Atrial Flutter: An Uncommon Pediatric Manifestation of Hyperthyroidism

Abstract

ABSTRACT. Objective. Atrial flutter is an uncommon arrhythmia in the pediatric population except for the immediate newborn period or following atrial repair of congenital heart disease. In children the diagnosis of atrial flutter may be difficult, attributable to rapid atrioventricular conduction and superimposition of flutter waves on QRS and T waves. Atrial flutter secondary to hyperthyroidism has been rarely reported in older adults, but there are no reports of children presenting with atrial flutter as the initial manifestation of hyperthyroidism.Case Report. We report an interesting case of hyperthyroidism in a 3-year-old presenting with congestive heart failure and atrial flutter with 1:1 atrioventricular conduction. The responses to adenosine administration and to cardioversion were unusual and ultimately helpful in suggesting the diagnosis of hyperthyroidism.Conclusion. When atrial flutter is encountered in a pediatric patient in whom there is 1:1 atrioventricular conduction, a lack of a response to adenosine, and persistent sinus tachycardia after cardioversion, the clinician should be alert to the possibility of thyrotoxicosis. Pediatrics 1997;100(2). URL: http://www.pediatrics.org/ cgi/content/full/100/2/e11; atrial flutter, hyperthyroidism, pediatric, adenosine.A trial flutter is an uncommon arrhythmia in the pediatric population. It is principally encountered in the newborn period or after atrial repair of congenital heart disease. Although hyperthyroidism is clearly known to be a cause of atrial flutter in older adults, 1,2 there are no reports of children presenting with atrial flutter as the initial manifestation of thyrotoxicosis.When children present with atrial flutter, the diagnosis is often difficult, attributable to rapid atrioventricular conduction and superimposition of flutter waves on QRS and T waves. The presence of hyperthyroidism would be expected to further affect these relationships. We report here an interesting case of thyrotoxicosis in a 3-year-old presenting with atrial flutter in whom the response to adenosine administration and to cardioversion were unusual and ultimately helpful in suggesting the diagnosis of thyrotoxicosis. CASE REPORTA 3-year-old black girl presented with an increased heart rate noted for 9 hours and decreased activity. She had a similar episode of "fast heart rate" 2 days previously. She had no history of fever, heat intolerance, neck pain, significant weight loss or hoarseness, but was extremely hyperactive. Her past medical history was only remarkable for scarlet fever treated with amoxicillin 2 months before admission. The family history was remarkable for a maternal aunt with an overactive thyroid and another cousin with insulin-dependent diabetes mellitus.On physical examination, she was 17.3 kg and had a regular heart rate of 275 beats/minute, respiratory rate of 66 breaths/ minute, blood pressure of 111/78 mm Hg, and a axillary temperature of 37.7°C. She had moderate retractions. There was a nontender, enlarged thyroid gland. The lung fields were c...

A not so benign atrial flutter: spontaneous 1:1 conduction of atrial flutter

“…Accessory AV conduction pathways connecting the atria to the ventricles can cause fast conduction of impulses through AV node increasing the likelihood of 1:1 conduction in AFL 5. Conditions like hyperthyroidism that potentiates AV conduction may occasionally result in 1:1 AFL conduction 6. Exercise may also cause 1:1 AV conduction owing to both increased flutter cycle length and enhanced AV conduction 7.…”

Hyperthyroidism With Atrial Fibrillation in Children: A Case Report and Review of the Literature

“…However, it is a rare occurrence in children ( 1 ). To date, there have been three reported cases of hyperthyroidism accompanied by AF in children ( 2 – 4 ), and one reported case of atrial flutter associated with hyperthyroidism ( 5 ). We report a rare case of a 15-year-old female with hyperthyroidism complicated by AF.…”