Objective:

To evaluate the patterns of cardiovascular involvement in patients with MIS-C associated with the SARS-CoV-2 Omicron variant and compare findings between earlier Omicron subtypes and newer subtypes from the JN.1 lineage.

Approach:

• Study Design: Retrospective review of hospitalized patients under 18 years with MIS-C at a single tertiary referral center over 28 months.
• Inclusion Criteria: Patients meeting CDC diagnostic criteria for MIS-C with confirmed COVID-19 infection.
• Exclusion Criteria: Patients not meeting diagnostic criteria or with alternative diagnoses.
• Data Collection: Demographic, laboratory, and cardiovascular data were collected from electronic medical records.

Key Findings:

• Cardiac involvement occurs in up to 80% of MIS-C patients.
• Cardiovascular manifestations were most severe following Delta variant infections.
• A decrease in cardiovascular manifestations was observed with Omicron variant infections.
• The emergence of the JN.1 subtype has led to a lack of data on MIS-C presentation.

Interpretation:

Limitations:

• Single-center study may limit generalizability.
• Retrospective design may introduce bias.

Conclusion: