Case
Hello, I’m calling from the ER at the adult hospital across the street. I have a 17-year old male who came in for palpitations. He says that he first noted them two days ago when he was hanging out with his friends. They were playing basketball and he says he felt fine at that time but went to cool off with a drink at the local convenience store. I asked about energy drinks, but he says he just had one of those cold slush drinks. Soon after that he felt his heart beating funny. He went to bed that night and when he woke up he still had the same feeling but less pronounced. He’s had school for the past few days so it wasn’t bothersome enough to skip school but today he says that he’s feeling more tired and has less energy than usual so his father brought him into the ER. When I auscultate, I hear an irregularly, irregular rhythm so I got an ECG. The ECG says that he is in atrial fibrillation! I tend to see a lot of this in our ER and it sure does look and sound like A-fib; but in a 17-year old? Should I start him on a diltiazem drip? Do I need to put him on anticoagulation?
What am I thinking?
I need to see this electrocardiogram. Atrial fibrillation is rare in the pediatric population but is possible. There may be other rhythms that could be mistakenly interpreted by the computer reading as atrial fibrillation. However, the presentation does sound characteristic of atrial fibrillation in a young adult. Given the unusual nature of this presentation, there are a number of assessments that will need to occur including history, family history, physical examination, echocardiogram, assessment of embolic risk, and ultimately decision regarding short and long-term management. In most cases, a cardioversion of the rhythm is indicated with follow-up for recurrences.
| Causes of atrial fibrillation in the pediatric/adolescent population |
|---|
| Likely |
| Underlying congenital heart disease SVT that degenerates into atrial fibrillation |
| Possible |
| Caffeine (energy drinks) Cold medications (ephedrine) Illicit drug use Vagal mediated (cold drinks) |
| Rare |
| Thyrotoxicosis Paroxysmal atrial fibrillation Genetic arrhythmia syndrome |
History and physical
Given the rarity of atrial fibrillation in the pediatric and adolescent population, the discovery of underlying substrates to set up this arrhythmia is often the primary focus for history taking. The past medical history should determine if the patient has a history of cardiac disease, either structural or electrophysiologic. For some clues, it is recommended to start with the history of present illness with specific importance as to the timing of the arrhythmia initiation as this can influence management. Additional information around surrounding environmental circumstances such as physical activity, medications, or food ingestions can be helpful. Patients have been known to present with atrial fibrillation after ingesting cold drinks such as slushies or ice cream shakes that have resulted in atrial fibrillation due to a vagal mediated response. Caffeinated beverages, stimulants such as ephedrine, or illicit drug use can induce ectopic beats that could be a set up for atrial fibrillation in the young patient. The determination of how often these types of arrhythmia symptoms are felt and with what frequency can be helpful to assess recurrence. Documentation of symptomatology will also be helpful to determine the need for ongoing monitoring. In most young people, the most common symptom is a feeling of palpitations and is often noted primarily at rest. Other associated symptomatology such as weight loss, feelings of anxiety, psychosis, and/or tremor may indicate a thyrotoxicosis. Neurologic symptoms such as weakness to one side, vision changes, dropping eyelids or lips, or speech disturbances would be highly concerning for cerebrovascular incidents (e.g., stroke, transient ischemic attack) and should be managed urgently. A family history of atrial fibrillation, particularly at a young age, may be indicative of a genetic arrhythmia syndrome.
Physical examination is usually normal in these patients, with the exception of those with underlying congenital heart disease. Atrial fibrillation may be the result of underlying conditions that serve as risk factors. These can include valvular heart disease, obesity, obstructive sleep apnea, systemic hypertension, diabetes mellitus type 2, and previous arrhythmias. As the young population becomes more obese and starts to develop disease states that are generally seen in adult populations, it is possible that atrial fibrillation will increase in the young. Cardiac auscultation should reveal the classically described “irregularly, irregular” rhythm portraying the chaotic activity of atrial fibrillation.
Diagnostic testing
An ECG is the best test to order for diagnosis of atrial fibrillation. This often demonstrates an undulating baseline that has an irregular pattern due to multiple p waves (see Fig. 19.1 ). ECGs should be interpreted by a pediatric cardiologist or ideally, an electrophysiologist. As atrial fibrillation is common in the adult population, ECG systems have an increased sensitivity to call irregular rhythms as atrial fibrillation. This can be a confounding factor in pediatric patients presenting with normal sinus arrhythmia who are erroneously labeled by the computer as having atrial fibrillation.
