Purpose or Case Report: As more pediatric patients are infected with severe acute respiratory syndrome coronavirus 2 during the coronavirus disease 2019 (COVID-19) pandemic, more have been diagnosed with multisystemic inflammatory syndrome in children (MIS-C). Early research investigations into MIS-C show cardiac involvement presenting as elevated troponins, ventricular dysfunction, electrical conduction abnormalities, and pericardial effusions. MIS-C may result in myocardial perfusion defects visualized with nuclear medicine imaging and magnetic resonance imaging (MRI), however these perfusion defects on contrast enhanced computed tomography (CT) have not yet been described.
Methods & Materials: An institutional radiology electronic database search for “MIS-C”, “MISC”, “COVID”, and “COVID-19” in either the report or requested indication was performed. Exams were included if intravenous contrast was given and in the descending aorta, the entirety of the heart was seen, and if performed on a spectral detector CT scanner. A review was performed to confirm the diagnosis of coronavirus infection prior to the CT and clinical diagnosis of MIS-C.
Iodine maps of the myocardium and presence or absence of regional perfusion abnormality was recorded. Circular regions of interest (ROI) were drawn in the left ventricular myocardium at the area of visually decreased and visually normal perfusion. The Hounsfield units (HU) and iodine map (mg/mL) values were recorded for each ROI.
Results: The initial search found 40 exams in 37 patients with six exams on six different patients meeting inclusion criteria. All six patients demonstrated perfusion defects on visual inspection of static iodine map images. Because of differences in exact contrast bolus timing, no definite quantitative threshold could be determined.
Chart review and review of imaging showed other findings of MIS-C and COVID-19 pneumonia. All patients had reported chest pain at rest and worsening with exertion. Four had elevated troponin levels while toponin levels were not available for the other two.
Conclusions: Myocardial perfusion defects can be visualized on contrast enhanced SDCT in patients with MIS-C from COVID-19. Creating iodine maps of the myocardium increases confidence that differences in attenuation are truly from myocardial perfusion abnormalities. When obtaining contrast enhanced CT in children with COVID-19, performing the exam on a SDCT scanner with appropriate contrast timing can visualize MIS-C related myocardial perfusion abnormalities.