title: Tachycardia-related cardiomyopathy: a common cause of ventricular dysfunction in patients with atrial fibrillation referred for atrioventricular ablation.
abstract: OBJECTIVE
  To determine the frequency of tachycardia-related cardiomyopathy in patients with atrial fibrillation and systolic dysfunction referred for atrioventricular node ablation.
  
  
  METHODS
  This prospective multicenter cohort study was conducted at 16 tertiary care centers. The ejection fraction was measured before and 3 and 12 months after atrioventricular node ablation. Patients with reduced systolic function (ejection fraction < or = 45%) before atrioventricular ablation were included in this study. Patients whose ejection fraction increased by at least 15 percentage points and to higher than 45% were considered to have tachycardia-related cardiomyopathy.
  
  
  RESULTS
  Of 63 patients with systolic dysfunction, 48 had at least 1 adequate follow-up echocardiographic study. Sixteen (25%) of the 63 had marked improvement in the ejection fraction (mean +/- SD change, 27 +/- 8 percentage points) to a value higher than 45% after ablation.
  
  
  CONCLUSIONS
  Tachycardia-related cardiomyopathy is common in patients with atrial fibrillation and systolic dysfunction referred for atrioventricular node ablation. This diagnosis should be considered in all patients in whom systolic dysfunction occurs subsequent to or concomitant with onset of atrial fibrillation.
authors.affiliation: Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: M M
authors.initials: MM
authors.lastname: Redfield
authors.forename: G N
authors.initials: GN
authors.lastname: Kay
authors.forename: L S
authors.initials: LS
authors.lastname: Jenkins
authors.forename: M
authors.initials: M
authors.lastname: Mianulli
authors.forename: D N
authors.initials: DN
authors.lastname: Jensen
authors.forename: K A
authors.initials: KA
authors.lastname: Ellenbogen
mesh_terms: D001281:Atrial Fibrillation / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy; D001283:Atrioventricular Node; D009202:Cardiomyopathies / Q000150:complications* / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D017115:Catheter Ablation; D006801:Humans; D011446:Prospective Studies; D012042:Registries; D013318:Stroke Volume; D013599:Systole; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology