title: Relationship between infarct size and severity measured by gated SPECT and long-term left ventricular remodelling after acute myocardial infarction.
abstract: OBJECTIVE
  After acute myocardial infarction (AMI), left ventricular (LV) remodelling may occur despite successful reperfusion. This study aimed to investigate by gated single photon emission computed tomography (SPECT) the long-term evolution of myocardial perfusion and LV function after AMI and to identify the predictors of LV remodelling.
  
  
  METHODS
  Sixty-eight AMI patients successfully treated by primary percutaneous coronary intervention underwent (99m)Tc-sestamibi gated SPECT at 1 month (baseline) and over 6-month follow-up after the acute event. LV remodelling was defined as 20% increase in LV end-diastolic volume at follow-up.
  
  
  RESULTS
  At baseline, patients with remodelling (n = 14) showed larger (infarct size 29.3 ± 7.8%) and more transmural (infarct severity 0.28 ± 0.10) infarctions, and reduced LV ejection fraction (35.4 ± 5.6%), but similar LV volume indexes, compared to patients without remodelling (n = 54) (infarct size 20.8 ± 14.4%, p < 0.05, infarct severity 0.40 ± 0.11, p < 0.001, ejection fraction 44.5 ± 9.2, p < 0.001). At stepwise multivariate regression analysis, infarct severity showed the best predictive value for predicting LV remodelling (F = 5.54, p < 0.05). Using the thresholds identified by receiver-operating characteristic curve analysis, infarct size and severity detected patients with remodelling with 75% accuracy and 95% negative predictive value. Infarct resorption (defined as the defect size difference between follow-up and baseline) was comparable between patients with (-4.4 ± 8.4%) and without remodelling (-6.8 ± 9.4%) (p = NS).
  
  
  CONCLUSIONS
  Perfusion parameters assessed by gated SPECT in the subacute phase after successfully treated AMI correlate with changes in functional parameters at long-term follow-up. Infarct severity is more effective than infarct size, but both are helpful for predicting LV remodelling.
authors.affiliation: Nuclear Medicine Unit, Department of Clinical Physiopathology, University of Florence, Florence, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Berti
authors.forename: Roberto
authors.initials: R
authors.lastname: Sciagrà
authors.forename: Wanda
authors.initials: W
authors.lastname: Acampa
authors.forename: Francesca
authors.initials: F
authors.lastname: Ricci
authors.forename: Giampaolo
authors.initials: G
authors.lastname: Cerisano
authors.forename: Rosj
authors.initials: R
authors.lastname: Gallicchio
authors.forename: Carlo
authors.initials: C
authors.lastname: Vigorito
authors.forename: Alberto
authors.initials: A
authors.lastname: Pupi
authors.forename: Alberto
authors.initials: A
authors.lastname: Cuocolo
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D055426:Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; D003326:Coronary Circulation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology*; D012189:Retrospective Studies; D013997:Time Factors; D020257:Ventricular Remodeling