Diagnostic value of 3.0 T cardiac MRI in children with suspected myocarditis: multi-parameter analysis for the evaluation of acute and chronic myocarditis

Abstract

Background Cardiac magnetic resonance (CMR) is an established tool for detection of myocarditis. However, no comprehensive data for CMR based on the “Lake Louise” criteria in pediatric myocarditis exists to date. Purpose To evaluate the value of multi-parameter CMR in children with suspected acute (AMC) and chronic myocarditis (CMC). Material and Methods We examined 73 pediatric patients with clinically suspected AMC (n = 25) and CMC (n = 48). We compared them to 17 controls. All individuals underwent CMR, including function analyses, T2 ratio, early gadolinium enhancement ratio (EGEr), and late gadolinium enhancement (LGE). Results In AMC, 19 (76%) patients were abnormal in any two of three parameters (T2 ratio, EGEr, and LGE). There was a significant difference between AMC and controls in LVEF (51.2% vs. 61.3%), mass (130.2 ± 14.0 vs. 120.5 ± 13.9 g), T2 ratio (1.96 ± 0.2 vs. 1.69 ± 0.13), and EGEr (4.1 ± 0.27 vs. 3.4 ± 0.39) ( P < 0.05). In CMC, 26 (54.1%) patients were abnormal in any two of three parameters. There was no significant difference between CMC and controls in LVEF and mass, but there was a statistical difference in T2 ratio (1.88 ± 0.18 vs. 1.69 ± 0.13) and in EGEr (3.93 ± 0.22 vs. 3.4 ± 0.39) ( P < 0.05). There was an increase in LVEF while both T2 ratio and EGEr significantly decreased ( P < 0.05) during follow-up of acute fulminant myocarditis. Conclusion Comprehensive CMR may serve as a powerful tool in children with suspected AMC. CMR in assessment of CMC may be valuable, but it is not satisfactory.