title: Cryoablation versus radiofrequency ablation for treatment of atrioventricular nodal reentrant tachycardia: cryoablation with 6-mm-tip catheters is still less effective than radiofrequency ablation.
abstract: BACKGROUND
  The treatment of choice for atrioventricular nodal reentrant tachycardia (AVNRT) is catheter ablation of the atrioventricular nodal slow pathway.
  
  
  OBJECTIVE
  The purpose of this study was to ascertain whether cryoablation (Cryo) with 6-mm-tip catheters is as effective as radiofrequency ablation (RF).
  
  
  METHODS
  Patients who had catheter ablation for AVNRT between 2005 and 2008 were identified. The main outcome measure was overall success without the use of an alternative energy source and no recurrence.
  
  
  RESULTS
  Two hundred eighty-eight procedures in 272 patients were identified; 184 were female (68%), and the mean age was 53 +/- 14 (17-88) years. There were 123 Cryo and 149 RF procedures. Cryo had a lower overall success rate (83% vs. 93%; P = .02). Mean procedure times were similar in both groups (90 minutes; P = .5). Fluoroscopy time was longer with Cryo: 16 (7-48) versus 14 (5-50) minutes (P = .04). Only one case of atrioventricular block was observed in the RF group (0.7%). Cryo was more expensive than RF ( pounds sterling 3141 vs. pounds sterling 2153).
  
  
  CONCLUSIONS
  Even when delivering multiple lesions with 6-mm-tip catheters, Cryo is less effective than RF. RF is recommended as a first-line treatment, although the only major complication occurred in the RF group.
authors.affiliation: Heart Rhythm Service, St. Bartholomew's Hospital, London, UK. aaishaopel@aol.com
authors.forename: Aaisha
authors.initials: A
authors.lastname: Opel
authors.forename: Sam
authors.initials: S
authors.lastname: Murray
authors.forename: Nikhil
authors.initials: N
authors.lastname: Kamath
authors.forename: Mehul
authors.initials: M
authors.lastname: Dhinoja
authors.forename: Dominic
authors.initials: D
authors.lastname: Abrams
authors.forename: Simon
authors.initials: S
authors.lastname: Sporton
authors.forename: Richard
authors.initials: R
authors.lastname: Schilling
authors.forename: Mark
authors.initials: M
authors.lastname: Earley
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation; D003452:Cryosurgery / Q000295:instrumentation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000628:therapy*; D016896:Treatment Outcome; D055815:Young Adult