{'fraction_non_alphanumeric': 0.036527263102170464, 'fraction_numerical': 0.011646373742721016, 'mean_word_length': 4.4, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Case 3: An 11-month-old Boy with New Bradycardia

1. Christin T. Folker, MD*
2. Joseph W. May, MD, MPH*


 

1. *Department of Pediatrics, Walter Reed National Military Medical Center, Bethesda, MD

An 11-month-old boy is brought to the emergency department for 1 day of decreased appetite, vomiting, and diarrhea. His parents have both been ill with similar symptoms, and the boy tests positive for norovirus. In the course of his evaluation, he is found to be significantly bradycardic, with a heart rate varying from 55 to 65 beats/min. His parents report an uneventful prenatal and birth history, and he has since been a healthy child. Notably, recorded heart rates were age appropriate at all previous health maintenance visits.

On examination he is fussy but consolable and is in no distress. He is afebrile, with a normal blood pressure and respiratory rate for age. He is attentive and interactive. His head is atraumatic and normocephalic, with a soft and flat anterior fontanelle. His pupils are equal, round, and reactive to light. His mucous membranes are moist, and he makes tears when he cries. Radial, brachial, and femoral pulses are of normal strength. Cardiac auscultation confirms a heart rate of 65 beat/min, a regular rhythm, and normal S1 and S2 sounds with physiologic splitting. There are no murmurs or extra heart sounds. His distal extremities are well-perfused and have a capillary refill time of less than 2 seconds. His lung fields are clear. His bowel sounds are hyperactive, and his abdomen is without hepatosplenomegaly. He has no rashes. His neurologic examination findings are grossly normal. An electrocardiogram (ECG) is ordered to further assess his bradycardia (Fig 1).



Figure 1. 
Electrocardiogram obtained at the time of presentation to the emergency department shows a narrow complex rhythm at a bradycardic rate for age (65 beats/min). Close …