Cardiac MRI in midterm follow-up of MISC: a multicenter study.

Area of Science:

• Pediatric Cardiology
• Infectious Diseases
• Cardiovascular Imaging

Background:

• Heart involvement is frequent in multisystem inflammatory syndrome in children (MIS-C).
• Previous studies show conflicting results on cardiac outcomes in MIS-C patients assessed by cardiac MRI.
• Mid-term cardiac MRI reveals mild abnormalities in recovered MIS-C patients, irrespective of initial cardiac involvement severity.

Purpose of the Study:

• To evaluate the mid-term cardiac outcomes in children diagnosed with MIS-C using cardiac magnetic resonance (CMR).
• To assess the presence and extent of cardiac abnormalities in MIS-C survivors.

Main Methods:

• A multicenter retrospective study involving 20 pediatric patients diagnosed with MIS-C between February 2020 and November 2021.
• Patients underwent cardiac magnetic resonance (CMR) during follow-up visits.
• Data collected included demographics, clinical presentation, laboratory results, treatments, and cardiac imaging findings.

Main Results:

• Twenty MIS-C patients (median age 12 years) were included.
• Acute phase cardiac involvement included hypotension/shock (55%), myocardial involvement (100%), reduced LV ejection fraction (83%), and need for inotropes (40%).
• Mid-term CMR (median 3 months post-discharge) showed pericardial effusion/myocardial edema (5%), mild residual LV dysfunction (20%), and minimal myocardial scars (25% via LGE).

Conclusions:

• Despite severe acute cardiac involvement, mid-term cardiac outcomes in MIS-C patients are generally good.
• Mild cardiac abnormalities may persist in the mid-term follow-up.
• Direct cardiac viral invasion is a potential factor in MIS-C pathogenesis.