title: Global left ventricular longitudinal systolic strain for early risk assessment in patients with acute myocardial infarction treated with primary percutaneous intervention.
abstract: BACKGROUND
  Left ventricular systolic function is a key determinant of outcome after ST-segment elevation myocardial infarction (STEMI). The aim of this study was to study speckle-tracking global longitudinal strain (GLS) for early risk evaluation in STEMI and compare it with left ventricular ejection fraction (LVEF), wall motion score index (WMSI), and end-systolic volume index (ESVI).
  
  
  METHODS
  Five-hundred seventy-six patients underwent echocardiography ≤24 hours after primary percutaneous coronary intervention for STEMI. The end point was the composite of death, hospitalization with reinfarction, congestive heart failure, or stroke. Associations with outcome were assessed by multivariate Cox regression with adjustment for clinical parameters. Hazard ratios (HRs) for events within the first year are reported per absolute percentage GLS increase.
  
  
  RESULTS
  During a median follow-up period of 24 months, 162 patients experienced at least one event. GLS was associated with the composite end point (adjusted HR, 1.20; 95% confidence interval [CI], 1.12-1.29) and also when controlling for LVEF (adjusted HR, 1.17; 95% CI, 1.07-1.29) and ESVI (adjusted HR, 1.18; 95% CI, 1.08-1.28). Although WMSI was significantly associated with outcome beyond any association accounted for by GLS, a borderline significant association was found after controlling for WMSI (adjusted HR for GLS, 1.10; 95% CI, 1.00-1.21). When GLS or WMSI was known, there was no significant association between LVEF or ESVI and outcome.
  
  
  CONCLUSIONS
  In a large population of patients with STEMI, GLS and WMSI were comparable and both superior for early risk assessment compared with volume-based left ventricular function indicators such as LVEF and ESVI. Compared with WMSI, the advantage of GLS is the provision of a semiautomated quantitative measure.
authors.affiliation: Department of Cardiology, Aarhus University Hospital Skejby, Aarhus, Denmark. kim.munk@ki.au.dk
authors.forename: Kim
authors.initials: K
authors.lastname: Munk
authors.forename: Niels H
authors.initials: NH
authors.lastname: Andersen
authors.forename: Christian J
authors.initials: CJ
authors.lastname: Terkelsen
authors.forename: Bo M
authors.initials: BM
authors.lastname: Bibby
authors.forename: Søren P
authors.initials: SP
authors.lastname: Johnsen
authors.forename: Hans E
authors.initials: HE
authors.lastname: Bøtker
authors.forename: Torsten T
authors.initials: TT
authors.lastname: Nielsen
authors.forename: Steen H
authors.initials: SH
authors.lastname: Poulsen
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000706:statistics & numerical data*; D015897:Comorbidity; D003718:Denmark; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D015995:Prevalence; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery