Multislice computed tomography and magnetic resonance imaging for the assessment of reperfused acute myocardial infarction.
OBJECTIVE
We evaluated the accuracy of in vivo delayed-enhancement multislice computed tomography (DE-MSCT) and delayed-enhancement magnetic resonance imaging (DE-MRI) for the assessment of myocardial infarct size using postmortem triphenyltetrazolium chloride (TTC) pathology as standard of reference.


BACKGROUND
The diagnostic value of DE-MSCT for the assessment of acute reperfused myocardial infarction is currently unclear.


METHODS
In 10 domestic pigs (25 to 30 kg), the circumflex coronary artery was balloon-occluded for 2 h followed by reperfusion. After 5 days (3 to 7 days), DE-MRI (1.5-T) was performed 15 min after administration of 0.2 mmol/kg gadolinium-DTPA using an inversion recovery gradient echo technique. On the same day, DE-MSCT (64-slice) was performed 15 min after administration of 1 gI/kg of iodinated contrast material. One day after imaging, hearts were excised, sectioned in 8 mm short-axis slices, and stained with TTC. Infarct size was defined as the hyperenhanced area on DE-MSCT and DE-MRI images and the TTC-negative area on TTC pathology slices. Infarct size was expressed as percentage of total slice area.


RESULTS
Infarct size determined by DE-MSCT and DE-MRI showed a good correlation with infarct size assessed with TTC pathology (R2 = 0.96 [p < 0.001] and R(2) = 0.93 [p < 0.001], respectively). The correlation between DE-MSCT and DE-MRI was also good (R2 = 0.96; p < 0.001). The relative difference in CT attenuation value of infarcted myocardium compared to remote myocardium was 191 +/- 18%. The relative MR signal intensity between infarcted myocardium and remote myocardium was 554 +/- 156%.


CONCLUSIONS
We demonstrated that DE-MSCT can assess acute reperfused myocardial infarction in good agreement with in vivo DE-MRI and TTC pathology.
Baks
Timo
T
Department of Cardiology, Thoraxcenter, Erasmus University Medical Center, Rotterdam, The Netherlands.
Cademartiri
Filippo
F
Moelker
Amber D
AD
Weustink
Annick C
AC
van Geuns
Robert-Jan
RJ
Mollet
Nico R
NR
Krestin
Gabriel P
GP
Duncker
Dirk J
DJ
de Feyter
Pim J
PJ
D000818:Animals; D004396:Coloring Agents; D003287:Contrast Media; D019786:Gadolinium DTPA; D007479:Iopamidol / Q000031:analogs & derivatives*; D008279:Magnetic Resonance Imaging / Q000379:methods; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000473:pathology; D013552:Swine; D013778:Tetrazolium Salts; D014057:Tomography, X-Ray Computed / Q000379:methods
D004396:Coloring Agents; D003287:Contrast Media; D013778:Tetrazolium Salts; C057937:iomeprol; C009591:triphenyltetrazolium; D007479:Iopamidol; D019786:Gadolinium DTPA