MIS-C and Cardiac Conduction Abnormalities

Pediatrics. 2020 Dec;146(6):e2020009738. doi: 10.1542/peds.2020-009738. Epub 2020 Nov 12.

Abstract

Objectives: Multisystem inflammatory syndrome in children (MIS-C) has spread through the pediatric population during the coronavirus disease 2019 pandemic. Our objective for the study was to report the prevalence of conduction anomalies in MIS-C and identify predictive factors for the conduction abnormalities.

Methods: We performed a single-center retrospective cohort study of pediatric patients <21 years of age presenting with MIS-C over a 1-month period. We collected clinical outcomes, laboratory findings, and diagnostic studies, including serial electrocardiograms, in all patients with MIS-C to identify those with first-degree atrioventricular block (AVB) during the acute phase and assess for predictive factors.

Results: Thirty-two patients met inclusion criteria. Median age at admission was 9 years. Six of 32 patients (19%) were found to have first-degree AVB, with a median longest PR interval of 225 milliseconds (interquartile range 200-302), compared with 140 milliseconds (interquartile range 80-178) in patients without first-degree AVB. The onset of AVB occurred at a median of 8 days after the initial symptoms and returned to normal 3 days thereafter. No patients developed advanced AVB, although 1 patient developed a PR interval >300 milliseconds. Another patient developed new-onset right bundle branch block, which resolved during hospitalization. Cardiac enzymes, inflammatory markers, and cardiac function were not associated with AVB development.

Conclusions: In our population, there is a 19% prevalence of first-degree AVB in patients with MIS-C. All patients with a prolonged PR interval recovered without progression to high-degree AVB. Patients admitted with MIS-C require close electrocardiogram monitoring during the acute phase.

MeSH terms

  • Adolescent
  • Atrioventricular Block / diagnosis
  • Atrioventricular Block / epidemiology*
  • Atrioventricular Block / etiology
  • Atrioventricular Block / physiopathology
  • Bundle-Branch Block / diagnosis
  • Bundle-Branch Block / epidemiology
  • Bundle-Branch Block / etiology
  • COVID-19 / complications
  • COVID-19 / diagnosis
  • COVID-19 / epidemiology*
  • COVID-19 Drug Treatment
  • COVID-19 Nucleic Acid Testing
  • COVID-19 Serological Testing / statistics & numerical data
  • Child
  • Child, Preschool
  • Electrocardiography
  • Female
  • Humans
  • Infant
  • Intensive Care Units, Pediatric / statistics & numerical data
  • Male
  • New York City / epidemiology
  • Prevalence
  • Retrospective Studies
  • Systemic Inflammatory Response Syndrome / complications
  • Systemic Inflammatory Response Syndrome / diagnosis
  • Systemic Inflammatory Response Syndrome / drug therapy
  • Systemic Inflammatory Response Syndrome / epidemiology*
  • Young Adult

Supplementary concepts

  • pediatric multisystem inflammatory disease, COVID-19 related