Objective: MRI has become the primary tool for assessment of myocardial inflammation in patients with suspected acute myocarditis. Optimal diagnostic performance is achieved with late gadolinium-enhanced sequences, but cine balanced steady-state free precession (SSFP) MRI sequences are routinely used to evaluate cardiac function. Our aim was to prospectively assess the diagnostic value of unenhanced and contrast-enhanced cine SSFP MRI sequences in comparison with late gadolinium-enhanced sequences for imaging of patients with strong evidence of acute myocarditis.
Subjects and methods: Eighteen patients with strong evidence of acute myocarditis underwent 1.5-T cardiac MRI. Unenhanced and contrast-enhanced cine SSFP images and late gadolinium-enhanced images were obtained. The images were analyzed both qualitatively and quantitatively. Data were analyzed with analysis of variance and the Bonferroni test or paired Student t test.
Results: Areas of high signal intensity were detected in 28% (5/18), 94% (17/18), and 89% (16/18) of patients on unenhanced cine, contrast-enhanced cine, and late gadolinium-enhanced images. In one patient, contrast-enhanced cine images revealed subepicardial areas of high signal intensity that were not visible on late gadolinium-enhanced images. The location and transmural nature of involved segments matched on contrast-enhanced cine and late gadolinium-enhanced images (both, r = 0.91, p < 0.0001). The contrast-to-noise ratio was significantly higher on contrast-enhanced cine images than on late gadolinium-enhanced images (p < 0.05).
Conclusion: Contrast-enhanced cine MRI is a valuable tool for detection of lesions of acute myocarditis and should be recommended for routine clinical MRI.