title: Efficacy of catheter ablation for atrial fibrillation in hypertrophic cardiomyopathy: impact of age, atrial remodelling, and disease progression.
abstract: OBJECTIVE
  In patients with hypertrophic cardiomyopathy (HCM) and atrial fibrillation (AF), radiofrequency catheter ablation (RFCA) represents a promising option. However, the predictors of RFCA efficacy remain largely unknown. We assessed the outcome of a multicentre HCM cohort following RFCA for symptomatic AF refractory to medical therapy.
  
  
  RESULTS
  Sixty-one patients (age 54 +/- 13 years; time from AF onset 5.7 +/- 5.5 years) with paroxysmal (n = 35; 57%), recent persistent (n = 15; 25%), or long-standing persistent AF (n = 11; 18%) were enrolled. A scheme with pulmonary vein isolation plus linear lesions was employed. Of the 61 patients, 32 (52%) required redo procedures. Antiarrhythmic therapy was maintained in 22 (54%). At the end of a 29 +/- 16 months follow-up, 41 patients (67%) were in sinus rhythm, including 17 of the 19 patients aged < or = 50 years, with marked improvement in New York Heart Association (NYHA) functional class (1.2 +/- 0.5 vs. 1.9 +/- 0.7 at baseline; P < 0.001). In the remaining 20 patients (33%), with AF recurrence, there was less marked, but still significant, improvement following RFCA (NYHA class 1.8 +/- 0.7 vs. 2.3 +/- 0.7 at baseline; P = 0.002). Independent predictors of AF recurrence were increased left atrium volume [hazard ratio (HR) per unit increase 1.009, 95% confidence interval (CI) 1.001-1.018; P = 0.037] and NYHA functional class (HR 2.24, 95% CI 1.16-4.35; P = 0.016). Among 11 genotyped HCM patients (6 with MYBPC3, 2 with MYH7, 1 with MYL2 and 2 with multiple mutations), RFCA success rate was comparable with that of the overall cohort (n = 8; 73%).
  
  
  CONCLUSIONS
  RFCA was successful in restoring long-term sinus rhythm and improving symptomatic status in most HCM patients with refractory AF, including the subset with proven sarcomere gene mutations, although redo procedures were often necessary. Younger HCM patients with small atrial size and mild symptoms proved to be the best RFCA candidates, likely due to lesser degrees of atrial remodelling.
authors.affiliation: Division of Cardiology, Cardinal Massaia Hospital of Asti and Faculty of Medicine, University of Turin, Corso Dante, 202, Asti 14100, Italy. didonna@asl.at.it
authors.forename: Paolo
authors.initials: P
authors.lastname: Di Donna
authors.forename: Iacopo
authors.initials: I
authors.lastname: Olivotto
authors.forename: Sara Dalila Luisella
authors.initials: SD
authors.lastname: Delcrè
authors.forename: Domenico
authors.initials: D
authors.lastname: Caponi
authors.forename: Marco
authors.initials: M
authors.lastname: Scaglione
authors.forename: Isabelle
authors.initials: I
authors.lastname: Nault
authors.forename: Antonio
authors.initials: A
authors.lastname: Montefusco
authors.forename: Francesca
authors.initials: F
authors.lastname: Girolami
authors.forename: Franco
authors.initials: F
authors.lastname: Cecchi
authors.forename: Michel
authors.initials: M
authors.lastname: Haissaguerre
authors.forename: Fiorenzo
authors.initials: F
authors.lastname: Gaita
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000150:complications* / Q000188:drug therapy / Q000601:surgery*; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000000981:diagnostic imaging / Q000235:genetics; D017115:Catheter Ablation; D003131:Combined Modality Therapy; D018450:Disease Progression; D015150:Echocardiography, Doppler; D005260:Female; D005500:Follow-Up Studies; D005820:Genetic Testing; D005838:Genotype; D006325:Heart Atria / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents