Congenital Junctional Ectopic Tachycardia Research Articles

Reduced kinase function in two ultra-rare TNNI3K variants in families with congenital junctional ectopic tachycardia.

Genetic missense variants in TNNI3K, encoding troponin-I interacting kinase, have been associated with dilated cardiomyopathy (DCM) and observed in families with supraventricular tachycardias (SVT). Previously, a family harboring the TNNI3K-c.1615A > G (p.Thr539Ala) variant presented with congenital junctional ectopic tachycardia (CJET), an arrhythmia that arises from the atrioventricular (AV) node and His bundle. However, this was a relatively small four-generational family with limited genetic testing (N = 3). We here describe a multigenerational family with CJET harboring a novel ultra-rare TNNI3K variant: TNNI3K-c.1729C > T (p.Leu577Phe). Of all 18 variant carriers, 13 individuals presented with CJET, resulting in a genetic penetrance of 72%. In addition, CJET is reported in another small family harboring TNNI3K-c.2225C > T (p.Pro742Leu). Similar to the previously published CJET family, both TNNI3K variants demonstrate a substantial reduction of kinase activity. Our study contributes novel evidence supporting the involvement of TNNI3K genetic variants as significant contributors to CJET, shedding light on potential mechanisms underlying this cardiac arrhythmia.

Ivabradine for congenital ectopic tachycardia in newborn.

Congenital junctional ectopic tachycardia is a rare arrhythmia that occurs in patients without previous cardiac surgery. In this report, we wanted to present a 6-hour-old newborn with congenital junctional ectopic tachycardia resistant to conventional anti-arrhythmic medications, who was successfully treated with ivabradine and amiadarone combination. A six-hour-old newborn girl was hospitalised in neonatal ICU because transient tachypnoea of the newborn. She was tachycardic, and supraventricular tachycardia was noticed. There was no answer to the adenosine esmolol treatment; even synchronised direct cardioversion intravenous amiodarone was started. Junctional ectopic tachycardia was diagnosed. We have added propranolol to the treatment and followed patient for 2 days. On the fourth day, junctional ectopic tachycardia rhythm still persisted; therefore, ivabradine treatment was added to the treatment. On the following day, the heart rhythm was slowed to 110/min, and propranolol was stopped; intravenous amiodarone treatment was changed to the oral form. The rhythm turned into sinus; two days after starting ivabradine and oral amiodarone. Tachyarrhythmia originating in the atrioventricular node and atrioventricular junction including the bundle of His complex are junctional ectopic tachycardia. Congenital junctional ectopic tachycardia is rare, and it is mostly resistant to the conventional treatment.Ivabradine is a new anti-arrhythmic agent, used extensively to decrease sinus rate in the treatment of cardiac failure. Ivabradine may be an option for the resistant congenital ectopic tachycardia.

Congenital Junctional Ectopic Tachycardia in a 6-month-old boy treated with Ivabradine: A Case Report

Congenital junctional ectopic tachycardia (JET) is a rare tachyarrhythmia found in young infants and is often difficult to treat. JET is characterized by incessant tachycardia which causes ventricular dysfunction, heart failure and high mortality. Ivabradine is one of the newer antiarrhythmic drugs with special indications in decreasing heart rate in adults with chronic heart failure. It has shown promising role in congenital JET. However, there are no guidelines recommending ivabradine as a first-line agent for congenital JET. We report an infant with congenital JET who was successfully treated with ivabradine.

Congenital junctional ectopic tachycardia in the paediatric emergency department.

Congenital junctional ectopic tachycardia is a rare but serious cardiac arrhythmia seen in neonates and young infants. It is frequently resistant and refractory to first-line treatment options such as cardioversion with adenosine and direct current shock, and it carries a high morbidity and mortality rate. The aim of this article is to present the case of congenital junctional ectopic tachycardia observed in a 14-day-old neonate, highlighting the role of ivabradine in the management, followed by a discussion about current approaches to treatment.

Interest of ivabradine in pediatric arrhythmia. About a case and review of the literature

By inhibiting the pacemaker current if of the sinoatrial node (SN), ivabradine was first use as an alternative to betablockers in the treatment of heart failure [1] . For a few years, it has been proposed as an adjuvant therapy for postoperative [2] or congenital junctional ectopic tachycardia [3] . But ivabradine can also be effective on atrial and ventricular abnormal automaticity [4] . We report the case of a 9 years old girl who was diagnosed of polymorphic atrial tachycardia at birth. The child was first treated by amiodarone. When amiodarone had to be withdraw because of thyroid dysfunction, multiple antiarrhythmic drugs were tested alone or in association: betablockers, flecainide, digoxine. Despite medication, the child experimented multiple high rate non-sustained tachycardia per day. After an antiarrhythmic washout, ivabradine was started. Fig. 1 is the patient Holter without any treatment showing a very anarchic rhythm, mostly rapid arrhythmia. Fig. 2 is the patient Holter after only 2 takes of ivabradine that shows a marked efficacy of the drug. Ivabradine inhibits selectively the If current that is responsible of the pacemaker activity of the SN and the AV node. If current can also be responsible of abnormal automaticity of the atrial and ventricular myocardium. In such case, ivabradine is highly effective to control the arrhythmia. Still, ivabradine efficacy is difficult to predict, but regarding its overall safety, it can be tested. In a randomized, double-blind trial of pediatric patient with dilated cardiomyopathy, Bonnet et al. did not report more adverse event with ivabradine than with placebo [5] . The outcome of atrial ectopic arrhythmia in the pediatric population is good: 78% will resolve spontaneously when diagnosed under 3 years old [6] . Ivabradine could be an alternative to catheter ablation in the very young or in pediatric patient with multifocal arrhythmia or organized arrhythmia close to the AV conduction system.

Ivabradine Monotherapy for the Treatment of Congenital Junctional Ectopic Tachycardia in a Premature Neonate.

Congenital junctional ectopic tachycardia is a rare and special type of supraventricular arrhythmia. Junctional ectopic tachycardia is characterized by persistently elevated heart rates that may cause an impairment in cardiac function. Junctional ectopic tachycardia is considered one of the most difficult-to-treat conditions even with a combination of antiarrhythmic medications. Ivabradine is a novel antiarrhythmic medication used to decrease the heart rate in adults with angina pectoris. We report a first case of a premature neonate with a normal heart structure who developed junctional ectopic tachycardia and was subsequently treated successfully with ivabradine.

Junctional ectopic tachycardia in infants and children.

Tachyarrhythmias originating in the atrioventricular (AV) node and AV junction including the bundle of His complex (BH) are called junctional tachycardia (JT) or junctional ectopic tachycardia (JET). Congenital JET (CJET) is a rare arrhythmia that occurs in patients without a preceding cardiac surgery and can be refractory to medical therapy and associated with high morbidity and mortality. CJET has a high rate of morbidity and mortality with death occurring in 35% of cases. JET occurring within 72 hours after cardiac surgery is referred to as postoperative JET (POJET) and caused by direct trauma, ischemic, or stretch injury to the AV conduction tissues during surgical repair of congenital heart defects. Focal junctional tachycardia (FJT) is also known as automatic junctional tachycardia and includes paroxysmal or non‐paroxysmal forms. We discuss a staged approach to therapy with improved pharmacological therapies and the use of catheter‐based therapies.

Congenital Junctional Ectopic Tachycardia: There May Be a Light at the End of the Tunnel

Congenital Junctional Ectopic Tachycardia: There May Be a Light at the End of the Tunnel

Long-term Spontaneous Remission of Congenital Junctional Ectopic Tachycardia

Long-term Spontaneous Remission of Congenital Junctional Ectopic Tachycardia

Long-term Spontaneous Remission of Congenital Junctional Ectopic Tachycardia

RESUMEN Introduccion: La taquicardia ectopica de la union (JET) congenita, es una taquicardia supraventricular poco frecuente con alta morbimortalidad. Su tratamiento requiere frecuentemente la asociacion de multiples farmacos durante periodos prolongados de tiempo, necesitando en algunos casos realizar procedimiento invasivo como la crioablacion. Algunos estudios han demostrados la existencia de casos con remision espontanea de la arritmia a largo plazo. (reversion a ritmo sinusal o a un ritmo nodal acelerado sin requerimiento de farmacos y sin mediar intervencion alguna). Objetivos: Evaluar la incidencia de remision espontanea del JET congenito en una poblacion pediatrica en el seguimiento a largo plazo. Material y metodos: Se incluyeron 23 pacientes consecutivos con JET congenito evaluados en el Hospital J.P.Garrahan y en el Hospital Italiano de Buenos Aires entre los anos 1999 y 2017, con un seguimiento medio de 8,8 anos (RIC: 5,5-14,1). Se evaluo a largo plazo la incidencia de remision espontanea de la arritmia. Se definio como remision espontanea a la ausencia de JET en 2 estudios de HOLTER de 24 hs consecutivos separados por 6 meses, y/o a la presencia de ritmo nodal acelerado con frecuencias cardiacas por debajo del percentilo 95 para la edad en ausencia de sintoma, sin necesidad de tratamiento farmacologico o invasivo. Resultados: La mediana para la edad de presentacion fue 2 meses (RIC: 0.625-3), 15 p (62,5%) presentaron signos de insuficiencia cardiaca, 11 p (45,8%) taquicardiomiocardiopatia. La tasa de remision espontanea fue del 52%. A los 4 anos de seguimiento, el 15% de 20 p presentaron remision espontanea, mientras que de los 15 p que alcanzaron los 10 anos de seguimiento el 62,5% presento remision espontanea. La edad media de remision espontanea fue 9,6 anos. Conclusion El JET es una taquicardia potencialmente grave en los primeros meses de vida, pero con alta tasa de remision espontanea a largo plazo.

Ivabradine for congenital junctional ectopic tachycardia in siblings.

Ivabradine for congenital junctional ectopic tachycardia in siblings.

Adjunctive ivabradine in combination with amiodarone: A novel therapy for pediatric congenital junctional ectopic tachycardia

Treatment of congenital junctional ectopic tachycardia (JET) is often challenging. In the majority of patients affected, a combination of ≥2 antiarrhythmic drugs is required for JET control. The purpose of this study was to assess the efficacy and safety of adjunctive ivabradine therapy for pediatric congenital JET. Since January 2015, 5 consecutive patients aged 10 days to 3.5 years (median 8 weeks) were treated with adjunctive ivabradine for congenital JET. All patients had previously undergone antiarrhythmic therapy with unsatisfactory control of JET. Ivabradine was administered orally at an initial dosage of 0.05-0.1 mg/kg/d divided into 2 single doses and was increased up to 0.28 mg/kg/d if necessary. In all 5 patients, ivabradine proved to be successful in controlling JET. Complete suppression of JET and conversion into sinus rhythm were achieved in 4 of 5 patients. The remaining patient had effective heart rate control with persistent slow JET. Mean heart rate was reduced by 31% compared to pre-ivabradine (P = .03) as assessed by 24-hour Holter monitoring. Echocardiography revealed improvement of left ventricular function in all 3 patients with previously impaired left ventricular function. No significant side effects of ivabradine were encountered during median follow-up of 135 days (range 37-203 days). In our group of patients with congenital JET, adjunctive treatment with ivabradine resulted in effective and safe rhythm/heart rate control and therefore may be recommended early in the course of this rare inborn tachyarrhythmia.

Whole exome sequencing identifies the TNNI3K gene as a cause of familial conduction system disease and congenital junctional ectopic tachycardia

We report familial cardiac conduction disease (FCCD) in a 3-generation pedigree, including some family members with congenital junctional ectopic tachycardia (JET) (Fig. 1A). The proband presented during a febrile illness at 3.5-years of age with variable atrio-ventricular (AV) block (1st, 2nd, and 3rd degrees) together with left anterior fascicular block (LAFB) and right bundle branch block (RBBB) (Fig. 1B). Viral studies and echocardiogram were normal and he received a pacemaker; he subsequently developed clinical junctional tachycardia. Family history revealed a maternal grandmother with RBBB diagnosed at 5 years of age. The electrocardiogram (ECG) from the proband's mother revealed sinus rhythm (SR), 1st degree AV block and a nonspecific intraventricular conduction delay. Clinical genetic testing of SCN5A did not reveal any disease-associated mutations. Subsequently she gave birth to identical twin girls. Both girls had rapid JET in the immediate post-natal period that was initially difficult to control. There was rate dependent RBBB and LAFB in both children prior to use of antiarrhythmic drugs. The arrhythmia has resolved in one twin but persists in the other as a catecholamine dependent accelerated junctional rhythm/congenital JET that is modified by propranolol therapy (Fig. 1C). The resting ECGs now both show LAFB and intermittent incomplete RBBB. The mother has subsequently developed symptomatic palpitations and shows electrocardiographic features consistent with typical atrioventricular nodal re-entrant tachycardia (AVNRT) on symptom-rhythm correlation observed on loop recorder. Thus, the conduction defects in this family were of varying severity and the relationship to congenital JET in the three children is important as it is well recognized that congenital JET may progress to heart block [ 1 Henneveld H. Hutter P. Bink-Boelkens M. et al. Junctional ectopic tachycardia evolving into complete heart block. Heart. 1998; 80: 627-628 Crossref PubMed Scopus (23) Google Scholar , 2 Villain E. Vetter V.L. Garcia J.M. et al. Evolving concepts in the management of congenital junctional ectopic tachycardia. A multicenter study. Circulation. 1990; 81: 1544-1549 Crossref PubMed Scopus (211) Google Scholar ]. At this stage the conduction abnormalities are minor in the twins who presented with the JET and have not progressed.

Potential New Indication for Ivabradine: Treatment of a Patient with Congenital Junctional Ectopic Tachycardia

Ivabradine is a new antiarrhythmic agent with direct inhibition of the pacemaker (If) current. It has been used extensively to decrease sinus rate in the treatment of cardiac failure, and also in a single case of atrial ectopic tachycardia in a child. Here we report the case of a 3-year-old girl with congenital junctional ectopic tachycardia (JET), resistant to conventional antiarrhythmic medications, who was successfully treated with ivabradine. We suggest that ivabradine can be an effective treatment for junctional automatic tachycardias and can be considered as a new line of therapy for this incessant form of tachycardia.

Short- and Long-Term Outcomes in Children Undergoing Radiofrequency Catheter Ablation Before Their Second Birthday

Background Tachyarrhythmias can cause substantial morbidity and mortality in infants and very young children. Our objective was to assess early and late outcomes in children undergoing radiofrequency catheter ablation before their second birthday. Methods This is a retrospective review of medical records from 1995 till 2009 at a single institution with a large referral base. Results Thirty-four children younger than 2 years of age were brought to the electrophysiology laboratory for catheter ablation for tachyarrhythmia. Radiofrequency ablation (42 procedures) was performed in 31 children (mean weight, 7.4 kg; range, 2.6-12.3 kg). Tachyarrhythmias were atrioventricular re-entry tachycardia (19), ectopic or multifocal atrial tachycardia (6), atrial flutter (1), ventricular tachycardia (3), and congenital junctional ectopic tachycardia (2). Seventeen children presented with tachycardia-induced cardiomyopathy and heart failure. Three patients required extracorporeal life support prior to the procedure. Radiofrequency catheter ablation was successful in 74% of these very young children vs 91% in a comparison group of children older than 2 years (n = 447). Among patients with initially successful ablations, there was no tachyarrhythmia recurrence during medium- to long-term follow-up (1.4-15.0 years; mean, 7.3 years). Major complications occurred in 4 very young children. Eight of 11 patients in whom ablation failed or could not be done required another form of continued aggressive treatment. Conclusion Catheter ablation is indicated and successful in critically ill infants with life-threatening tachyarrhythmia refractory to medical therapy. Initially successful procedures are associated with excellent long-term outcomes, but significant complication rates require that such procedures be reserved for carefully selected patients and performed by highly skilled staff.

Case report: an infant with congenital junctional ectopic tachycardia requiring extracorporeal mechanical oxygenation

A case report of an infant with hemodynamic compromise and impending collapse due to congenital junctional ectopic tachycardia. Medical therapy was maximized and he required the rapid initiation of extracorporeal life support, in order to achieve hemodynamic stability. This case report briefly reviews the presentation and treatment options for congenital junctional ectopic tachycardia, as well as the indications for initiation of mechanical support for this potentially lethal condition. Congenital junctional ectopic tachycardia is a rare though often fatal arrhythmia of the newborn or infant. Medical treatment options may be limited, or may require time to attain efficacy. Despite aggressive escalation of antiarrhythmic therapy, mechanical support in the form of extracorporeal mechanical oxygenation is a viable option, until the arrhythmia is well controlled and the myocardium recovers function.

Cryoablation of Congenital Familial Ectopic Tachycardia with Preservation of Atrioventircular Nodal Function in an Infant

A 1-year-old child weighing 8 kg with familial congenital junctional ectopic tachycardia that was difficult to treat with antiarrhythmic medications underwent successful cryoablation with preservation of atrioventricular (AV) nodal function. This report describes a strategy of cryoablation in conjunction with a 3-D mapping system and the use of atrial overdrive pacing during cryothermal application to assess AV nodal function.

Congenital junctional ectopic tachycardia and congenital complete atrioventricular block: A shared etiology?

t c a U o d Congenital junctional ectopic tachycardia is a rare but erious arrhythmia with onset in infancy and early childood. Its etiology is poorly understood. Henneveld et al escribed a patient with congenital junctional ectopic tachyardia who subsequently developed complete atrioventriclar block. Histologic studies of congenital junctional ecopic tachycardia suggest an association with fibrosis of the V node. These observations suggest a relationship between conenital junctional ectopic tachycardia and congenital comlete atrioventricular block. Similar to congenital junctional ctopic tachycardia, congenital complete AV block is an rrhythmia of infancy and is associated with extensive firosis of the AV node. In children with structurally normal hearts, congenital omplete AV block is most commonly associated with maernal connective tissue disease, manifested by the presence f maternal anti-SSA and anti-SSB antibodies. Studies in nimals and in humans suggest anti-SSA and anti-SSB ntibodies have a direct effect on the conduction system in etuses and neonates. We hypothesized that congenital junctional ectopic achycardia is caused by anti-SSA and anti-SSB antibodies. n this report, we present evidence from three families in upport of this hypothesis. Two families were diagnosed ostnatally, whereas one child was diagnosed in utero using etal magnetocardiography. Congenital junctional ectopic achycardia was diagnosed by ECG or fetal magnetocardioraphy when a narrow QRS complex tachycardia with AV issociation and an atrial rate slower than the ventricular ate was seen. Patients and their mothers were tested for nti-SSA and anti-SSB antibodies by enzyme-linked immuosorbent assay at commercial laboratories (Associated Reional and University Pathologists, SmithKline Beecham,

A Case of Congenital Junctional Ectopic Tachycardia: Prenatal Diagnosis and Successful Radiofrequency Catheter Ablation in Infancy

It is difficult to make a definitive diagnosis of congenital junctional ectopic tachycardia (JET) in utero. We report a case in which congenial JET was suspected by fetal M-mode echocardiography. Fetal M-mode tracing of the atria and ventricle clearly showed a gradual acceleration of ventricular activity at the beginning of tachycardia, the warming-up sign of ectopic tachycardia, which was followed by simultaneous contractions of atrium and ventricle. This report also describes successful emergent radiofrequency catheter ablation of congenital JET in infancy with preservation of normal AV nodal conduction for this patient.

Atrial Pacing During Radiofrequency Ablation of Junctional Ectopic Tachycardia

Radiofrequency catheter ablation (RFCA) was performed on a 5-year-old boy with congenital junctional ectopic tachycardia (JET) that was refractory to medical management. Because of the lack of retrograde atrial depolarization during tachycardia, radiofrequency energy was delivered during atrial overdrive pacing to confirm the presence of preserved atrioventricular (AV) conduction. Although the procedure was complicated by complete right bundle branch block after ablation of the para-Hissian region, the patient regained sinus rhythm accompanied by normal AV conduction. Rapid atrial pacing during RFCA of JET may be safely used to avoid AV block.