Logo image
Back
26-A-7844-ACC MULTISYSTEM INFLAMMATORY SYNDROME IN CHILDREN (MIS-C) ASSOCIATED WITH RECENT COVID-19 OMICRON SUBTYPES IS RARE BUT INVOLVES SEVERE CARDIOVASCULAR FEATURES
Abstract   Peer reviewed

26-A-7844-ACC MULTISYSTEM INFLAMMATORY SYNDROME IN CHILDREN (MIS-C) ASSOCIATED WITH RECENT COVID-19 OMICRON SUBTYPES IS RARE BUT INVOLVES SEVERE CARDIOVASCULAR FEATURES

Rabia Siddiqi Khan and Gary S. Beasley
Journal of the American College of Cardiology, Vol.87(13 Supplement), pp.A534-A535
04/2026
DOI: 10.1016/j.jacc.2026.02.1445

View Online

Abstract

Background Multisystem inflammatory syndrome in children (MIS-C) following COVID-19 was identified in the United States in 4/2020. Cardiovascular features include ventricular dysfunction, coronary dilation, and systemic vasodilation. Prior reports show that severity of the cardiovascular findings decreased with emergence of the Omicron variant in late 2021. Recent CDC variants of concern are Omicron subtypes originating from JN.1, which became the predominant subtype in 1/2024. Methods This single center study compares MIS-C prevalence and its cardiovascular findings in pediatric patients who developed MIS-C in 1/2024 or later to those associated with prior Omicron subtypes (1/2022-12/2023). Results Six patients were hospitalized with MIS-C from 1/2024 to 4/2025 compared to 26 from 1/2022 to 12/2023 (p=0.014). All six from recent cohort developed left ventricular dysfunction compared with four from prior (6/6 vs 4/26, p=0.0002). The ejection fraction at presentation of those with dysfunction was 15-44% in the recent cohort, lower than 46-56% in the prior (p=0.024). Troponin elevation was found in all six from recent cohort and in 11 from prior (6/6 vs 11/26, p=0.019). Vasodilation requiring vasopressor support occurred in five from recent cohort and only two from prior (5/6 vs 2/26, p=0.016). Two patients from recent cohort were supported with venoarterial extracorporeal membrane oxygenation (VA-ECMO), of which one died of intractable vasodilation. Coronary dilation was not seen in the recent cohort and rare in the prior (0/6 vs 2/26, p=1). Aside from the one who did not survive to discharge, the remainder of patients from both cohorts had complete resolution within one week. Conclusion This study demonstrates that MIS-C is rare in the recent era, though the significance is unclear without comparing frequency of COVID-19 infection. Compared to MIS-C following prior Omicron subtypes, recent occurrences are associated more cardiovascular features. Despite reassuring cardiac outcomes, the recent illness severity and inability to support one patient despite VA-ECMO suggest that continued vigilance is essential.

Details

Metrics

1 Record Views
Logo image