A Case of Persistent Junctional Reciprocating Tachycardia Coincident With Cor Triatriatum Sinister.

Persistent junctional reciprocating tachycardia is a rare form of refractory atrioventricular reentrant tachycardia that accounts for <1% of supraventricular tachycardia in pediatrics. The accessory pathways are generally isolated with few reported underlying structural heart defects. We present a case of a five-month-old male with refractory tachyarrhythmia found to have cor triatriatum sinister, which to our knowledge, is the first reported case of these two rare anomalies coexisting.

A genetic contribution to risk for postoperative junctional ectopic tachycardia in children undergoing surgery for congenital heart disease.

BACKGROUND: Junctional ectopic tachycardia (JET) is a common arrhythmia complicating pediatric cardiac surgery, with many identifiable clinical risk factors but no genetic risk factors to date. OBJECTIVE: To test the hypothesis that the angiotensin-converting enzyme insertion/deletion (ACE I/D) polymorphism associates with postoperative JET. METHODS: DNA samples were collected from children undergoing the Norwood procedure; arterial switch operation; and repairs of Tetralogy of Fallot, balanced atrioventricular septal defect, and ventricular septal defect at a single center. The incidence of postoperative JET was associated with previously identified clinical risk factors and ACE I/D genotype. RESULTS: Of the 174 children who underwent the above-mentioned surgeries, 21% developed JET. Postoperative JET developed in 31% of children with the D/D genotype but only in 16% of those with the I/I genotype or the I/D genotype (P = .02). Clinical predictors of JET were selected a priori and included age, inotrope score, cardiopulmonary bypass time, and cross-clamp time. Multivariable logistic regression identified a significant correlation between the D/D genotype and postoperative JET independent of these predictors (odds ratio = 2.4; 95% confidence interval, 1.04-5.34; P = .04). A gene-dose effect was apparent in the homogeneous subset of subjects with atrioventricular septal defect (58% JET in D/D subjects, 12% JET in I/D subjects, and 0% JET in I/I subjects; P <.01). CONCLUSION: The common ACE deletion polymorphism is associated with a greater than 2-fold increase in the odds of developing JET in children undergoing surgical repair of atrioventricular septal defect, Tetralogy of Fallot, ventricular septal defect or the Norwood and arterial switch procedures. These findings may support the potential role of the renin-angiotensin-aldosterone system in the etiology of JET.

Cryoablation of junctional tachycardia at high risk of atrio-ventricular block.

INTRODUCTION: Transcatheter cryoablation is an alternative option for the treatment of supraventricular tachycardia, due to its very low risk of permanent atrio-ventricular block. However, the overcost of cryocatheter and the high recurrence rate of this emerging technology braked its large use. This study reports the results of an approach using cryoablation for the treatment of junctional tachycardia (JT) in selected patients at high risk of atrio-ventricular (AV) block. PATIENTS AND METHODS: Out of a series of 199 patients with JT treated by catheter ablation, 26 benefited from cryoablation (mean age 32.8+/-15 years, 15 males). The indications were the presence of an accessory pathway with a high risk of atrio-ventricular block (n=7), a slow pathway difficult to ablate, with a risk of atrio-ventricular block (n=7), a recurrence after a RF procedure, during which a transient atrio-ventricular block has occurred (n=4), and finally patients at young age (n=8). RESULTS: The primary success rate was 92%. No permanent AV block has been reported, neither with RF nor with cryoablation. The recurrence rate at 9+/-10 months was at 29% after cryoablation and 8.6% after RF. In case of AV nodal reentrant tachycardia, the additional cost of cryotherapy catheter has been avoided in 76.85% of cases. The use of a cryotherapy catheter and RF catheter has been necessary for the remaining cases. CONCLUSION: This study demonstrates that an approach, reserving cryoablation in selected patients at high risk of AV block is an alternative strategy to "the systematic use" of cryotherapy in the ablation of JT with a high efficacy, an excellent safety and a reduced cost.

Late occurrence of adenosine-sensitive focal junctional tachycardia in complex congenital heart disease.

BACKGROUND: Although supraventricular tachycardia in complex congenital heart disease (CHD) has been reported after surgical repair, its exact electrophysiologic identification has been limited to intraatrial reentrant tachycardia (IART). Moreover, junctional tachycardia (JT) has not previously been described as a cause of late postoperative arrhythmia. METHODS AND RESULTS: Since 1993, a total of 12 patients with congenital heart disease presented with paroxysmal focal JT. The patients with only typical immediate postoperative junctional ectopic tachycardia were excluded. Medical records, standard electrocardiography and Holter monitoring were reviewed. An intracardiac electrophysiologic (EP) study was performed in 11 patients. Ten patients were in post-Fontan status (5.7% of total Fontan survivors). Focal JT occurred more frequently in heterotaxy syndrome among the Fontan survivors (7/52 vs. 3/124; P < 0.05). The commonest anatomy of the atrioventricular (AV) junction was complete AV canal in 8 patients. EP characteristics of focal JT were as follows: (1) various tachycardia mechanisms were identified (increased automaticity or a triggered mechanism in 6/11, and focal reentry in 5/11, including one concealed nodofascicular pathway) (2) ventriculoatrial conduction during tachycardia was either dissociation (7/12) or variable (5/12) (3) All JTs were terminated by adenosine. Class III antiarrhythmic agent was effective in 5/6. His bundle ablation was performed in one Fontan patient, who already had pacemaker because of accompanying intractable IART and sinus node dysfunction. CONCLUSION: Focal JT may be a source of late term supraventricular tachycardia in patients with complex CHD. The tachycardia mechanism was either automatic/triggered or reentrant. In all patients, JT was effectively terminated by adenosine.

Impact of junctional ectopic tachycardia on postoperative morbidity following repair of congenital heart defects.

OBJECTIVE: To determine the incidence of postoperative junctional ectopic tachycardia (JET), we reviewed 343 consecutive patients undergoing surgery between 1997 and 1999. The impact of this arrhythmia on in-hospital morbidity and our protocol for treatment were assessed. METHODS: We reviewed the postoperative course of patients undergoing surgery for ventricular septal defect (VSD; n=161), tetralogy of Fallot (TOF; n=114), atrioventricular septal defect (AVSD; n=58) and common arterial trunk (n=10). All patients with JET received treatment, in a stepwise manner, beginning with surface cooling, continuous intravenous amiodarone, and/or atrial pacing if the haemodynamics proved unstable. A linear regression model assessed the effect of these treatments upon hours of mechanical ventilation, and stay on the cardiac intensive care unit (CICU). RESULTS: Overall mortality was 2.9% (n=10), with three of these patients having JET and TOF. JET occurred in 37 patients (10.8%), most frequently after TOF repair (21.9%), followed by AVSD (10.3%), VSD (3.7%), and with no occurrence after repair of common arterial trunk. Mean ventilation time increased from 83 to 187 h amongst patients without and with JET patients (P<0.0001). Accordingly, CICU stay increased from 107 to 210 h when JET occurred (P<0.0001). Surface cooling was associated with a prolongation of ventilation and CICU stay, by 74 and 81 h, respectively (P<0.02; P<0.02). Amiodarone prolonged ventilation and CICU stay, respectively, by 274 and 275 h (P<0.05; P<0.06). CONCLUSIONS: Postoperative JET adds considerably to morbidity after congenital cardiac surgery, and is particularly frequent after TOF repair. Aggressive treatment with cooling and/or amiodarone is mandatory, but correlates with increased mechanical ventilation time and CICU stay. Better understanding of the mechanism underlying JET is required to achieve prevention, faster arrhythmic conversion, and reduction of associated in-hospital morbidity.

[Long-term outcome of a hospital series of patients with atrio-ventricular accessory pathway]. / Devenir à long terme d'une série hospitalière de patients ayant une voie de conduction accessoire auriculo-ventriculaire.

Ninety five patients with a mean age of 39 +/- 19 years, 82 of whom were symptomatic, having an accessory atrioventricular bidirectional conduction pathway (WPW syndrome: 77; "concealed": 18) were followed up for an average of 7.3 +/- 2.6 years. The objectives were to analyse: the incidence and causes of death and the possible predictive factors of death due to the WPW syndrome--the influence of medical treatment and type of medication on survival and symptoms. Of the 8 cardiac deaths, 6 seemed to be related to the WPW syndrome, a prevalence of 7.8% and an annual incidence of 1.1/1000. The main risk factors which were identified were: age 62 +/- 8 years versus 37 +/- 15 years in survivors; p < 0.02--associated organic heart disease, especially ischaemic heart disease (5/6)--the description of severe symptoms, in particular recurrent syncope--documented malignant spontaneous or induced arrhythmias (5/6)--anterograde AV conduction with an effective refractory period < or = 230 msec in 4, though it was only 270 msec in the other 2 patients, indicating that this parameter is not specific--amiodarone (6/6) did not prevent the fatal outcome in this particular group of patients. In the "benign" forms, only betablocker drugs could significantly reduce the frequency and severity of symptoms, especially when compared with Class I or IC antiarrhythmics. These results suggest that the indications of radical treatment should be widened in high risk patients, especially when elderly and with associated coronary artery disease. They also suggest that the role of betablocker drugs should be reevaluated in the so-called "benign" symptomatic forms.

Ventricular paired pacing to control intractable junctional tachycardia following open heart surgery in a child.

A 5-month-old girl presented postoperatively with an atrioventricular (A-V) junctional tachycardia at a rate of 245/min following surgical repair of tetralogy of Fallot. The systolic blood pressure dropped to 60 mmHg with this rapid heart rate, and the infant became shocked. Drugs and overdrive pacing were ineffective in suppressing the A-V junctional tachycardia and in improving cardiac output. Ventricular paired pacing was used successfully to halve the mechanically effective ventricular rate and to restore cardiac output. When ventricular paired pacing was stopped after 12 h, the spontaneous rhythm was an atrial rhythm with 1-1 A-V conduction. The patient was discharged in sinus rhythm on the 5th postoperative day.