Clinical Features, Management and Outcomes of Supraventricular Tachycardia in Newborns: A 10‐Year Multicenter Experience

Aim Neonatal supraventricular tachycardia lacks neonatal‐specific evidence to guide therapy. Methods We retrospectively collected data of neonates with supraventricular tachycardia across two Italian centres between 2014 and 2024. Clinical features, mechanisms, echocardiography, biomarkers, acute and maintenance therapy were collected; outcomes included recurrences, intensive‐care admission, electrophysiology and ablation. Results Thirty‐two infants were included (59% male; median onset 14 days). Among the supraventricular tachycardia mechanisms, we identified atrioventricular reentrant tachycardia in 72%, AV‐nodal reentrant tachycardia in 9%, permanent junctional reciprocating tachycardia in 9%, focal atrial tachycardia in 9%. Median ejection fraction was 60% overall and 39% in those with heart failure; tachycardia‐induced cardiomyopathy occurred in 28%. First‐episode termination was spontaneous in 13%, achieved with vagal manoeuvres in 28% and adenosine in 47%. Maintenance therapy was required in 97% for a median of 21 months. During a mean 3.75‐year Follow‐up, recurrence after withdrawal occurred in 3; electrophysiology was performed in 3 and ablation in 2. Elevated NT‐pro‐brain natriuretic peptide and focal atrial tachicardia/permanent junctional reciprocating tachycardia phenotypes correlated with greater therapy burden. Conclusions Atrioventricular reentrant tachycardia predominates in neonatal supraventricular tachycardia. While acute control is usually attainable, sustained control often requires prolonged combination therapy. Early mechanism assignment and biomarker‐informed risk stratification may guide step‐up treatment, and catheter ablation is a viable option for refractory cases beyond infancy.