Evaluation of Long-Term Cardiac Function in MIS-C Patients Using Speckle Tracking Echocardiography

Multisystem inflammatory syndrome in children (MIS-C) is associated with cardiac involvement in 67%-80% of cases. Cardiac symptoms often normalize rapidly after treatment, but few studies are available on the long-term cardiac effects.

Our study evaluated the cardiac functions of 40 patients diagnosed with MIS-C between August 2021 and November 2022. Conventional echocardiography (ECHO), electrocardiography (ECG), speckle tracking echocardiography (STE), and cardiac MR were performed at the time of diagnosis and 3-nd 6-month follow-up.

Of the 40 patients, 65% (26) were male and 35% (14) were female. The average age at diagnosis was 8.37 ± 4.59 years (range 2-17). Systolic dysfunction was observed in 11(27.5%) patients on conventional ECHO; two patients (5%) required extracorporeal membrane oxygenation (ECMO) support. All patients showed rapid normalization of conventional ECHO findings with treatment. At the 3-month follow-up, no abnormalities in left ventricle ejection fraction (LVEF) and fractional shortening (LVFS) were detected on conventional ECHO, but STE revealed contraction abnormalities in the mid-inferior and apical inferior regions of the two-chamber view, the basal inferoseptal and mid-anterolateral regions of the four-chamber view, though improvement was noted compared to initial findings. At the 6-month follow-up, only a minimal contraction abnormality persisted in the two-chamber mid-inferior region. Cardiac MR performed at 1 year in 8 (20%) patients revealed normal results.

The cardiac effects of MIS-C were found to improve rapidly with treatment. STE is a valuable tool for detecting and monitoring regional contraction abnormalities in MIS-C patients.