Atrial tachycardia in infants and children: Electrocardiographic classification and its significance

Abstract

An electrocardiographic classification of atrial tachycardia and its significance in children has not been reported. We reviewed the clinical histories and 12-lead surface electro-cardiograms (ECG) of 21 children with atrial tachycardia. Atrial rate and P-wave axis were determined for each patient. Some patients had features of typical atrial flutter (AF). Tachycardia was classified by atrial rate < 340/min or atrial rate > 340/min. Children with atrial tachycardia rate > 340/min consistently responded to conservative treatment (digoxin and/or cardioversion) without recurrences (p < 0.05 and p > 0.025); whereas in children with atrial rate < 340/min, only one case responded to conservative therapy. P-wave axis had no prognostic significance for either group. Additionally, high atrial rate (> 340/min) during tachycardia was noted in early infancy, compared to older children and adults, and probably represents the function of age. Classification of atrial tachycardia by rate is clinically useful for planning therapy and predicting response in children.

Focal Atrial Tachycardia I: Clinical Features, Diagnosis, Mechanisms, and Anatomic Location

“…The atrial rate during focal AT usually ranges between 130 and 250 beats/min, but may be as low as 100 beats/min or as high as 300 beats/min. In general, younger patients tend to have faster AT, with rates up to 340 beats/min described in infants 10 . The properties of the atrial focus may be similar to that of the sinus node in that they are responsive to changes in activity and autonomic tone.…”

Focal atrial tachycardia

“…Episodes may last only a few seconds or hours within an individual patient. The atrial rate during focal AT is typically variable ranging between 130 and 250 beats/min, but may be as low as 100 beats/min or as high as 300 beats/min, especially in young patients and infants 23. The clinical course is usually benign, although incessant tachycardia may result in a cardiomyopathy.…”

NASPE Expert Consensus Conference: Radiofrequency Catheter Ablation in Children with and without Congenital Heart Disease. Report of the Writing Committee

“…Atrial flutter in pediatric patients with structurally normal hearts presents most commonly in neonates and young infants; two thirds are diagnosed by the first day of life. [17][18][19][20] Recurrence of atrial flutter in this population is exceedingly uncommon outside of the immediate newborn period. 21…”