Non-invasive pediatric cardiac imaging—current status and further perspectives

Figures

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  Fig. 1. 2D strain imaging allows the assessment of global and regional function based on the determination of qualitative and quantitative parameters (longitudinal, radial, circumferential strain): vendor-independent analysis software tools (such as the Tomtec 2D-CPA analysis) visualize LV myocardium, strain curves, and summarize the results in “bull-eye” plots, generating a fast and comprehensive overview on cardiac function

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  Fig. 2. (Planning and dose monitoring): first steps are a fast low-dose overview (“topogram/sinogram”; left) and a stable ECG monitoring (right) for triggering (prospective mode) or gating (retrospective mode). Figures 2 and 3 derive from the CT of a 15-year-old girl after surgical repair of a malignant coronary anomaly (origin of the left main from the right coronary sinus) with reinsertion of the left main coronary artery with an ultra-low radiation dose (total DLP 9 mGycm ~ 0.2 mSv)

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  Fig. 3. (Representative images for the primary CT datasets): based on primary axial planes (left), different positions in long-axis heart orientation (right upper row) and parasagittal orientation (right lower row) are depicted. Currently, these standard projections are reconstructed by specifically trained technicians; increasingly AI-based algorithms take over these time-consuming tasks

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  Fig. 4. (2D postprocessing): automatically 2D recontructions of the three main coronary arteries are generated, here the LAD in curved (left) and straight (right) MIP projections; this allows a rapid assessment at first sight and facilitates the review of finding by the referring physicians

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  Fig. 5. (Functional imaging): assessment of cinematographic (“CINE”) images allows a rapid overview of global and regional functions comparable to echocardiography. Standard are planned projections in the long- and short-heart axis. Here, images of a 12-year-old girl with follow-up after multisystem inflammatory syndrome in children (PIMS) are presented: a 4-chamber view in diastole (left upper row) and systole (left lower row) and a 2-chamber view also in diastole (middle) and systole (right)

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  Fig. 6. (Tissue integrity assessment by T2 and LGE imaging): the capability of a non-invasive complete assessment of tissue integrity (edema yes/no, fibrosis yes/no) is one of the hallmarks of MRI. Healthy myocardium shows a dark (“hypointense”) signal in T2 imaging (first two images in the left upper row) as well as a dark signal in LGE imaging (right upper row LGE-SAX in IR and PS reconstruction; lower row—LV 2CV- and 4 CV-LGE)

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  Fig. 7. (Mapping technologies): qualitative (based on color maps) and quantitative (based on signal intensities) assessment is possible; in comparison to values of healthy cohorts, increased T2 values indicate myocardial edema and increased T1 values indicate fibrosis; here, healthy myocardium is depicted for SAX-T2- (left) and pre-contrast (“native”) T1 mapping (right) in midventricular position

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  Fig. 8. (Functional imaging): a 4-chamber view and axial CINE allow the measurement of the size of the ASD (diameters) plus the illustration of concomitant “jets” (increased and turbulent flow produces hypointense blood signals)

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  Fig. 9. (MRA): time-resolved contrast-enhanced MRA in coronal and transversal reconstructions (MIP projections) allow a complete overview of the anatomy of large vessels and the monitoring of shunting (left-right; right-left)

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  Fig. 10. (2D flow): left–right shunting due to the ASD. Flow is depicted morphologically (“magnitude images,” left lower row) and hemodynamically (“phase-images, left upper row and middle lower row”); the latter allows a quantitative assessment of velocities, directions, and flow profiles (upper row in the middle)

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  Fig. 11. (Functional and anatomic imaging by CINE): 4CV, 3CV, 2CV, and axial CINE show the enlarged and hypertrophied LV as well as the TCPC

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  Fig. 12. (MRA): connection between VCS, VCI, and right pulmonary artery. The 4 smaller images show the connections (upper and lower images on the left as single images in high resolution; upper and lower images in the middle as thicker MIPs for an overview). The right larger image is one data set of the MR angiography, which gives an idea about pulmonary blood flow