title: Early prediction of myocardial viability after acute myocardial infarction by two-dimensional speckle tracking imaging.
abstract: BACKGROUND
  Identifying the transmural extent of myocardial necrosis and the degree of myocardial viability in acute myocardial infarction (AMI) is important clinically. The aim of this study was to assess myocardial viability using two-dimensional speckle tracking imaging (2D-STI) in patients with AMI.
  
  
  METHODS
  2D-STI was performed at initial presentation, three days, and six months after primary percutaneous coronary intervention (PCI) in 30 patients with AMI, who had a left anterior descending coronary artery (LAD) culprit lesion. In addition, 20 patients who had minimal stenotic lesions (< 30% stenosis) on coronary angiography were also included in the control group. At six months dobutamine echocardiography was performed for viability assessment in seven segments of the LAD territory. According to the recovery of wall motion abnormality, segments were classified as viable or non-viable.
  
  
  RESULTS
  A total of 131 segments were viable, and 44 were nonviable. Multivariate analysis revealed significant differences between the viable and nonviable segments in the peak systolic strain, the peak systolic strain rate at initial presentation, and peak systolic strain rate three days after primary PCI. Among these, the initial peak systolic strain rate had the highest predictive value for myocardial viability (hazard ratio: 31.22, P < 0.01).
  
  
  CONCLUSIONS
  2D-STI is feasible for assessing myocardial viability, and the peak systolic strain rate might be the most reliable predictor of myocardial viability in patients with AMI.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University, Seoul, South Korea.
authors.forename: Jong Shin
authors.initials: JS
authors.lastname: Woo
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University, Seoul, South Korea.
authors.forename: Tae-Kyung
authors.initials: TK
authors.lastname: Yu
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University, Seoul, South Korea.
authors.forename: Woo-Shik
authors.initials: WS
authors.lastname: Kim
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University, Seoul, South Korea.
authors.forename: Kwon Sam
authors.initials: KS
authors.lastname: Kim
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University, Seoul, South Korea.
authors.forename: Weon
authors.initials: W
authors.lastname: Kim
keywords: Acute myocardial infarction; Two-dimensional speckle tracking imaging; Viable myocardium