Uso de la ivrabadina para el tratamiento de la taquicardia ectópica de la unión congénita / Use of ivabradine for the treatment of congenital junctional ectopic tachycardia

Resumen La taquicardia ectópica de la unión en su variante congénita es una taquiarritmia pediátrica poco frecuente, que por su naturaleza incesante y su refractariedad a los agentes farmacológicos tradicio nales lleva asociada una alta morbimortalidad. Se presentan los casos clínicos de dos pacientes pediátricos con diagnóstico de taquicardia ectópica de la unión congénita, que mostraron respuesta inadecuada a las alternativas de tratamiento habituales y que, en consecuencia, desarrollaron miocardiopatía dilatada y disfunción ventricular secundaria a la taquicardia sostenida. En ambos se utilizó ivabradina como alternativa farmacológica innovadora pare el control de ésta con excelente respuesta clínica.

Abstract The congenial form of junctional ectopic tachycardia is a rare variant of pediatric tachyarrhythmia that due to its incessant nature and its refractoriness to the traditionally used antiarrhythmic agents has a high morbimortality The clinical cases of two patients with a diagnosis of congenital junctional ectopic tachycardia with inadequate response to the regular pharmacological options, who developed dilated cardiomyopathy and ventricular dysfunc tion secondary to sustained tachycardia, are presented. In both ivrabadine, a new innovative option was used with excellent clinical response.

Effect of dexmeditomidine on postoperative junctional ectopic tachycardia after complete surgical repair of tetralogy of Fallot: A prospective randomized controlled study.

Introduction: Incidence of junctional ectopic tachycardia (JET) after repair of tetralogy of Fallot (TOF) is 5.6–14%. Dexmeditomidine is a α-2 adrenoceptor agonist modulates the release of catecholamine, resulting in bradycardia and hypotension. These effects are being explored as a therapeutic option for the prevention of perioperative tachyarrhythmia. We undertook this study to examine possible preventive effects of dexmedetomidine on postoperative JET and its impact on the duration of ventilation time and length of Intensive Care Unit stay. Methods: After obtaining approval from the hospitals ethics committee and written informed consent from parents, this quasi-randomized trial was initiated. Of 94 patients, 47 patients received dexmedetomidine (dexmedetomidine group) and 47 patients did not receive the drug (control group). Results: Dexmedetomidine group had more number of complex variants like TOF with an absent pulmonary valve or pulmonary atresia (P = 0.041). Hematocrit on cardiopulmonary bypass (CPB), heart rate while coming off from CPB and inotrope score was significantly low in the dexmedetomidine group compared to control group. The incidence of JET was significantly low in dexmedetomidine group (P = 0.040) compared to control group. Conclusions: Dexmedetomidine may have a potential benefit of preventing perioperative JET.

Predictors of Intensive Care Unit Morbidity and Midterm Follow-up after Primary Repair of Tetralogy of Fallot

BACKGROUND: Fallot (TOF) repair, and identify predictors of intensive care unit (ICU) morbidity. METHODS: We analyzed perioperative and midterm follow-up data for all cases of primary TOF repair from 2001 to 2012. The primary endpoint was early mortality and morbidity, and the secondary endpoint was survival and functional status at follow-up. RESULTS: Ninety-seven patients underwent primary repair. The median age was 4.9 months (range, 1 to 9 months), and the median weight was 5.3 kg (range, 3.1 to 9.8 kg). There was no early surgical mortality. The incidence of junctional ectopic tachycardia and persistent complete heart block was 2% and 1%, respectively. The median length of ICU stay was 6 days (range, 2 to 21 days), and the median duration of mechanical ventilation was 19 hours (range, 0 to 136 hours). By multiple regression analysis, age and weight were independent predictors of the length of ICU stay, while the surgical era was an independent predictor of the duration of mechanical ventilation. At the 8-year follow-up, freedom from death and re-intervention was 97% and 90%, respectively. CONCLUSION: Primary TOF repair is a safe procedure with low mortality and morbidity in a medium-sized program with outcomes comparable to national standards. Age and weight at the time of surgery remain significant predictors of morbidity.

QTc Prolongation after Ventricular Septal Defect Repair in Infants

BACKGROUND AND OBJECTIVES: Prolonging of the corrected QT interval (QTc) has been reported after cardiac surgery in some studies. However, there have not been many studies on infant open cardiac surgery for ventricular septal defect (VSD) repair. This study was performed to define the changes in QTc and to find related post-surgery factors in this patient group. SUBJECTS AND METHODS: From 2008 to 2012, 154 infants underwent VSD repair at the Severance Cardiovascular Hospital. This study includes 105 of these cases. QTc was measured in these patients retrospectively. Demographic data and peri-procedural data, such as Aristotle score, cross-clamp time and bypass time, were analyzed. The exclusion criteria included multiple and small VSDs that underwent direct closure. RESULTS: Mean post-operative QTc was increased compared to the pre-operative measurements (from 413.6+/-2.3 to 444.9+/-2.5, p<0.001). In multiple linear regression, the comprehensive Aristotle score was associated with increasing QTc (p=0.047). The incidence of transient arrhythmia, such as atrial tachycardia, junctional ectopic tachycardia, premature atrial contraction, or premature ventricular contraction, was associated with QTc prolongation (p=0.005). Prolonged QTc was also associated with cross-clamp time (p=0.008) and low weight (p=0.042). Total length of stay at the intensive care unit and intubation time after surgery were not associated with QTc prolongation. CONCLUSION: Prolonged QTc could be seen after VSD repair in infants. This phenomenon was associated with peri-procedural factors such as the Aristotle score and cross-clamp time. Patients with QTc prolongation after cardiac surgery had an increased tendency towards arrhythmogenicity in the post-operative period.

Dexmedetomidine controls junctional ectopic tachycardia during Tetralogy of Fallot repair in an infant.

Dexmedetomidine is a highly selective α2 -adrenergic agonist approved for short-term sedation and monitored anesthesia care in adults. Although not approved for use in the pediatric population, an increasing number of reports describe its use in pediatric patients during the intraoperative period and in the intensive care unit. Dexmedetomidine can potentially have an adverse impact on the cardiovascular system secondary to its negative chronotropic and dromotropic effects. However, it is these cardiac effects that are currently being explored as a therapeutic option for the treatment of perioperative tachyarrhythmias in pediatric patients with congenital heart disease (CHD). We report the use of dexmedetomidine to treat junctional ectopic tachycardia (JET), which developed following cardiopulmonary bypass for surgical correction of Tetralogy of Fallot in a 6-week-old infant. Within 15 min of increasing the dexmedetomidine infusion from 0.5 to 3 μg/kg/h, JET converted to normal sinus rhythm. This case report provides additional anecdotal evidence that dexmedetomidine may have a therapeutic role in the treatment of perioperative tachyarrhythmias in pediatric patients with CHD. The specific effects of dexmedetomidine on the cardiac conduction system are reviewed followed by a summary of previous reports describing its use as a therapeutic agent to treat perioperative arrhythmias.

Taquicardia ectópica congénita de la unión: Tratamiento farmacológico en el primer año de vida / Congenital junctional ectopic tachycardia: Pharmacologic management during infancy

La forma congénita de la taquicardia ectópica de la unión (TEU) es una arritmia poco frecuente que suele presentar dificultades en su manejo farmacológico, con altas tasas de morbilidad y mortalidad. El objetivo de este trabajo fue informar la experiencia en el seguimiento y el tratamiento de esta forma de taquicardia supraventricular en pacientes menores de un año. Se identificaron siete pacientes con TEU congénita en 28 meses de seguimiento entre 2008 y 2010. El diagnóstico fue realizado en el primer día de vida en cuatro pacientes y dentro de los 150 días de vida en los 3 restantes. Sólo dos presentaron miocardiopatía dilatada. Ninguno presentó cardiopatía estructural. Se utilizó amiodarona en todos los pacientes, en un caso como única droga, asociándose a propanolol en cuatro. En un paciente se asoció flecainida a estos dos fármacos y en otro se la combinó con amiodarona. En un tiempo de seguimiento con un rango de 1-28 meses (media 12.2 meses, mediana 9.75 meses) en tres de los pacientes se consiguió obtener ritmo sinusal alternante con taquicardia nodal lenta; ninguno presentó efectos adversos secundarios a la medicación, ni deterioro de la función ventricular. Hubo sólo una muerte en el grupo estudiado. En conclusión, la combinación de fármacos antiarrítmicos (amiodarona más propranolol y eventualmente flecainida) constituye una alternativa válida para un adecuado control de la TEU congénita en pacientes menores de un año de edad.

Congenital junctional ectopic tachycardia (JET) is a rare arrhythmia that can be refractory to medical therapy with high morbidity and mortality rates. The aim of this study was to report our experience with pharmacologic management of congenital JET in infants. Seven patients with congenital JET were identified between 2008 and 2010. Only two of them presented dilated cardiomyopathy. There were no congenital structural defects. Amiodarone was given to all the patients, as single therapy in one, and in combination with propranolol in four. In one patient flecainide was administered together with amiodarone and propranolol, and in another patient was used combined with amiodarone. During follow- up with an average time of 12.2 months (median 9.75 months, range 1-28 months), sinus rhythm alternating with slow junctional tachycardia was successfully achieved in 3 patients; no side effects were detected. There was only one death in our study group. The combination of different antiarrhythmics (amiodarone plus propranolol, and eventually flecainide) is a valid option for rhythm control and management of JET in infants.

Early postoperative arrhythmias after open heart surgery of pediatric congenital heart disease / 소아과

PURPOSE: Early postoperative arrhythmias are a major cause of mortality and morbidity after open heart surgery in the pediatric population. We evaluated the incidence and risk factors of early postoperative arrhythmias after surgery of congenital heart disease. METHODS: From January 2002 to December 2008, we retrospectively reviewed the medical records of the 561 patients who underwent cardiac surgery in Kyungpook National University Hospital. We analyzed patients' age and weight, occurrence and type of arrhythmia, cardiopulmonary bypass (CPB) time, aortic cross clamp (ACC) time, and postoperative electrolyte levels. RESULTS: Arrhythmias occurred in 42 of 578 (7.3%) cases of the pediatric cardiac surgery. The most common types of arrhythmia were junctional ectopic tachycardia (JET) and accelerated idioventricular rhythm (AIVR), which occurred in 17 and 13 cases, respectively. The arterial switch operation (ASO) of transposition of the great arteries (TGA) had the highest incidence of arrhythmia (36.4%). Most cases of cardiac arrhythmia showed good response to management. Patients with early postoperative arrhythmias had significantly lower body weight, younger age, and prolonged CPB and ACC times (P<0.05) than patients without arrhythmia. Although the mean duration of ventilator care and intensive care unit stay were significantly longer (P<0.05), the mortality rate was not significantly different among the 2 groups. CONCLUSION: Early postoperative arrhythmias are a major complication after pediatric cardiac surgery; however, aggressive and immediate management can reduce mortality and morbidity.

Arrhythmia in early post cardiac surgery in pediatrics: Siriraj experience.

OBJECTIVES: To determine the incidence, risk factors and outcome of early postoperative arrhythmias in pediatric patients with congenital heart disease. MATERIAL AND METHOD: A prospective study was conducted in every pediatric patient who consecutively underwent open-heart surgery at Siriraj Hospital from January 1st to December 31st, 2006. The collected data were demographic data, diagnosis, pre-operative arrhythmia, cardiac surgical data and continuous electrocardiographic monitoring data throughout the post operative intensive care period. RESULTS: A total of 191 pediatric patients underwent cardiac surgery. Forty-five cases (23.5%) developed early post operative cardiac arrhythmias i.e. junctional ectopic tachycardia 18 cases (40%), heart block 7 cases (15.6%), supraventricular tachycardia 2 cases (4.4%). Cardiac arrhythmia occurred mostly within 24 hours after the operation. Patients with single ventricle physiology repaired developed the highest incidence of acute post operative arrhythmia (36.4%). Longer, cardiopulmonary bypass time- and redo-operation were the risk factors. Thirty-nine cases were treated with medications, 7 cases with temporary pacing, and 1 case with electrical cardioversion. Four patients needed long-term anti-arrhythmic agents. Cardiac arrhythmia played role in the causes of death in 2 cases (1.1% of total cases). CONCLUSIONS: Post operative arrhythmias remained common and important complications of pediatric open-heart surgery. Long cardiopulmonary bypass time and redo-operation were risk factors for early post operative arrhythmia.

Documenting junctional ectopic tachycardia following pediatric open heart surgery.

OBJECTIVE: To determine appropriated documentations for diagnosis junctional ectopic tachycardia (JET) before treatment in post-operative open heart surgery and identify risk factors for post-operative cardiac arrhythmias in children. MATERIAL AND METHOD: The authors performed a retrospective chart review in 277 patients who underwent surgical corrections at British Columbia's Children Hospital from January 1st, 2000 to December 31st, 2001. History, clinical symptoms, complication of surgery and post-operative cardiac arrhythmias were reviewed from medical records. The authors investigated whether JET was being diagnosed accurately and whether it was being adequately documented prior to the initiation of therapy. The authors also identified risk factors that were associated with JET. All documentations before treatment were reviewed by Pediatric cardiologists to confirm diagnosis. RESULTS: Although the diagnostic accuracy (84%), sensitivity (87%), and specificity (84%) are high, a significant number of patients with post-operative arrhythmias were treated without adequate documentation of the arrhythmia. The documentation of arrhythmias in the Intensive Care Unit was largely limited to rhythm strips, with very few 12-lead ECGs and wire studies performed to assist with the diagnosis. CONCLUSION: The presented data indicates that, in this critically-ill population, there was an unacceptable number of patients with post-operative arrhythmias who may have been treated inappropriately. It is very important to emphasize the interpretation of wire studies, an investigation normally done in a critical care setting and whose interpretation is very important to the accurate diagnosis of pediatric arrhythmias.

Reporte de un caso de tauicardia reciprocante de la unión o taquicardia de Coumel

La taquicardia reciprocante de la unión o taquicardia de coumel fue descrita por primera vez hace 30 años. Previamente se consideraba como una taquicardia originada en la aurícula. El substrato anatómico más aceptado involucra una vía accesoria con conducción ventrículo atrial con propiedades decrementales. Es por lo general una tauicardia de personas jóvenes que por ser frecuentemente incesante puede producir taquicardiomiopatía y en el electrocardiograma de superficie se carcteriza por la presencia de ritmo sinusal sin onda delta. tres patologías comparten el patrón electrocardiográfico de taquicardias de complejos estrechos con intervalo RP>PR y onda P negativa en derivaciones inferiores (taquicardia atrial, taquicardia por reentrada intranodal variedad no común y taquicardia reciprocante de la unión). El diagnóstico correcto de la taquicardia tiene consecuencias importantes para el paciente. El presente caso ilustra cómo hacer el diagnóstico diferencial correcto entre estas tres arritmias con la ayuda del estudio electrofisiológico, cómo demostrar las propiedades decrementales de la vía accesoria y cómo un paciente joven refractario al tratamiento farmacológico puede ser curado utilizando ablación con radiofrecuencia, con una mínima morbilidad.

Taquicardia congénita de la unión A-V. Respuesta favorable a los antiarrítmicos / Congenital junctional ectopic tachycardia

La taquicardia congénita de la unión A-V es muy rara, con manifestación clínica temprana, pobre respuesta a los diferentes fármacos antiarrítmicos y con una gran morbimortalidad infantil (mortalidad del 35 por ciento). Merece una especial atención tanto en su oportuna detección como en su adecuado manejo con los diferentes procedimientos terapéuticos farmacológicos y no farmacológicos disponibles actualmente. Nosotros reportamos los casos de dos enfermos cuya edad de presentación de la taquiarritmia fue a los tres meses y cuya peculiaridad fue la buena respuesta a los fármacos antiarrítmicos. El Verapamilo y posteriormente la Propafenona intravenosa se usaron para las etapas agudas y una combinación de Propafenona más propranolol inicialmente para la fase crónica. Por manifestaciones de intolerancia, fue necesario cambiar después de un año tal combinación por Sotalol y Digital, con buena respuesta. Hacemos además una revisión de la literatura disponible hasta el momento sobre esta entidad

Extracorporeal Membrane Oxygenation in the Patient with Cardiopulmonary Resuscitation Failure after Open Heart Surgery: A Case Report / 대한흉부외과학회지

We describe a case of successful extracorporeal membrane oxygenation(ECMO) in a small infant with cardiopulmonary resuscitation(CPR) failure after an open heart surgery. A 35-day-old male infant weighing 4.4 kg who had congestive heart failure and pulmonary hypertension underwent patch closure of ventricular septal defect without any intraoperative event. Postoperative course was unremarkable in the intensive care uint for about 5 hours before the junctional ectopic tachycardia developed. Sudden cardiac decompensation with bradycardia occurred about 50 minutes after the development of junctional ectopic tachycardia. He was put on ECMO by arterial cannulation at the ascending aorta and by venous cannulation at the right atrial appendage after 4 hours' CPR. The hemodynamics were stable with enough urine output during ECMO. He was weaned from ECMO 38.5 hours after initiation. Delayed sternal closure was attempted. He was extubated on postoperative day 7 and discharged home on postoperative day 21 without any neurologic sequelae.

Hypothermia for the Junctional Ectopic Tachycardia after VSD Closure: one case report / 대한흉부외과학회지

50 days old, 4.5kg male patient was admitted at department of pediatrics due to congenital heart disease with congestive heart failure. The echocardiographic finding was perimembranous type ventricular septal defect. The patient underwent open heart surgery for patch closure of VSD. Immediately postoperatively, junctional ectopic tachycardia developed and the patient was in hemodynamically unstable state with decreased urine output. We used inotropics, digitalis and diuretics, however these treatments were not effective in recovering the unstable state. Therefore, we tried a mild hypothermic treatment (34degree C). During the POD #2, mild hypothermia method was repeated four times. The junctional ectopic tachycardia was converted to normal sinus rhythm, hemodynamic state was stable, and urine output was increased. The patient was discharged at POD #8.

Tachycardia Induced Cariomyopathy in Childhood

PURPOSE: Dilated cardiomyopathy in children is usually progressive and leads to death in several years. Chronic tachyarrhythmia has been shown to cause dilated cardiomyopathy in human and animals and this ventricular dysfuntion is usually reversible after control of the arrhythmia. The uncontrolled chronic tachycardia may be a curable cause of dilated cardiomyopathy in some patients. We describe six children who had persistent chronic tachycardia and ventricular dysfunction that improve significantly after control of the arrhythmia. METHODS: We retrosepctively reveiwed the medical records, electrocardiograms, Holter recordings, Echcardiographic reports of 6 children with the tachycardia induced ventricular dysfunction who have been managed at Sejong general hospital and Asan medical center from January 1992 to June 1995. RESULTS: 1) The causes of referral were dilated cardiomyopathy in 2 and tachyarrhythmia in 4. The age at diagnosis was 4 to 36 months old and follow-up period was 6 to 29 months. The symptoms of congestive heart failure were seen in 3 children. 2) The mechanisms of thachyarrhythmia causing cardiomyopathy were atrial ectopic tachycardia in 2, chaotic atrial rhythm in 3 and junctional ectopic tachycardia in 1. Atrial ectopic tachycardia has improved after combined treatment with amidarone and atenonl. One case of chaotic atrial rhythm has improved spontaneously and other 2 cases of chaotic arial rthythm have improved after treatment with digoxin or after combined therapy with amidarone and digoxin. Junctional ectopic tachycardia is partially controlled with mexiletine. 3) The shortening fractions of left ventricle at diagnosis were 14-21% and improved to over 30% in all after 2 to 9 months of follow-up. CONCLUSIONS: We have shown that control of persistent tachycardia resolved the left ventricular dysfunction. We suggest that patients with dilated cardiomyopathy be carefully screened for tachyarrhythmia as a curable cause of ventricular dysfunction and that left ventricular function be assessed in the asymptomatic patients with persistent tachycardia.

Tachycardia Induced Cariomyopathy in Childhood

PURPOSE: Dilated cardiomyopathy in children is usually progressive and leads to death in several years. Chronic tachyarrhythmia has been shown to cause dilated cardiomyopathy in human and animals and this ventricular dysfuntion is usually reversible after control of the arrhythmia. The uncontrolled chronic tachycardia may be a curable cause of dilated cardiomyopathy in some patients. We describe six children who had persistent chronic tachycardia and ventricular dysfunction that improve significantly after control of the arrhythmia. METHODS: We retrosepctively reveiwed the medical records, electrocardiograms, Holter recordings, Echcardiographic reports of 6 children with the tachycardia induced ventricular dysfunction who have been managed at Sejong general hospital and Asan medical center from January 1992 to June 1995. RESULTS: 1) The causes of referral were dilated cardiomyopathy in 2 and tachyarrhythmia in 4. The age at diagnosis was 4 to 36 months old and follow-up period was 6 to 29 months. The symptoms of congestive heart failure were seen in 3 children. 2) The mechanisms of thachyarrhythmia causing cardiomyopathy were atrial ectopic tachycardia in 2, chaotic atrial rhythm in 3 and junctional ectopic tachycardia in 1. Atrial ectopic tachycardia has improved after combined treatment with amidarone and atenonl. One case of chaotic atrial rhythm has improved spontaneously and other 2 cases of chaotic arial rthythm have improved after treatment with digoxin or after combined therapy with amidarone and digoxin. Junctional ectopic tachycardia is partially controlled with mexiletine. 3) The shortening fractions of left ventricle at diagnosis were 14-21% and improved to over 30% in all after 2 to 9 months of follow-up. CONCLUSIONS: We have shown that control of persistent tachycardia resolved the left ventricular dysfunction. We suggest that patients with dilated cardiomyopathy be carefully screened for tachyarrhythmia as a curable cause of ventricular dysfunction and that left ventricular function be assessed in the asymptomatic patients with persistent tachycardia.

Fibrilação; ventricular em pacientes com forma permanente da taquicardia juncional reciprocante / Ventricular fibrillation in a patient with the permanent form of junctional reciprocating tachycardia

Homem de 20 anos, portador de taquicardia de apresentaçäo incessante há longos anos, sem resposta a medicaçöes antiarrítmicas. Seis meses antecedendo a admissäo referia paroxismos de taquicardia mais rápida, de duraçäo curta, autolimitada. Na admissäo apresentava flutter atrial com conduçäo 1:1 (250 bpm) que degenerou em fibrilaçäo ventricular, revertida com 350J. O estudo eletrofisiológico identificou taquicardia atrioventricular, utilizando conexäo anômala "oculta" de localizaçäo póstero-septal deita com conduçäo lenta e propriedade decremental, conduçäo atrioventricular acelerada, observando-se precipitaçäo de fibrilaçäo atrial com resposta rápida pós-atropinizaçäo. Foi submetido a ablaçäo por cateter pro radiofrequência com sucesso. Esta assintomático, 18 meses após o procedimento.

Taquicardia incesante de la unión: características clínicas, electrofisiológicas y rol de la fulguración en 5 casos / Permanent form of junctional tachycardia: clinical and electrophysiological characteristics and fulguration role in 5 cases

The permanent form is a variety of functional reciprocating tachycardia that is refractory to medical treatment. The anterograde arm of the circuit is formed by the His Purkinje bundle and the retrograde conduction is through a slow conduction accesory atrioventricular pathway. We report five patients with this type of arrhythmia, subjected to electrophysiological assessment. Their mean age was 37 years, all suffered from palpitations and several medical treatments had failed. During tachycardia, electrocardiogram had a negative P wave in inferior leads and RP interval was bigger than PR interval. Accesory Pathway were located in the right postero-septal region in three patients, in the left postero-septal region in one and in the left lateral in one. Specific bundle fulguration was succesfully attempted in four patients, in whom arrythmias did not recur without medical treatment