Assistant Professor of Pediatrics Children's Heart Institute, Children's Memorial Hospital, UT Houston Houston, Texas, United States
Abstract:
Introduction: Acute myocarditis can have a wide spectrum of presentation from asymptomatic to potentially lethal disease in children. Lack of defined diagnostic criteria makes its diagnosis dependent on clinical suspicion. The objective of this study was to explore the current trends in demographics, clinical manifestations, treatments, and outcomes in the United States.
Methods: This retrospective study was conducted using data collected from the Pediatric Health Information System (PHIS) database for the years 2014-2020. We included patients 21 years or younger with a primary diagnosis of acute myocarditis. The statistical analysis was performed using Chi-square and continuous variables using Mann Whitney U Test for continuous data comparisons.
Results: We found 1199 patients with acute myocarditis. The mean age was 12.2 years with a male preponderance for adolescent ages. About 60% of patients required admission to the intensive care unit (ICU). The median hospital LOS was four days for all patients and six days for ICU patients. Two hundred sixty-five (22.1%) patients required invasive mechanical ventilation, 127 (10.6%) required Extracorporeal membrane oxygenation, 33 (2.8%) required Ventricular assist device and 22 (1.8%) required cardiac transplantations. Milrinone was the most frequently used vasoactive agent. The overall mortality was 2.3%. IVIG infusion use decreased during the study period. On multivariate analysis, vasoactive medication use, (p < 0.01) and arrythmia (p = 0.02) were independently associated with increased odds of mortality. IVIG use (p=0.01) was associated with decreased odds of mortality.
Conclusion: Despite high morbidity and frequent need for advanced life support measures, the survival outcomes in children affected by acute myocarditis in the United States is favorable. Vasoactive support and arrythmia are independently associated with increased mortality while IVIG administration is associated with decreased mortality.
