Junctional ectopic tachycardia (JET)

Abstract

Junctional Ectopic Tachycardia (JET) is a tachyarrhythmia arising from the atrioventricular node and His bundle area. It is also called junctional tachycardia, focal junctional tachycardia, or junctional nonreentrant tachycardia. Heart rate in JET should be more than 95 th percentile of heart rate for age (typically more than 100 beats per minute in adults); otherwise, it is called accelerated junctional rhythm. 1-3 JET is more common in children and may be congenital or acquired in postoperative settings. JET is a rare arrhythmia in adults and the pathogenesis is not completely understood. Moreover, because its clinical and electrocardiographic presentation varies, the diagnosis is challenging, and it can be easily mistaken for more common arrhythmias like atrioventricular nodal reentrant tachycardia (AVNRT). 1,4-5 2 | CLINI C AL FE ATURE S This arrhythmia can be categorized as primary JET, without a clear predisposing factor, or secondary JET, which occurs in a clinical condition. Primary JET occurs as congenital form or as sporadic cases in children and adults. Congenital JET occurs within the first 6 months of age, usually presents at birth, and is associated with high morbidity and mortality. It is an arrhythmia with mean ventricular rates of 200 to 250 beats/min and is associated with a high incidence of ventricular systolic dysfunction and clinical heart failure. Prenatal cases may present with hydrops. 1 When it occurs after the age of 6 months, the clinical course is not malignant. Indeed, a similar clinical course to other supraventricular tachycardias has been reported in adults and the main symptom in these patients is palpitations with exacerbation during physical

Cold collision: A novel cryothermal ablation technique for junctional ectopic tachycardia

“…The idiopathic form of JET is often resistant to antiarrhythmic drug therapy and radiofrequency ablation is associated with a high risk of unintentional AV nodal block. 1 , 2 , 3 , 4 , 8 We previously reported the largest study to date analyzing the location of the JET focus using 3D mapping and cryothermal ablation and thereafter described the procedural technique. 2 , 7 In this case report we demonstrated that the ectopic focus may be located at the lower part of the triangle of Koch, close to the slow pathway area, and either cryoablation or a careful radiofrequency lesion may be successful.…”

“…The idiopathic form of JET in a structurally normal heart is rare and often resistant to antiarrhythmic drug therapy. 1 , 2 , 3 , 4 Transcatheter radiofrequency ablation has been reported for use of treatment for JET but is associated with a high risk of inadvertent AV nodal block. 3 As a result, utilization of 3-dimensional (3D) mapping, atrial overdrive pacing, and cryoablation have been developed for ectopic focus localization, arrhythmia identification, and ablation of the junctional ectopic foci, respectively.…”

Acute myocarditis presenting as accelerated junctional rhythm in Graves’ disease: A case report

“…Junctional tachycardia is also known as junctional ectopic tachycardia (JET), and the mechanism thereof is the same as accelerated junctional rhythm. Junctional tachycardia is thought to arise from the atrioventricular node and the His bundle area[ 12 ]. The incessant form of junctional ectopic tachycardia with 1:1 ventriculoatrial conduction, is a regular, short RP, narrow complex tachycardia and similar to typical Atrial Ventricular Nodal Reentry Tachycardia[ 12 ].…”

“…Junctional tachycardia is thought to arise from the atrioventricular node and the His bundle area[ 12 ]. The incessant form of junctional ectopic tachycardia with 1:1 ventriculoatrial conduction, is a regular, short RP, narrow complex tachycardia and similar to typical Atrial Ventricular Nodal Reentry Tachycardia[ 12 ]. The patient’s electrocardiography findings were consistent with an accelerated junctional rhythm, which is rarely seen in children with acute viral myocarditis and even rarer in adults.…”

An adult case of junctional tachycardia diagnosed by premature atrial contractions and atrial overdrive pacing

“…During right ventricular overdrive pacing (RVOP), an atrial activation sequence was identical to the NCT. The difference between the post‐pacing interval and tachycardia cycle length corrected by an atrioventricular nodal conduction delay was 136 ms (>110 ms) with a V‐A‐V response after RVOP, which was less likely to be an atrioventricular reentry tachycardia or atrial tachycardia 3,4 . A spontaneous early PAC advanced the His potential immediately, and the tachycardia was still sustained (Figure 3A).…”