A Case of Pediatric Myocarditis that was Initially Misdiagnosed as Cerebral Concussion

Abstract

A seven-year-old girl suddenly fell and became unconscious in her house. Her mother, who witnessed the fall called an ambulance. While waiting for the ambulance, she experienced generalized convulsions. The emergency medical technicians reported to the hospital that the patient had experienced cerebral concussion and immediate post-traumatic seizure. During transportation, she experienced generalized convulsions again. Electrocardiography (ECG) showed complete atrioventricular block without QRS complex during the generalized convulsions. On arrival, she regained consciousness. ECG revealed sinus tachycardia with left axis deviation and negative T wave at the I, aVL, V1-V3 leads. Cardiac echo showed good wall motion with a highly echoic epicardium. Head computed tomography revealed no specific findings. The main blood test results were increased cardiac enzyme and inflammatory reaction. The diagnosis was myocarditis and fatal arrhythmia followed by generalized convulsions and/or syncope, not cerebral concussion. She was transported to a children’s hospital for advanced medical care. Her post-admission course was uneventful. Adenovirus was the causative virus of myocarditis. The present case suggests that the heart should be evaluated in addition to the brain when children experience a prolonged period of unconsciousness after a fall.