Ivabradine is an effective antiarrhythmic therapy for congenital junctional ectopic tachycardia-induced cardiomyopathy during infancy: Case studies.

Junctional ectopic tachycardia (JET) is a rare form of arrhythmia that is most commonly seen during infancy. JET is continuous and incessant, characterized by persistently high heart rates that may result in impaired cardiac function and tachycardia-induced cardiomyopathy. Despite the availability of multiple antiarrhythmic treatments, including flecainide and amiodarone, management of JET is generally very difficult. Catheter ablation has a high risk of atrioventricular block and it may require the placement of a pacemaker. Ivabradine, also known as a cardiac pacemaker cell inhibitor, is a new-generation antiarrhythmic used to treat sinus tachycardia and angina pectoris in adult patients. In this article, we present three cases of subjects with infantile congenital JET who were admitted to our clinic with a tachycardia-induced cardiomyopathy. The age of the subjects ranged from 52 days to 10 months. Although the cases of tachycardia could not be controlled by multiple antiarrhythmics, including a combination of amiodarone and flecainide combined with either propranolol or digoxin, they were rapidly converted into sinus rhythm with an ivabradine treatment of 0.1-0.2 mg/kg/day. No cardiac or other side effects were observed during ivabradine treatment, and left ventricular functions and rhythms improved within 24 hours. These three cases therefore provide hope that ivabradine may be a suitable standard initial treatment for congenital JET. However, additional research is needed to confirm the validity of these results in other circumstances.

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.

Fetal Persistent junctional reciprocating tachycardia : a diagnostic and a therapeutic challenge.

A mother presented with a fetus at 22±1 weeks of gestation with a sustained supraventricular tachycardia  (SVT) at initially 186 beat per minute (bpm). The fetal M-mode echocardiography showed a 1/1 atrio ventricular ratio (with short atrioventricular (AV) interval and a long ventriculo-atrial (VA) interval, suggesting a Persistent junctional reciprocating tachycardia (PJRT) . Upon  initial present no signs of heart failure or hydrops  were noted and treament was initiated with amiodarone and  digoxin . Fetus heart rate slowed  .Postnatal electrocardiogram  Confirmed  the diagnosis of PJRT New born was put on amiodarone and proparonal). Sinus rhythm was rapidly achieved 9 days later .The patient doing well at  10 months of age with maintain of sinus rhythm. Conclusion: our case report illustrates  a particular  form of  JRT   diagnosed  prenatal PJRT  , characterized  by  a good clinical tolerance, its absence of evolution towards cardiomyopathy  and its rapid and unusual response to antiarrhythmics.

Cryoablation of congenital familial ectopic tachycardia with preservation of atrioventricular 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.

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

BACKGROUND: 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. OBJECTIVE: The purpose of this study was to assess the efficacy and safety of adjunctive ivabradine therapy for pediatric congenital JET. METHODS: 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. RESULTS: 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). CONCLUSION: 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.

Efficacy and safety of propafenone in congenital junctional ectopic tachycardia.

OBJECTIVES: Class IC antiarrhythmic drugs have recently been shown to be effective in some patients with atrial ectopic tachycardia. We therefore studied the efficacy of these drugs in patients with congenital junctional ectopic tachycardia. BACKGROUND: Follow-up data on patients with junctional ectopic tachycardia suggest that this potentially lethal arrhythmia may cease spontaneously in a significant proportion of affected children. Therefore, temporary antiarrhythmic treatment appears to be the therapy of choice. METHODS: The efficacy of propafenone was prospectively assessed in four infants with junctional ectopic tachycardia (ventricular rate 180, 185, 210 and 320 beats/min, respectively). The diagnosis of junctional ectopic tachycardia was established before the age of 2 months in all four infants. Propafenone was given orally in a mean dose of 350 (300 to 500) mg/m2 body surface area per day. Success of therapy was determined by serial electrocardiograms (ECGs) and Holter ambulatory ECG monitoring. RESULTS: In two patients, junctional ectopic tachycardia was completely suppressed. In the remaining two patients, the tachycardia rate decreased to less than 150 beats/min. Serum propafenone levels did not correlate with efficacy of treatment. The mean duration of therapy was 18 months (range 3 to 36). No chemical or clinical side effects were noted. CONCLUSIONS: Because of its effectiveness, safety and lack of side effects, propafenone appears to be a valuable drug in the treatment of junctional ectopic tachycardia in newborns and infants.

[Congenital ectopic junctional tachycardia: long-term remission after cryoablation of the bundle of His]. / Taquicardia ectópica congénita de la unión auriculoventricular: remisión a largo plazo tras crioablación del haz de His.

Congenital junctional ectopic tachycardia is an uncommon and potentially fatal arrhythmia that does not usually respond to medical therapy. We report a two month old infant with severe ventricular failure. The diagnosis was confirmed by electrophysiologic study. She underwent endocardial cryoablation of the His bundle during extracorporeal circulation and a ventricle epicardial-lead pacemaker was implanted. Eight years later the patient is still symptom-free without needing medical treatment.

[Ectopic junctional tachycardia of the neonate]. / Tachycardie jonctionnelle ectopique du nouveau-né. A propos de 2 cas.

Congenital ectopic junctional tachycardia (EJT) is a rare arrhythmia presenting in the first 6 months of life. It is often resistant to antiarrhythmic drugs and its poor prognosis (35% mortality) explains its often complex management. The authors report two cases which illustrate its unpredictability with a potential to degenerate to serious ventricular arrhythmias. The possibility of progression to atrioventricular block, increased by antiarrhythmic therapy, may lead to implantation of a cardiac pacemaker. The poor outcome of the two babies underlines the severity of these arrhythmias.

[Cryoenergy for the ablation of arrhythmogenic paraseptal substrates in children and adolescents with heart rhythm disorders]. / Kryoenergie zur Ablation arrhythmogener paraseptaler Substrate bei Herzrhythmusstörungen im Kindes- und Jugendalter.

BACKGROUND AND OBJECTIVE: Cryoablation is safe for the ablation of substrates in proximity to the AV node, because the initial lesion is reversible. We report our results of cryoablation in a transregional center for ablation in children and adolescents. PATIENTS AND METHODS: Data on 39 children and adolescents (4 - 18 years of age) who had been treated with cryo energy were analyzed retrospectively. The diagnosis was AV nodal reentry tachycardia (AVNRT; n = 30), para-Hisian accessory pathway (AP; n = 6) and congenital junctional ectopic tachycardia (JET; n = 4). In addition to non-inducibility, the targeted endpoint for AP-ablation was a missing or decremental concentric retrograde conduction, for ablation of AVNRT the endpoint was no slow pathway, no AH jumps and no echo-beats. The median follow-up was 3 years (270 - 1919 days). RESULTS: The targeted endpoint was reached in 35/39 patients (90 %), in four patients (10 %) RF energy had to be applied. A recurrence occurred in 7/35 (20 %) successfully treated patients. Two patients had a pre-excitation again after AP ablation, but no symptoms. Thus, 28/35 patients (80 %) remained asymptomatic after cryoablation, and 26/35 (74 %) are definitively cured, regarding all follow-up data. The subgroup of AVNRT patients does not differ from the entire group. There was no AV block in the cryoablation group. CONCLUSIONS: Cryoablation is very safe and effective for the definitive treatment of arrhythmias in children and adolescents. The price for the high safety is a reduced efficacy and a higher recurrence rate.

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

PURPOSE OF REVIEW: 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. RECENT FINDINGS: 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. SUMMARY: 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.

A case of congenital junctional ectopic tachycardia: 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.

Successful transcatheter ablation of congenital junctional ectopic tachycardia in a ten-month-old infant using radiofrequency energy.

Congenital junctional tachycardia is a difficult-to-control rhythm in children which has a high mortality rate with current management. A 10-month-old child followed since birth with the diagnosis of congenital junctional ectopic tachycardia is reported. He failed treatment with multiple antiarrhythmic agents, and underwent an electrophysiology study. The junctional focus was successfully ablated using transcatheter radiofrequency energy. This technique may be safer than high voltage DC shock ablation, particularly in small children.

Transcatheter radiofrequency ablation for congenital junctional ectopic tachycardia in infancy.

Congenital junctional ectopic tachycardia (JET) is a difficult to treat arrhythmia with a variably poor response to pharmacologic intervention. We report on the successful treatment of a 17-day-old infant with JET via transcatheter radiofrequency ablation of the arrhythmogenic focus resulting in resolution of the tachycardia and maintenance of normal atrioventricular nodal function. Transcatheter radiofrequency ablation techniques should be considered in infants with life-threatening arrhythmia recalcitrant to standard forms of drug therapy.

Successful radiofrequency catheter ablation of congenital junctional ectopic tachycardia with preservation of atrioventricular conduction in a 9-month-old infant.

An infant with congenital junctional ectopic tachyardia required frequent hospitalizations due to tachycardia acceleration despite multiple antiarrhythmic medications. At 9 months of age, he underwent successful radiofrequency catheter ablation of the tachycardia with preservation of AV conduction.

[Congenital atrioventricular junction tachycardia. Favorable response to anti-arrhythmia agents]. / Taquicardia congénita de la unión A-V. respuesta favorable a los antiarrítmicos.

The congenital junctional ectopic tachycardia, is an unusual tachyarrhythmia, with early clinic manifestation and poor antiarrhythmic drugs response with a great infant mortality reaching rates of 35%. It deserves a special attention in its timely detection as well as in its appropriate handling with different modalities of pharmacological and nonpharmacological therapy. We reported two cases in which age of presentation of tachyarrhythmia was at three months and whose particularity was the good response to antiarrhythmic drugs; verapamil and later propafenone, used for the acute stages and a combination of propafenone plus propranolol initially for the chronic stage. Due to intolerance it was necessary to change the treatment after a year for sotalol and digital with good response. We review the literature about this topic.

Evolving concepts in the management of congenital junctional ectopic tachycardia. A multicenter study.

We reviewed the records of 26 infants with congenital junctional ectopic tachycardia (JET) from seven institutions to examine the evolution in the management of this tachycardia that is difficult to treat. JET was defined electrocardiographically as an incessant tachycardia with normal QRS morphology and atrioventricular (AV) dissociation. The ventricular rate ranged from 140 to 370 beats/min (mean, 230 beats/min); 16 of 26 patients had cardiac failure. Treatment success was defined as a stable decrease in the rate of JET, below 150 beats/min; partial success was a significant decrease of JET rate with alleviation of symptoms. All patients received digoxin with no significant effect. Propranolol was given to 16 patients, with two successes and one partial success. Combinations of other conventional agents were used in 11 patients with two successes; 14 patients were treated with amiodarone, which resulted in eight successes and three partial successes; three patients died suddenly on medical treatment (amiodarone, one patient; propranolol, one patient; or amiodarone plus propranolol, one patient); sudden AV block was a possible cause and consequently, two later patients had pacemaker implantation as well as medical treatment. His catheter ablation was successfully performed twice but contributed to death in a newborn; three surgical His ablations were performed for intractable JET with two successes and one death. The overall mortality was 35%. Among survivors, treatment has been stopped without any complications in five patients ranging in age from 10 months to 8 years (mean, 3.5 years). It seems that amiodarone alone is the best drug for treatment of congenital JET; necessity for permanent pacing remains unsettled. His ablation should be reserved only for intractable JET.