title: The impact of cryoballoon-based catheter ablation on left atrial structural and potential electrical remodeling in patients with paroxysmal atrial fibrillation.
abstract: BACKGROUND
  While atrial fibrillation (AF) begets AF via structural, contractile, and electrical remodeling, it was shown that successful radiofrequency ablation of AF has effectively reversed left atrial (LA) remodeling. However, there was little data regarding the efficacy of cryoablation on LA remodeling. Herein, we aimed to assess the impact of cryoablation on LA structural and potential electrical remodeling in paroxysmal AF patients.
  
  
  METHODS
  A total of 41 symptomatic patients with non-valvular paroxysmal AF underwent their first catheter ablation via cryoballoon technique. All patients had transthoracic echocardiography before, 6 and 12 months after cryoablation. LA volume index (LAVI), left intra-, right intra-, and inter-atrial electromechanical conduction delay (AEMD) were calculated in all patients. Postprocedural first 3 months was accepted as blanking period.
  
  
  RESULTS
  All 179 pulmonary veins were isolated successfully in 41 patients with no major complication. During median 18 months (12-20 months) follow-up, recurrent atrial arrhythmia was found in nine patients (21.9%). In multivariate Cox regression analysis, only early recurrence was found as the independent predictor of late recurrence. At 12th month visit compared to baseline, there was no change in LAVI (p = 0.647) but significant increase in left intra- and inter-AEMD (p < 0.05). However, in non-recurrent group, both LAVI (30.63 ± 3.6 to 28.42 ± 3.63, p < 0.001), left intra-AEMD (18.75 ± 8.77 to 12.5 ± 4.65, p < 0.001), and inter-AEMD (25.2 ± 13.2 to 18.84 ± 8.52, p < 0.001) were significantly decreased.
  
  
  CONCLUSIONS
  Our study findings revealed that successful cryoballoon-based AF ablation yields LA structural and potential electrical reverse remodeling. However, LA remodeling process cannot be halted by cryoablation in patients with AF recurrence during follow-up.
authors.affiliation: Department of Cardiology, Hacettepe University Faculty of Medicine, Ankara, Turkey. dru_canpolat@yahoo.com.
authors.forename: Uğur
authors.initials: U
authors.lastname: Canpolat
authors.affiliation: Department of Cardiology, Hacettepe University Faculty of Medicine, Ankara, Turkey.
authors.forename: Kudret
authors.initials: K
authors.lastname: Aytemir
authors.affiliation: Department of Cardiology, Hacettepe University Faculty of Medicine, Ankara, Turkey.
authors.forename: Necla
authors.initials: N
authors.lastname: Özer
authors.affiliation: Department of Cardiology, Hacettepe University Faculty of Medicine, Ankara, Turkey.
authors.forename: Ali
authors.initials: A
authors.lastname: Oto
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D064752:Atrial Remodeling; D017115:Catheter Ablation / Q000379:methods*; D003452:Cryosurgery / Q000379:methods*; D056966:Excitation Contraction Coupling; D005260:Female; D006325:Heart Atria / Q000503:physiopathology*; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
keywords: Atrial fibrillation; Atrial remodeling; Cryoablation; Echocardiography