title: Echocardiographic left atrial reverse remodeling after catheter ablation of atrial fibrillation is predicted by preablation delayed enhancement of left atrium by magnetic resonance imaging.
abstract: BACKGROUND
  Atrial fibrosis is a hallmark of atrial structural remodeling (SRM) and leads to structural and functional impairment of left atrial (LA) and persistence of atrial fibrillation (AF). This study was conducted to assess LA reverse remodeling after catheter ablation of AF in mild and moderate-severe LA SRM.
  
  
  METHODS
  Catheter ablation was performed in 68 patients (age 62 ± 14 years, 68% males) with paroxysmal (n = 26) and persistent (n = 42) AF. The patients were divided into group 1 with mild LA SRM (<10%, n = 31) and group 2 with moderate-severe LA SRM (>10%, n = 37) by delayed enhancement magnetic resonance imaging (DEMRI). Two-dimensional echocardiography, LA strain, and strain rate during left ventricular systole by velocity vector imaging were performed pre and at 6 ± 3 months postablation. The long-term outcome was monitored for 12 months.
  
  
  RESULTS
  Patients in group 1 were younger (57 ± 15 vs 66 ± 13 years, P = .009) with a male predominance (80% vs 57%, P < .05) as compared to group 2. Postablation, group 1 had significant increase in average LA strain (Δ↑: 14% vs 4%, P < .05) and strain rate (Δ↑: 0.5 vs 0.1 cm/s, P < .05) as compared to group 2. There was a trend toward more patients with persistent AF in group 2 (68% vs 55%, P = .2), but it was not statistically significant. Group 2 had more AF recurrences (41% vs 16%, P = .02) at 12 months after ablation.
  
  
  CONCLUSIONS
  Mild preablation LA SRM by DEMRI predicts favorable LA structural and functional reverse remodeling and long-term success after catheter ablation of AF, irrespective of the paroxysmal or persistent nature of AF.
authors.affiliation: Division of Cardiology, University of Utah, Salt Lake City, UT, USA. suman.kuppahally@hsc.utah.edu
authors.forename: Suman S
authors.initials: SS
authors.lastname: Kuppahally
authors.forename: Nazem
authors.initials: N
authors.lastname: Akoum
authors.forename: Troy J
authors.initials: TJ
authors.lastname: Badger
authors.forename: Nathan S
authors.initials: NS
authors.lastname: Burgon
authors.forename: Thomas
authors.initials: T
authors.lastname: Haslam
authors.forename: Eugene
authors.initials: E
authors.lastname: Kholmovski
authors.forename: Rob
authors.initials: R
authors.lastname: Macleod
authors.forename: Christopher
authors.initials: C
authors.lastname: McGann
authors.forename: Nassir F
authors.initials: NF
authors.lastname: Marrouche
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D016279:Atrial Function, Left / Q000502:physiology*; D017115:Catheter Ablation / Q000379:methods*; D003430:Cross-Sectional Studies; D018618:Echocardiography, Doppler, Color / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods; D011379:Prognosis; D011446:Prospective Studies; D012720:Severity of Illness Index; D020257:Ventricular Remodeling / Q000502:physiology*