title: Frequency and predictors of tachycardia-induced cardiomyopathy in patients with persistent atrial flutter.
abstract: BACKGROUND
  There are few data on the frequency and predictors of tachycardia-induced cardiomyopathy (TICM) in patients with persistent atrial flutter.
  
  
  OBJECTIVE
  To examine the incidence of TICM in patients undergoing ablation for persistent atrial flutter, and to examine predictors for the development of TICM.
  
  
  RESULTS
  One hundred eleven patients met the inclusion criteria for the present study. Twenty-eight of 111 (25%) patients had cardiomyopathy before ablation. Sixteen of 28 (57%) patients showed significant improvement in their left ventricular (LV) function postablation. LV function improved to normal in 12 of 16 (75%) patients. Nineteen of 28 (68%) cardiomyopathy patients had preablation LV function in the range in which they would be considered for an implantable cardioverter defibrillator for primary prevention of sudden cardiac death. In nine of 19 (47%) patients, the ejection fraction improved such that an implantable cardioverter defibrillator was no longer indicated. In multivariate analysis, average ventricular rate during atrial flutter was the only independent predictor of reversibility of cardiomyopathy (P=0.013).
  
  
  CONCLUSIONS
  Sixteen of 28 (57%) cardiomyopathy patients with persistent atrial flutter had significantly improved LV function postablation. In 75% of these patients, LV function improved to normal.
authors: University of Ottawa Heart Institute, Ottawa, Ontario, Canada.
authors: Stephen
authors: S
authors: Pizzale
authors: Robert
authors: R
authors: Lemery
authors: Martin S
authors: MS
authors: Green
authors: Michael H
authors: MH
authors: Gollob
authors: Anthony S L
authors: AS
authors: Tang
authors: David H
authors: DH
authors: Birnie
mesh_terms: D000368:Aged; D001282:Atrial Flutter / Q000150:complications* / Q000601:surgery; D009202:Cardiomyopathies / Q000453:epidemiology* / Q000209:etiology; D017115:Catheter Ablation; D005260:Female; D005544:Forecasting; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013610:Tachycardia / Q000150:complications*; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000209:etiology