Normal Ventricular and Regional Blood Flow Volumes and Native T1 Values in Healthy Japanese Children Obtained from Comprehensive Cardiovascular Magnetic Resonance Imaging

Abstract

Age-related mean and reference ranges for ventricular volumes and mass, regional blood flow measurements, and T1 values using cardiovascular magnetic resonance (CMR) imaging are yet to be established for the pediatric population. Especially in infants and toddlers, no consistent flow volume sets or T1 values have been reported. The purpose of this study was to determine the relevant normal values.Twenty-three children (aged 0.1-15.3 years) without cardiovascular diseases were included. Comprehensive CMR imaging including cine, 2-dimensional phase-contrast, and native T1 mapping, were performed. Ventricular volumes and masses, 11 sets of regional blood flow volumes, and myocardial and liver T1 values were measured. All intraclass correlation coefficient values were > 0.94, except for the right ventricular mass (0.744), myocardial (0.868) and liver T1 values (0.895), reflecting good to excellent agreement between rates.Regression analysis showed an exponential relationship between body surface area (BSA) and ventricular volumes, mass, and regional blood flow volumes (normal value = a*BSA b ). Left ventricular myocardial T1 values were regressed on linear regression with age (normal value = -7.39*age + 1091), and hepatic T1 values were regressed on a quadratic function of age (normal value = 0.923*age 2 -18.012*age + 613).Comparison of the 2 different methods for the same physical quantities by Bland-Altman plot showed no difference except that the right ventricular stroke volume was 1.5 mL larger than the main pulmonary trunk flow volume.This study provides the normal values for comprehensive CMR imaging in Japanese children.

Native liver T1 mapping on magnetic resonance imaging for an evaluation of congestive liver injury in children with congenital heart disease

“…Leah et al reported that the median LT1 in controls measured by 1.5-T MRI, was 569 ± 39 ms (range, 529-646; n = 12; mean age, 12.2 ± 3.1 years), similar to our control data. In this report, there was no signi cant association between age and LT1 [18], but this was not observed in our study, similar to our previous report [17]. Compared with these control data, the LT1 of the BVR and bidirectional Glenn circulation groups were almost the same as the control data, while the LT1 of the Fontan circulation group was higher in our study.…”

“…Although no healthy control was included in this study, the mean LT1 of healthy controls measured by 1.5-T MRI at our institution was 552 ± 42 ms (n = 23, mean age: 7.2 ± 4.9 years) [17]. Leah et al reported that the median LT1 in controls measured by 1.5-T MRI, was 569 ± 39 ms (range, 529-646; n = 12; mean age, 12.2 ± 3.1 years), similar to our control data.…”