title: Predictors of atrial fibrillation in hypertrophic cardiomyopathy.
abstract: Atrial fibrillation (AF) is associated with increased morbidity and mortality in patients with hypertrophic cardiomyopathy (HCM). The primary aim of this study (HCM Risk-AF) was to determine the predictors of AF in a large multicentre cohort of patients with HCM. Exploratory analyses were performed to investigate the association between AF and survival and the efficacy of antiarrhythmic therapy in maintaining sinus rhythm (SR).
  
  
  
  A retrospective, longitudinal cohort of patients recruited between 1986 and 2008 in seven centres was used to develop multivariable Cox regression models fitted with preselected predictors. HCM was defined as unexplained hypertrophy (maximum left ventricular wall thickness of ≥15 mm or in accordance with published criteria for the diagnosis of familial disease). 28% of patients (n=1171) had coexistent hypertension. The primary end point was paroxysmal, permanent or persistent AF detected on ECG, Holter monitoring or implantable device interrogation.
  
  
  
  Of the 4248 patients with HCM without pre-existing AF, 740 (17.4%) reached the primary end point. Multivariable Cox regression revealed an association between AF and female sex, age, left atrial diameter, New York Heart Association (NYHA) class, hypertension and vascular disease. The proportion of patients with cardiovascular death at 10 years was 4.9% in the SR group and 10.9% in the AF group (difference in proportions=5.9%; 95% CI (4.1% to 7.8%)). The proportion of patients with non-cardiovascular death at 10 years was 3.2% in the SR group and 5.9% in the AF group (difference in proportions=2.8%; 95% CI (0.1% to 4.2%)). An intention-to-treat propensity score analysis demonstrated that β-blockers, calcium channel antagonists and disopyramide initially maintained SR during follow-up, but their protective effect diminished with time. Amiodarone therapy did not prevent AF during follow-up.
  
  
  
  This study shows that patients with HCM who are at risk of AF development can be identified using readily available clinical parameters. The development of AF is associated with a poor prognosis but there was no evidence that antiarrhythmic therapy prevents AF in the long term.
authors: University College London Institute for Cardiovascular Science and Barts Heart Centre, St. Bartholomew's Hospital, London, UK.
authors: Oliver P
authors: OP
authors: Guttmann
authors: Department of Statistical Science, University College London, London, UK.
authors: Menelaos
authors: M
authors: Pavlou
authors: University College London Institute for Cardiovascular Science and Barts Heart Centre, St. Bartholomew's Hospital, London, UK.
authors: Constantinos
authors: C
authors: O'Mahony
authors: Cardiology Department and Research Unit, A Coruña University Hospital, Galician Health Service, Spain.
authors: Lorenzo
authors: L
authors: Monserrat
authors: Unit of Inherited Cardiovascular Diseases, First Department of Cardiology, University of Athens, Athens, Greece.
authors: Aristides
authors: A
authors: Anastasakis
authors: Department of Specialised, Experimental and Diagnostic Medicine, Institute of Cardiology, University of Bologna, Bologna, Italy.
authors: Claudio
authors: C
authors: Rapezzi
authors: Department of Specialised, Experimental and Diagnostic Medicine, Institute of Cardiology, University of Bologna, Bologna, Italy.
authors: Elena
authors: E
authors: Biagini
authors: Cardiac Department, University Hospital Virgen ArrixacaMurcia, Spain.
authors: Juan Ramon
authors: JR
authors: Gimeno
authors: Monaldi Hospital, Second University of Naples, Naples, Italy.
authors: Giuseppe
authors: G
authors: Limongelli
authors: Heart Failure and Inherited Cardiac Diseases Unit, Hospital Universitario Puerta del Hierro Majadahonda, Madrid, Spain.
authors: Pablo
authors: P
authors: Garcia-Pavia
authors: University College London Institute for Cardiovascular Science and Barts Heart Centre, St. Bartholomew's Hospital, London, UK.
authors: William J
authors: WJ
authors: McKenna
authors: Department of Statistical Science, University College London, London, UK.|Biostatistics Group, University College London Hospitals/University College London Clinical Research Centre, University College London, London, UK.
authors: Rumana Z
authors: RZ
authors: Omar
authors: University College London Institute for Cardiovascular Science and Barts Heart Centre, St. Bartholomew's Hospital, London, UK.
authors: Perry M
authors: 0000-0003-3383-3984
authors: PM
authors: Elliott
mesh_terms: D000200:Action Potentials; D000328:Adult; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000401:mortality / Q000503:physiopathology / Q000517:prevention & control; D002312:Cardiomyopathy, Hypertrophic / Q000188:drug therapy / Q000453:epidemiology* / Q000401:mortality / Q000503:physiopathology; D015716:Electrocardiography, Ambulatory; D005060:Europe / Q000453:epidemiology; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects / Q000503:physiopathology*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D015995:Prevalence; D057216:Propensity Score; D016016:Proportional Hazards Models; D065840:Protective Factors; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents