What is the recommended cardiac follow-up for a child with Multisystem Inflammatory Syndrome in Children (MIS-C) after hospital discharge?

Recommended Cardiac Follow-Up for Children with MIS-C After Hospital Discharge

All children with MIS-C should have echocardiograms repeated at a minimum of 7-14 days and 4-6 weeks after initial presentation, with abnormal BNP and/or troponin T levels trended until normalization. 1

Routine Follow-Up Protocol

Initial Follow-Up (1-2 weeks post-discharge)

• EKG evaluation
• Echocardiogram including:
  • Ventricular/valvular function assessment
  • Pericardial effusion evaluation
  • Coronary artery dimensions with z-scores indexed to body surface area 1
• Laboratory monitoring:
  • BNP/troponin T levels (if abnormal at diagnosis, continue until normalized) 1
  • Inflammatory markers (CRP, ESR) if previously elevated

4-6 Week Follow-Up

• Repeat echocardiogram with same parameters as initial follow-up
• EKG evaluation
• Final laboratory assessment if values haven't normalized

Extended Follow-Up Based on Clinical Findings

For Patients with Cardiac Abnormalities During Acute Phase

• Left Ventricular Dysfunction

  • More frequent echocardiograms (every 2-4 weeks until normalized) 1
  • Cardiac MRI at 2-6 months post-diagnosis for patients who had:
    • Significant transient LV dysfunction (ejection fraction <50%) during acute phase
    • Persistent LV dysfunction 1, 2
  • MRI should include:
    • Functional assessment
    • T1/T2-weighted imaging
    • T1 mapping and extracellular volume quantification
    • Late gadolinium enhancement 1

• Coronary Artery Abnormalities (CAAs)

  • More frequent echocardiograms (every 2-4 weeks) 1
  • Consider cardiac CT for suspected distal CAAs not well visualized on echocardiogram 1
  • One-year follow-up echocardiogram 1

• Conduction Abnormalities

  • Holter monitoring during follow-up 1
  • More frequent EKG monitoring

One-Year Follow-Up

• Echocardiogram for patients who had any cardiac abnormalities during acute phase 1

Risk Stratification for Follow-Up Intensity

Recent research suggests certain factors may warrant closer monitoring:

• Patients with hypotension during hospitalization
• ICU admission
• Any LVEF <55% during hospitalization
• Peak CRP >18 mg/dL during hospitalization 3

Important Considerations and Pitfalls

1. Subclinical Dysfunction: Recent studies show that subclinical myocardial dysfunction may persist in some patients despite normalization of ejection fraction. Up to 13-18% of patients may have abnormal strain parameters at follow-up despite normal LVEF 4, 3. This highlights the importance of thorough echocardiographic assessment.

2. Late Cardiac Findings: Cardiac MRI performed 2-6 months after diagnosis may reveal abnormalities even in patients with normal echocardiograms. One study found that 61.3% of patients had at least one abnormal finding on cardiac MRI performed at least 3 months after diagnosis 2.

3. Persistent Fibrosis: Some patients may develop myocardial fibrosis that can be detected on cardiac MRI, even after normalization of other cardiac parameters 5. This supports the recommendation for cardiac MRI in patients who had significant LV dysfunction.

4. Arrhythmias: Ventricular arrhythmias may develop during follow-up, even in patients who initially did not show cardiac involvement 5. This emphasizes the importance of EKG monitoring during follow-up visits.

5. Follow-Up Timing: While most patients show rapid improvement in cardiac function, recent evidence suggests that a 4-6 week window for the first follow-up visit after discharge is reasonable for most patients 6, though guidelines recommend an earlier visit at 7-14 days.

By following this structured cardiac follow-up protocol, clinicians can effectively monitor and manage potential cardiac sequelae in children recovering from MIS-C, with the goal of optimizing long-term outcomes and quality of life.