title: MDCT has the potential to predict percutaneous coronary intervention outcome in swine model: microscopic validation.
abstract: BACKGROUND
  Volumes and sizes of dislodged coronary microemboli vary during PCI so their effects at the left ventricular (LV) and cellular levels cannot be quantified. Furthermore, biopsy for tissue characterization is not an option in PCI patients.
  
  
  OBJECTIVE
  To characterize and validate microinfarct size, LAD territory where microinfarct were found using multidetector computed tomography (MDCT), histochemical staining and microscopy as a function of microemboli volumes and to scale the effects of microemboli volumes on LV function.
  
  
  METHODS
  Under X-ray guidance, a 3F catheter was inserted into LAD coronary artery of 14 pigs for delivering 16 mm(3) or 32 mm(3) of 40-120 μm microemboli. MDCT imaging/histochemical staining/microscopy were performed 3 days later and used to characterize regional and global structural and functional changes in LV by threshold/planimetric methods.
  
  
  RESULTS
  MDCT and ex-vivo methods were able to quantify microinfarct size and LAD territory where microinfarct was found as a function of volumes. However, MDCT and histochemical staining significantly underestimated microinfarct size and territory where microinfarct was found compared with microscopy. MDCT demonstrated the functional changes and showed a moderate correlation between LV ejection fraction and microinfarct size (r = 0.53). Microscopy provided higher spatial resolution for measuring islands of necrotic cells, which explains the difference in measuring structural changes.
  
  
  CONCLUSIONS
  MDCT showed the difference in microinfarct size and LAD territory as a function of microemboli volumes and scaled the changes in LV function. This experimental study gives clinicians a reference for the effects of defined microemboli volumes on myocardial viability and LV function and the under-estimation of microinfarct on MDCT.
authors.affiliation: Interventional Radiology Laboratory, Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA. maythem.saeed@ucsf.edu
authors.forename: Maythem
authors.initials: M
authors.lastname: Saeed
authors.forename: Steven W
authors.initials: SW
authors.lastname: Hetts
authors.forename: Loi
authors.initials: L
authors.lastname: Do
authors.forename: Sammir
authors.initials: S
authors.lastname: Sullivan
authors.forename: Mark W
authors.initials: MW
authors.lastname: Wilson
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D003287:Contrast Media; D017023:Coronary Angiography; D003328:Coronary Thrombosis / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D005471:Fluoroscopy; D007472:Iohexol; D008863:Microspheres; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology / Q000628:therapy*; D011237:Predictive Value of Tests; D011857:Radiographic Image Interpretation, Computer-Assisted; D013552:Swine; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol