / Q000503:physiopathology*; D013612:Tachycardia, Ectopic Atrial / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult