title: Cryotherapy ablation of parahisian accessory pathways in children.
abstract: BACKGROUND
  Because of its safety profile, cryoablation has become an alternative therapy for septal arrhythmias, including parahisian accessory pathways (APs). Data regarding its efficacy, safety, and late outcome for parahisian APs in children are limited.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the safety and efficacy of cryoablation of parahisian APs in children.
  
  
  METHODS
  Fifty-nine cryoablations of parahisian APs were performed in 50 patients [76% males; median age 16.5 years (range 5.3-20 years)]. Thirty-three had manifest APs and 17 had concealed APs. The time to effect was defined as the duration of time from reaching -30°C to the disappearance of AP during the cryomapping phase. The acute success rate for the first ablation was 94% (47/50).
  
  
  RESULTS
  Mean fluoroscopy time and number of cryoablations were 28.5 ± 23.3 minutes and 2.6 ± 1.2 seconds, respectively. The time to effect was 8.5 ± 7.1 seconds. The overall recurrence rate was 14.9%, decreasing from 40% in the first 10 cases to 8.1% in the next 37 (P <.02). Multivariate analysis showed that the only independent predictor for recurrence rate was time to effect <10 seconds (P <.001). A high recurrence rate was also associated with concealed APs and ablation during supraventricular tachycardia (P <.03 and P <.05, respectively). The patients who had recurrence underwent a second successful cryoablation. During median follow-up of 59.7 months (range 6-102 months), a long-term success rate of 94% was achieved. No permanent ablation-related complications occurred.
  
  
  CONCLUSIONS
  Cryoablation of parahisian APs has excellent short- and long-term efficacy and safety profile. Increased physician experience is associated with a reduced recurrence rate.
authors: Kaplan Medical Center, Rehovot, The Hebrew University, Jerusalem, Israel. Electronic address: swissam@mail.huji.ac.il.
authors: Moshe
authors: M
authors: Swissa
authors: Schneider Children's Hospital in Israel, Petach Tikva, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors: Einat
authors: E
authors: Birk
authors: Schneider Children's Hospital in Israel, Petach Tikva, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors: Tamir
authors: T
authors: Dagan
authors: Schneider Children's Hospital in Israel, Petach Tikva, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors: Michal
authors: M
authors: Fogelman
authors: Schneider Children's Hospital in Israel, Petach Tikva, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors: Tom
authors: T
authors: Einbinder
authors: Schneider Children's Hospital in Israel, Petach Tikva, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors: Elchanan
authors: E
authors: Bruckheimer
authors: Sheba Medical Center, Tel Hashomer, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors: Ilan
authors: I
authors: Goldenberg
authors: Sheba Medical Center, Tel Hashomer, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors: Robert
authors: R
authors: Klempfner
authors: Labatt Family Heart Centre and Department of Pediatrics, Hospital for Sick Children and University of Toronto, Toronto, Canada.
authors: Joel A
authors: JA
authors: Kirsh
authors: Schneider Children's Hospital in Israel, Petach Tikva, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors: Rami
authors: R
authors: Fogelman
mesh_terms: D058606:Accessory Atrioventricular Bundle / Q000503:physiopathology / Q000601:surgery*; D000293:Adolescent; D002648:Child; D003452:Cryosurgery / Q000009:adverse effects / Q000379:methods; D004452:Echocardiography / Q000379:methods; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods; D005260:Female; D005471:Fluoroscopy / Q000379:methods; D005500:Follow-Up Studies; D006801:Humans; D007430:Intraoperative Care / Q000379:methods; D007557:Israel; D008297:Male; D061646:Operative Time; D012008:Recurrence; D012189:Retrospective Studies; D016896:Treatment Outcome; D014927:Wolff-Parkinson-White Syndrome / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery
keywords: Cryoablation; Parahisian accessory pathway; Wolff-Parkinson-White syndrome