In myocarditis, cardiac magnetic resonance imaging (MRI) provides diagnostic and prognostic insights by assessing the presence of myocarditis lesions on late gadolinium enhancement (LGE) sequences and evaluating left ventricular ejection fraction (LVEF). The balanced steady‐state free precession (b‐SSFP) sequence is commonly used to assess LVEF. Recently, b‐SSFP after gadolinium‐based contrast injection (b‐SSFP‐Gd) has been integrated into cardiac MRI protocols. We hypothesized that b‐SSFP‐Gd enhances the MRI protocol for acute viral myocarditis diagnosis by improving lesion detection and reducing examination time. This study simultaneously evaluated the performance of b‐SSFP‐Gd for the detection of acute viral myocarditis lesions compared with the LGE sequence and for LVEF measurement compared with the b‐SSFP sequence.

This retrospective single‐center study included 38 patients with strong evidence of acute viral myocarditis. The 17‐Segment American Heart Association classification was used to compare the number of affected segments on LGE and b‐SSFP‐Gd. Diagnostic performance was assessed using sensitivity, specificity, and area under the curve analysis. LVEF was measured in 30 patients using b‐SSFP and b‐SSFP‐Gd. The results were statistically analyzed using Pearson's correlation, paired t‐tests, and intraclass correlation coefficients.

The sensitivity and specificity of b‐SSFP‐Gd were 100.0% (95% confidence interval: 90.8%–100.0%) and 100.0% (95% confidence interval: 91.2%–100.0%), respectively, with an area under the curve of 1.000 for lesion detection. The number of segments measured on LGE sections correlated with the number of segments measured on b‐SSFP‐Gd in diastole (r[36] = 0.83, p < 0.001) and systole (r[36] = 0.78, p < 0.001). There was no statistically significant difference in LVEF between b‐SSFP and b‐SSFP‐Gd (p = 0.34).

b‐SSFP‐Gd more accurately detected myocarditis lesions than the LGE sequence and was as effective as the b‐SSFP sequence for LVEF calculation. b‐SSFP‐Gd could be integrated into cardiac MRI protocols to aid in the diagnosis of acute myocarditis, along with the LGE sequence, while reducing the overall examination time by replacing b‐SSFP for LVEF measurement.

Cardiac magnetic resonance imaging (MRI) plays a key role in assessing acute myocardial infarction (AMI) and detecting myocardial edema. Diffusion‐weighted imaging (DWI) has recently been applied to cardiac exploration and is perceived as a promising method for evaluating cardiomyopathies. This study aims to evaluate the role of DWI in the assessment of AMI by analyzing the accuracy of both low b‐value diffusion‐weighted (DW) spin‐echo (SE) echo‐planar imaging (EPI) sequence and apparent diffusion coefficient (ADC) mapping in detecting ischemia‐induced myocardial edema.

This study included 13 patients with recent reperfused AMI who underwent cardiac MRI. A cardiac protocol was applied, including black blood T2‐weighted imaging (BB‐T2W), two low b‐value DW SE EPI (b = 20 s/mm²), one for low b‐value DW SE EPI in free‐breathing (DWF) and the other for low b‐value DW SE EPI in breath‐holding (DWH), T2 mapping, and ADC mapping. BB‐T2W, DWH, and DWF images were analyzed quantitatively and qualitatively. The T2 and ADC values were measured within the infarct and remote myocardium. Statistical analysis was performed using a nonparametric Wilcoxon test.

ADC values in the infarct area were significantly higher than the remote myocardium ([2.36 ± 0.34] × 10⁻³ mm²/s and [1.20 ± 0.14] × 10⁻³ mm²/s, respectively; p = 0.001). Besides, low b‐value DW SE EPI (DWH and DWF) allowed the detection of ischemia‐induced myocardial edema in a way surpassing the BB‐T2W sequence with a higher sensitivity to edema (96.7%, 96.7%, and 87.9%, respectively). No statistically significant difference was noted between DWH and DWF sequences.

DWI may be a promising technique for the exploration of AMI, with the advantage of being feasible for dyspneic patients.