Multiple Cardiac Arrhythmias in a Previously Healthy Child

Abstract

We present a case of multiple arrhythmias in a 3-year-old child who was presented to the emergency department with emesis. Initial vital signs were significant for a heart rate from 40 to 60 beats per minute with stable blood pressure. An electrocardiogram showed complete atrioventricular block with a junctional escape rhythm of 40 to 55 bpm that subsequently progressed to atrial flutter/fibrillation and then to a junctional escape rhythm. She was given intravenous atropine, resulting in acceleration of the junctional rhythm. Sinus rhythm resumed with a prolonged PR interval a few hours later with normalization of the electrocardiogram the following day. Routine laboratory tests, toxicology screens, and tests for other cardiac medications in the home were negative. However, at 20 hours after presentation, her digoxin level was 2.9 ng/mL. Parents denied that the child had access to any digoxin-containing substances. This case illustrates that digoxin toxicity can manifest with multiple arrhythmias and that recognition of this can be very difficult, especially when there is no witness to ingestion. Clinicians should be suspicious for digoxin toxicity when a child presents with persistent emesis, altered level of consciousness, and bradyarrhythmias with or without hemodynamic instability.