Diagnostic evaluation of pediatric myocarditis in the emergency department: a 10-year case series in the Asian population.

OBJECTIVES: Pediatric myocarditis is a known cause of dilated cardiomyopathy and is associated with significant mortality. Our primary objective was to describe the frequency of presenting symptoms, signs, and investigation results among children diagnosed with acute myocarditis. Our secondary objective was to review these patients' initial diagnoses by the emergency physicians.

METHODS: This was a retrospective chart review of all patients younger than 16 years who were diagnosed with acute myocarditis in our hospital over a 10-year period (January 2001 to December 2010). The symptoms and signs were stratified according to age (infants, 1-5 years, 6 years or older).

RESULTS: Thirty-nine children met the search criteria, of whom 10 patients (25.6%) were definite cases proven by myocardial biopsy. The average age was 5.4 years (SD, 4.3 years). The most common symptom complex was that of hypoperfusion (61.5%), which consisted of lethargy (53.8%), syncope (23.1%), and seizure (23.1%). Only 4 patients had cardiac symptoms, and all were older than 6 years old. Hepatomegaly was present in 16 patients (41.0%), whereas gallop rhythm or cardiac murmur was heard only in 5 patients (12.8%), Chest radiographs showed abnormalities in only 21 cases (53.8%), whereas all had abnormal electrocardiogram findings. Fifteen cases (38.5%) were diagnosed correctly at initial presentation, whereas the most common misdiagnosis was that of respiratory tract infections (20.5%).

CONCLUSIONS: Pediatric myocarditis rarely presents with specific cardiac symptoms in the younger population. Any child with symptoms and signs of hypoperfusion, especially unexplained seizure or syncope, should have an electrocardiogram performed.