Overview
Junctional ectopic tachycardia (JET) is a rare arrhythmia characterized by atrioventricular dissociation and a high junctional escape rhythm, often complicating post-surgical states or presenting in neonates 14.Diagnosis
Electrocardiogram (ECG) findings: Atrioventricular dissociation, high junctional escape rhythm 14.
Fetal diagnosis: Possible through prenatal echocardiography, though challenging 24.
Echocardiography: Essential for assessing cardiac function and structure 4.Management
First-line treatments:
- Atrial pacing: R-wave synchronized atrial pacing, including transoesophageal pacing when conventional methods fail 1.
- Antiarrhythmic drugs: Propafenone (mean dose 350 mg/m2/day) for congenital cases 6.
Adjunctive treatments:
- Therapeutic hypothermia: Effective in reducing heart rate and improving cardiac output in post-surgical cases 37.
- Catheter ablation: Guided low-dose radiofrequency energy application near the His-bundle area 5.
- Transplacental therapy: Use of digoxin and sotalol in fetal cases 2.Special Populations
Pregnancy: Prenatal diagnosis and transplacental therapy with drugs like digoxin and sotalol may be considered 2.
Pediatrics: Therapeutic hypothermia and antiarrhythmic drugs like propafenone are effective 367.
Comorbidities: Dilated cardiomyopathy may coexist, requiring careful monitoring and adjunctive treatments like catheter ablation 5.Key Recommendations
Use therapeutic hypothermia for post-surgical JET with heart rates >200 bpm to control rate and prevent cardiac failure (Evidence: Strong 37).
Consider atrial pacing, including transoesophageal pacing, as a primary intervention when conventional methods are ineffective (Evidence: Moderate 1).
Propafenone can be used as a first-line antiarrhythmic drug in congenital JET with careful monitoring (Evidence: Moderate 6).
Catheter ablation guided by low-dose radiofrequency energy near the His-bundle area may be curative without causing AV block (Evidence: Weak 5).
In prenatal cases, consider transplacental therapy with drugs like digoxin and sotalol for managing fetal JET (Evidence: Expert opinion 2).References
1 Entenmann A, Reineker K, Kramer HH. R-wave synchronised atrial pacing in post-operative junctional ectopic tachycardia using a transoesophageal pacemaker. Cardiology in the young 2013. link
2 Ishikawa K, Kikuchi A, Matsui H, Tamaru S, Imada S, Horikoshi T et al.. Transplacental fetal therapy for junctional ectopic tachycardia. Journal of clinical ultrasound : JCU 2012. link
3 Kelly BP, Gajarski RJ, Ohye RG, Charpie JR. Intravenous induction of therapeutic hypothermia in the management of junctional ectopic tachycardia: a pilot study. Pediatric cardiology 2010. link
4 Lupoglazoff JM, Denjoy I, Luton D, Magnier S, Azancot A. Prenatal diagnosis of a familial form of junctional ectopic tachycardia. Prenatal diagnosis 1999. link1097-0223(199908)19:8<767::aid-pd617>3.0.co;2-1)
5 Wu MH, Lin JL, Chang YC. Catheter ablation of junctional ectopic tachycardia by guarded low dose radiofrequency energy application. Pacing and clinical electrophysiology : PACE 1996. link
6 Paul T, Reimer A, Janousek J, Kallfelz HC. Efficacy and safety of propafenone in congenital junctional ectopic tachycardia. Journal of the American College of Cardiology 1992. link90192-p)
7 Bash SE, Shah JJ, Albers WH, Geiss DM. Hypothermia for the treatment of postsurgical greatly accelerated junctional ectopic tachycardia. Journal of the American College of Cardiology 1987. link80351-0)