Currently, little is known regarding the value of quantitative parameters derived from the intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) with integrated slice-specific shimming (iShim) sequence in detecting old
myocardial infarction and myocardial
fibrosis. This study was to investigate the value of IVIM-MRI with iShim sequence in diagnosing old
myocardial infarction and
fibrosis. Thirty-five patients with both old
myocardial infarction and myocardial
fibrosis and 12 healthy volunteers were prospectively enrolled to undergo cardiac diffusion-weighted imaging (DWI) using seven b-values (0, 20, 60, 80, 120, 200 and 600 s/mm2). The iShim sequence was used for IVIM data acquisition, and the diffusion parameters,
D, D* and f values for IVIM, and conventional apparent diffusion coefficient (ADC) were evaluated on the anterior, posterior and lateral walls of the ventricular septum using the short axis of the heart. Significant differences were found in the
D, D* and f values between healthy subjects and patients with old
myocardial infarction and myocardial
fibrosis (P = 0.000), with the median value of the D and f significantly smaller in the
myocardial infarction and
fibrosis than in the normal control but the median value of D* significantly greater in the
myocardial infarction and
fibrosis than in the normal control. In the receiver operating curve analysis, the areas under the curve were 0.939, 0.988 and 0.959 for the
D, D* and f values, respectively. The sensitivities and specificities were 84.6% and 94.4% for D, 88.9% and 84.6% for D* and 100% and 93.1% for the f values, respectively. In conclusion, the IVIM-derived parameters (
D, D* and f) obtained using the iShim DWI technique showed high capacity in diagnosing old
myocardial infarction and myocardial
fibrosis by providing diffusion and perfusion information, which may have great importance in future clinical practice.