Assessment of myocardial viability in reperfused acute myocardial infarction using 16-slice computed tomography in comparison to magnetic resonance imaging

Abstract

Objectives: The aim of this study was to examine if contrast-enhanced multislice spiral computed tomography (MSCT) is comparable to contrast-enhanced magnetic resonance imaging (MRI) for depiction of acute myocardial infarction (MI).

Background: Delayed-enhancement MRI of MI is well established, but there are no clinical reports about MSCT for this indication. Early perfusion deficit on MSCT has been reported to correlate with the presence of MI.

Methods: A total of 28 consecutive patients (23 men; 55.9 +/- 11.4 years) with reperfused MI underwent contrast-enhanced cardiac 16-slice MSCT. Images were acquired in the arterial phase and the late phase 15 min after administration of 120 ml contrast material. Within 5 days, patients underwent MRI after administration of 0.2 mmol Gd-dimeglumine/kg/bodyweight. All examinations were completed within two weeks after MI. The area of MI was compared between the different imaging techniques using Bland-Altman method and multivariate analysis. Agreement of the contrast enhancement patterns was evaluated with a weighted kappa test.

Results: Mean infarct size on MRI was 31.2 +/- 22.5% per slice compared with 33.3 +/- 23.8% per slice for late-enhancement MSCT and 24.5 +/- 18.3% per slice for early-perfusion-deficit MSCT. Bland-Altman data showed a good agreement between late-enhancement MRI and late-enhancement MSCT. Contrast enhancement patterns demonstrated an excellent agreement between late-enhancement MRI and late-enhancement MSCT (kappa = 0.878). The results were worse comparing MRI and early-phase MSCT (kappa = 0.635).

Conclusions: Multislice spiral computed tomography allows for the assessment of acute MI. Late-enhancement MSCT appears to be as reliable as delayed contrast-enhanced MRI in assessing infarct size and myocardial viability in acute MI.