Experience in the management of infants with multifocal atrial tachycardia

Abstract

Purpose. To study the clinical course of multifocal atrial tachycardia (MAT) and to evaluate the effectiveness of antiarrhythmic therapy (AAT) in patients with onset of arrhythmia before the age of 1 year.Methods. The study included 15 children with primary registration of MAT at the age of 2.04±2.27 months, 4 of them - in utero. The follow-up period was 35.9±26.9 months (Me 29 months). All patients underwent laboratory monitoring, 12-lead ECG recording, 24-hour ECG monitoring, echocardiography at baseline and during time of observation.Results. Tachycardia was persistent in 80% of patients. Tachycardia-induced cardiomyopathy (TIC) was present in 7 (46%) patients. Structural heart disease was detected in 6 patients. The average heart rate at the onset of the disease was 157.9±23.78 bpm, the maximum - 256.7±35.84 bpm. Fourteen (93.3%) children received AAT. Seven patients were prescribed propranolol first, 6 - amiodarone, 1 - digoxin. Monotherapy was effective in 2 patients. Combined AAT was used in 12 patients, including three children with three drugs combination. No benefits were found for any of the drugs combinations. Stable sinus rhythm at the time of discharge was observed in 4 (28,6%) patients, sinus rhythm with atrial ectopic activity was registered in 2 of them; criteria for normosystole were achieved in 7 patients; in one child with TIC daytime tachysystole persisted despite three-component AAT, but echocardiography parameters improved. Arrhythmia was disappeared in 13 (86.6%) patients; the duration of arrhythmia in them from 1 to 15 months, duration of AAT - 1 ±7.5 months (Me 9.5 months). MAT persists in two patients with structural heart disease. One patient underwent radiofrequency ablation at the age of 5, with no effect. One patient had side effects from therapy that required correction. There were no lethal outcomes.Conclusion. MAT with a debut at the age of 1 year with timely prescribed treatment has a favorable course and a good prognosis, but the probability of AAT resistance is high. These cases require a long-term selection of therapy using various combinations of antiarrhythmic drugs. Heart rate control strategy can be sufficient to prevent the development of TIC.