Postoperative junctional ectopic tachycardia with variable QRS morphology: A case report
Luka Lovrenčić1, Matija Bakoš1
1Department of Pediatrics, University Hospital Center Zagreb, Kišpatićeva 12, Zagreb, Croatia.
Journal of Electrocardiology
|February 17, 2026
Summary
Postoperative junctional ectopic tachycardia (JET) in neonates can present with varied ECG findings and cause instability. Early identification and tailored treatment are crucial for managing this rare heart rhythm disorder.
Area of Science:
- Pediatric Cardiology
- Cardiac Electrophysiology
- Neonatal Critical Care
Background:
- Junctional ectopic tachycardia (JET) is a rare but significant arrhythmia in infants and children.
- It often occurs post-congenital heart surgery or is congenital.
- Postoperative JET can lead to hemodynamic instability.
Purpose of the Study:
- To report a case of postoperative JET in a neonate following an arterial switch operation.
- To describe the variable electrocardiographic (ECG) manifestations, including QRS morphologies.
- To emphasize the correlation between intervals and the need for prompt management.
Main Methods:
- Case report of a neonate with postoperative JET.
- Electrocardiographic analysis of variable QRS morphologies.
- Correlation of QP interval and QRS duration with preceding RR interval.
Main Results:
- The neonate developed postoperative JET with variable QRS morphologies after arterial switch.
- QP interval and QRS duration showed correlation with the preceding RR interval.
- The arrhythmia resulted in hemodynamic instability requiring intervention.
Conclusions:
- Postoperative JET in neonates can exhibit diverse ECG presentations.
- Early rhythm characterization is vital for effective, mechanism-based management.
- Prompt antiarrhythmic therapy and supportive care are essential for critically ill neonates.
Keywords:
Antiarrhythmic therapyCongenital heart diseaseElectrocardiographyQRS complexQRS variabilityMore Related Videos
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