title: Sestamibi single photon emission computed tomography immediately after primary percutaneous coronary intervention identifies patients at risk for large infarcts.
abstract: BACKGROUND
  Primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction results in TIMI 3 flow in most patients. However, despite TIMI 3 flow, some patients do not achieve adequate tissue perfusion and have large infarctions. Techniques that, in the acute setting, could identify these patients at increased risk would potentially enable specific interventions to enhance perfusion. The object of the present study was to test whether corrected TIMI frame count (CTFC), myocardial blush grade (MBG), ST-segment resolution, and myocardial perfusion imaging (MPI) can identify those patients who, despite successful treatment with primary PCI for ST-elevation myocardial infarction, are at risk for large infarcts.
  
  
  METHODS
  In 61 patients with TIMI 3 flow after primary PCI, CTFC, MBG, ST-segment resolution, and quantitative MPI by technetium Tc 99m sestamibi single photon emission computed tomography were estimated immediately after primary PCI. Infarct size was assessed by peak lactate dehydrogenase (LDH) and by MPI after 3 months.
  
  
  RESULTS
  Infarct size by MPI was 12% (4, 23), and peak LDH was 1410 U/L (870, 2220); these measures correlated (rho = 0.80, P < .001). The acute perfusion defect predicted infarct size using either method (MPI rho = 0.88, P < .001; LDH rho = 0.77, P < .001); ST-segment residual correlated weakly to infarct size, whereas CTFC and MBG did not. In multivariate analysis, the acute perfusion defect was the only significant predictor of infarct size.
  
  
  CONCLUSIONS
  Myocardial perfusion imaging performed immediately after successful PCI can identify patients at increased risk for large infarcts due to impaired tissue perfusion. Acute MPI might serve as a tool for early identification of patients, who, despite epicardial TIMI 3 flow, have inadequate tissue level perfusion.
authors.affiliation: Department of Cardiology, Aarhus University Hospital, Skejby, Denmark.
authors.forename: Anne
authors.initials: A
authors.lastname: Kaltoft
authors.forename: Morten
authors.initials: M
authors.lastname: Bøttcher
authors.forename: Niels Peter
authors.initials: NP
authors.lastname: Sand
authors.forename: Michael
authors.initials: M
authors.lastname: Rehling
authors.forename: Niels Trolle
authors.initials: NT
authors.lastname: Andersen
authors.forename: Felix
authors.initials: F
authors.lastname: Zijlstra
authors.forename: Torsten Toftegaard
authors.initials: TT
authors.lastname: Nielsen
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D017023:Coronary Angiography; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy*; D015425:Myocardial Reperfusion; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012008:Recurrence; D012307:Risk Factors; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi