Cardiac follow-up should be common practice after MIS-C diagnosis, say researchers

Following multisystem inflammatory disease in children (MIS-C), cardiac abnormalities are common, regardless of myocardial injury during acute disease, according to a study published online Nov. 15 in Pediatrics.

Dayna Zimmerman, M.D., from Children's Hospital Los Angeles, and colleagues assessed the prevalence of residual cardiovascular pathology by cardiac magnetic resonance imaging (CMR), ambulatory rhythm monitoring, and cardiopulmonary exercise testing (CPET) in patients six months after MIS-C. Analysis included 153 patients seen for MIS-C follow-up (October 2020 to June 2022).

The researchers found that 45 percent of patients had one or more follow-up cardiac study. More than half (54 percent; 37 patients) had evidence of myocardial injury during acute illness. Of these, 46 percent had one or more abnormality on CMR, 12 percent had abnormal ambulatory rhythm monitor results, and 82 percent had reduced functional capacity on CPET.

Among participants without apparent myocardial injury, still 52 percent had one or more abnormality on CMR, 4 percent had an abnormal ambulatory rhythm monitor result, and 73 percent had reduced functional capacity on CPET.

"The high prevalence of abnormal findings on follow-up cardiac studies and lack of significant difference between patients with and without apparent myocardial injury during hospitalization suggests that all patients treated for MIS-C warrant cardiology follow-up," the authors write.