title: Contractile reserve and extent of transmural necrosis in the setting of myocardial stunning: comparison at cardiac MR imaging.
abstract: OBJECTIVE
  To perform a comparison of cardiac magnetic resonance (MR) imaging-derived ejection fraction (EF) during low-dose dobutamine infusion (EF(D)) with the extent of segments with transmural necrosis in more than 50% of their wall thickness (ETN) for the prediction of major adverse cardiac events (MACEs) and late systolic recovery soon after a first ST-segment elevation myocardial infarction (STEMI).
  
  
  METHODS
  Institutional ethics committee approval and written informed consent were obtained. One hundred nineteen consecutive patients with a first STEMI, a depressed left ventricular EF, and an open infarct-related artery underwent MR imaging at 1 week after infarction. EF(D) and ETN (by using a 17-segment model) were determined, and the prediction of MACEs and systolic recovery at follow-up was assessed by using area under the receiver operating characteristic curve (AUC) and multivariable regression analysis.
  
  
  RESULTS
  During follow-up (median, 613 days; range, 312-1243 days), 18 MACEs (five cardiac deaths, six myocardial infarctions, seven readmissions for heart failure) occurred. MACEs were associated with a lower EF(D) (43% +/- 12 [standard deviation] vs 49% +/- 10, P = .02) and a larger ETN (seven segments +/- three vs four segments +/- three, P < .001). Patients with systolic recovery (increase in EF of >5% at follow-up compared with baseline EF, n = 44) displayed a higher EF(D) (51% +/- 10 vs 47% +/- 9, P = .04) and a smaller ETN (three segments +/- two vs five segments +/- three, P = .002) at 1 week. ETN and EF(D) both related to MACEs (AUC: 0.78 vs 0.67, respectively, P = .1) and systolic recovery (AUC: 0.68 vs 0.62, respectively, P = .3). According to multivariable analysis, ETN was the only MR variable associated with time to MACEs (hazard ratio, 1.38; 95% confidence interval: 1.19, 1.60; P < .001) and systolic recovery (odds ratio, 0.76; 95% confidence interval: 0.64, 0.92; P = .004) independent of baseline characteristics.
  
  
  CONCLUSIONS
  ETN is as useful as EF(D) for the prediction of MACEs and systolic recovery soon after STEMI.
authors.affiliation: Hospital Clínico Universitario, INCLIVA, Universidad de Valencia, Blasco Ibáñez 17, 46010 Valencia, Spain. vicentbodi@hotmail.com
authors.forename: Vicente
authors.initials: V
authors.lastname: Bodí
authors.forename: Oliver
authors.initials: O
authors.lastname: Husser
authors.forename: Juan
authors.initials: J
authors.lastname: Sanchis
authors.forename: Julio
authors.initials: J
authors.lastname: Núñez
authors.forename: María P
authors.initials: MP
authors.lastname: López-Lereu
authors.forename: José V
authors.initials: JV
authors.lastname: Monmeneu
authors.forename: Luis
authors.initials: L
authors.lastname: Mainar
authors.forename: Fabian
authors.initials: F
authors.lastname: Chaustre
authors.forename: Günter A J
authors.initials: GA
authors.lastname: Riegger
authors.forename: María J
authors.initials: MJ
authors.lastname: Bosch
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Chorro
authors.forename: Angel
authors.initials: A
authors.lastname: Llácer
mesh_terms: D017130:Angioplasty; D019540:Area Under Curve; D006328:Cardiac Catheterization; D002316:Cardiotonic Agents / Q000008:administration & dosage; D016009:Chi-Square Distribution; D003287:Contrast Media; D004280:Dobutamine / Q000008:administration & dosage; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D009203:Myocardial Infarction / Q000473:pathology* / Q000503:physiopathology / Q000628:therapy; D017682:Myocardial Stunning / Q000473:pathology* / Q000503:physiopathology / Q000628:therapy; D009336:Necrosis; D011446:Prospective Studies; D012044:Regression Analysis; D019233:Retreatment; D015607:Stents
chemical_list: D002316:Cardiotonic Agents; D003287:Contrast Media; D004280:Dobutamine; D019786:Gadolinium DTPA