title: Prediction of sudden cardiac death in patients after acute myocardial infarction using T-wave alternans: a prospective study.
abstract: OBJECTIVE
  We assessed the value of T-wave alternans (TWA) in prediction of sudden cardiac death (SCD) in patients with acute myocardial infarction (AMI).
  
  
  METHODS
  Consecutive patients (N = 227) were enrolled and were monitored with 24-hour ambulatory electrocardiogram within 1 to 15 days after AMI. T-wave alternans was identified by a modified moving average (MMA) algorithm computer software. The primary end point was SCD or lethal ventricular arrhythmia. We analyzed the hazard ratios (HRs) using the previously determined 47 μV TWA cutpoint.
  
  
  RESULTS
  During the 16 ± 7-month follow-up, 10 (4.4%) patients died suddenly. T-wave alternans (≥47 μV) predicted SCD (HR, 17.78 [95% confidence interval, 3.75-84.31]; P < .0001). Moreover, patients with 5 or more TWA episodes (≥47 μV) were at higher risk for SCD (HR, 20.75 [95% confidence interval, 5.77-74.57]; P < .0001).
  
  
  CONCLUSIONS
  T-wave alternans (≥47 μV) monitored at 1 to 15 days after AMI-predicted heightened risk of SCD. Prediction is improved when the frequency of TWA episodes (≥47 μV) is analyzed.
authors.affiliation: Clinical Electrophysiology Laboratory and Arrhythmia Center, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Xicheng State, Beijing, China.
authors.forename: Hou
authors.initials: H
authors.lastname: Yu
authors.forename: Fang
authors.initials: F
authors.lastname: Pi-Hua
authors.forename: Wu
authors.initials: W
authors.lastname: Yuan
authors.forename: Li
authors.initials: L
authors.lastname: Xiao-Feng
authors.forename: Liu
authors.initials: L
authors.lastname: Jun
authors.forename: Li
authors.initials: L
authors.lastname: Zhi
authors.forename: Lei
authors.initials: L
authors.lastname: Sen
authors.forename: Shu
authors.initials: S
authors.lastname: Zhang
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000503:physiopathology*; D016009:Chi-Square Distribution; D016757:Death, Sudden, Cardiac; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology*; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D015996:Survival Rate