Epidemiology of Postoperative Junctional Ectopic Tachycardia in Infants Undergoing Cardiac Surgery.

BACKGROUND: Junctional ectopic tachycardia (JET) complicates congenital heart surgery in 2% to 8.3% of cases. JET is associated with postoperative morbidity in single-center studies. We used the Pediatric Cardiac Critical Care Consortium data registry to provide a multicenter epidemiologic description of treated JET. METHODS: This is a retrospective study (February 2019-August 2022) of patients with treated JET. Inclusion criteria were (1) <12 months old at the index operation, and (2) treated for JET <72 hours after surgery. Diagnosis was defined by receiving treatment (pacing, cooling, and medications). A multilevel logistic regression analysis with hospital random effect identified JET risk factors. Impact of JET on outcomes was estimated by margins/attributable risk analysis using previous risk-adjustment models. RESULTS: Among 24,073 patients from 63 centers, 1436 (6.0%) were treated for JET with significant center variability (0% to 17.9%). Median time to onset was 3.4 hours, with 34% present on admission. Median duration was 2 days (interquartile range, 1-4 days). Tetralogy of Fallot, atrioventricular canal, and ventricular septal defect repair represented >50% of JET. Patient characteristics independently associated with JET included neonatal age, Asian race, cardiopulmonary bypass time, open sternum, and early postoperative inotropic agents. JET was associated with increased risk-adjusted durations of mechanical ventilation (incidence rate ratio, 1.6; 95% CI, 1.5-1.7) and intensive care unit length of stay (incidence rate ratio, 1.3; 95% CI, 1.2-1.3), but not mortality. CONCLUSIONS: JET is treated in 6% of patients with substantial center variability. JET contributes to increased use of postoperative resources. High center variability warrants further study to identify potential modifiable factors that could serve as targets for improvement efforts to ameliorate deleterious outcomes.

Clinical risk prediction score for postoperative accelerated junctional rhythm and junctional ectopic tachycardia in children with congenital heart disease.

BACKGROUND: Accelerated junctional rhythm (AJR) and junctional ectopic tachycardia (JET) are common postoperative arrhythmias associated with morbidity/mortality. Studies suggest that pre- or intraoperative treatment may improve outcomes, but patient selection remains a challenge. OBJECTIVES: The purpose of this study was to describe contemporary outcomes of postoperative AJR/JET and develop a risk prediction score to identify patients at highest risk. METHODS: This was a retrospective cohort study of children aged 0-18 years undergoing cardiac surgery (2011-2018). AJR was defined as usual complex tachycardia with ≥1:1 ventricular-atrial association and junctional rate >25th percentile of sinus rate for age but <170 bpm, whereas JET was defined as a rate >170 bpm. A risk prediction score was developed using random forest analysis and logistic regression. RESULTS: Among 6364 surgeries, AJR occurred in 215 (3.4%) and JET in 59 (0.9%). Age, heterotaxy syndrome, aortic cross-clamp time, ventricular septal defect closure, and atrioventricular canal repair were independent predictors of AJR/JET on multivariate analysis and included in the risk prediction score. The model accurately predicted the risk of AJR/JET with a C-index of 0.72 (95% confidence interval 0.70-0.75). Postoperative AJR and JET were associated with prolonged intensive care unit and hospital length of stay, but not with early mortality. CONCLUSION: We describe a novel risk prediction score to estimate the risk of postoperative AJR/JET permitting early identification of at-risk patients who may benefit from prophylactic treatment.

Perioperative junctional ectopic tachycardia associated with congenital heart disease: risk factors and appropriate interventions.

The risk factors and the appropriate interventions for perioperative junctional ectopic tachycardia (JET) in congenital heart disease (CHD) surgery have not been sufficiently investigated despite the severity of this complication. This study aimed to examine the risk factors and interventions for perioperative JET. From 2013 to 2020, 1062 surgeries for CHD (median patient age: 4.3 years, range 0.0-53.0) with or without a cardiopulmonary bypass (CPB) were performed at Hokkaido University, Japan. We investigated the correlation between perioperative JET morbidity factors, such as age, genetic background, CPB/aortic cross-clamp (ACC) time, use of inotropes and dexmedetomidine, STAT score, and laboratory indices. The efficacy of JET therapies was also evaluated. Of the 1062 patients, 86 (8.1%) developed JET. The 30-day mortality was significantly high in JET groups (7% vs. 0.8%). The independent risk factors for JET included heterotaxy syndrome [odds ratio (OR) 4.83; 95% confidence interval (CI) 2.18-10.07], ACC time exceeding 90 min (OR 1.90; CI 1.27-2.39), and the use of 3 or more inotropes (OR 4.11; CI 3.02-5.60). The combination of anti-arrhythmic drugs and a temporary pacemaker was the most effective therapy for intractable JET. Perioperative JET after CHD surgery remains a common cause of mortality. Inotrope use was a risk factor for developing JET overall surgery risk. In short ACC surgeries, heterotaxy syndrome could increase the risk of JET, which could develop even without inotrope use in long ACC surgeries. It is crucial not to delay the treatment in cases with unstable hemodynamics caused by this arrhythmia. It is recommended to reduce numbers not dose of inotropes.

Atypical fetal junctional ectopic tachycardia: a case report and literature review.

BACKGROUND: Junctional ectopic tachycardia (JET) is caused by ectopic rhythms, originating in the atrioventricular node, typically with heart rate between 200 and 250 bpm. Herein, we present a case of fetal JET with normal fetal heart rate and a review of nine cases. CASE PRESENTATION: A 32-year-old, gravida 2, para 1, woman in whom fetal JET could not be diagnosed prenatally because the fetal heart rate was within the normal range. The fetus was diagnosed with premature restriction of the foramen ovale, and a cesarean section was performed, owing to the right heart overload that was characterized by fetal ascites and abnormal fetal Doppler velocity. Postnatally, the female neonate was diagnosed with JET on a 12-lead electrocardiogram, which revealed a neonatal heart rate of 158 bpm with narrow QRS and atrioventricular dissociation. After failure to respond to amiodarone therapy, she was treated with flecainide, which controlled the JET rate from 120 to 150 bpm. Fetal tachycardia with ventriculo-atrial (VA) dissociation or 1:1 VA conduction with a shorter VA interval than that of atrioventricular reentrant tachycardia confirmed the diagnosis of fetal JET. CONCLUSIONS: JET should be suspected even in the absence of tachycardia in patients with ductus venosus and pulmonary vein retrograde flow or tricuspid and mitral regurgitation without a cardiac anomaly, as tachycardia might sometimes be intermittent in cases of JET.

ß1-receptor polymorphisms and junctional ectopic tachycardia in children after cardiac surgery.

Junctional ectopic tachycardia (JET) is a potentially life-threatening postoperative arrhythmia in children with specific congenital heart defects and can contribute significantly to postoperative morbidity for at-risk populations. In adults, ß1-adrenergic receptor (ADRB1) and ß2-adrenergic receptor (ADRB2) genotypes have been associated with increased risk for arrhythmias. However, their association with arrhythmia risk in children is unknown. We aimed to test associations between ADRB1 and ADRB2 genotypes and postoperative JET in patients with congenital heart defects. Children who underwent cardiac surgery were genotyped for the ADRB1 p.Ser49Gly (rs1801252; c.145A>G), p.Arg389Gly (rs1801253; c.1165C>G), ADRB2 p.Arg16Gly (rs1042713; c.46A>G), and p.Glu27Gln (rs1042714; c.79G>C) polymorphisms. The occurrence of postoperative JET was assessed via cardiologist-interpreted electrocardiograms. Genotype associations with JET were analyzed via logistic regression, adjusted for clinical variables associated with JET, with separate analysis in patients not on a ß-blocker. Of the 343 children included (median age 8 months, 53% boys, 69% European ancestry), 45 (13%) developed JET. The Arg389Arg genotype was not significantly associated with JET in the overall population (odds ratio [OR] = 1.96, 95% confidence interval [CI] = 0.96-4.03, p = 0.064), but was nominally associated in patients not taking a ß-blocker (n = 324, OR = 2.25, 95% CI = 1.05-4.80. p = 0.034). None of the other variants were associated with JET. These data suggest that the ADRB1 Arg389Arg genotype may predict risk for JET following cardiac surgery in pediatric patients in the absence of ß-blockade. Whether treatment with a ß-blocker ameliorates this association requires further research.

A Comparative Effectiveness Systematic Review and Meta-analysis of Drugs for the Prophylaxis of Junctional Ectopic Tachycardia.

BACKGROUND: Junctional Ectopic Tachycardia (JET) is an arrhythmia originating from the AV junction, which may occur following congenital heart surgery, especially when the intervention is near the atrioventricular junction. OBJECTIVE: The aim of this systematic review and meta-analysis is to compare the effectiveness of amiodarone, dexmedetomidine, and magnesium in preventing JET following congenital heart surgery. METHODS: This meta-analysis was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement, where 11 electronic databases were searched from the date of inception to August 2020. The incidence of JET was calculated with the relative risk of 95% Confidence Interval (CI). Quality assessment of the included studies was assessed using the Consolidated Standards of Reporting Trials (CONSORT) 2010 statement. RESULTS: Eleven studies met the predetermined inclusion criteria and were included in this meta-analysis. Amiodarone, dexmedetomidine, and magnesium significantly reduced the incidence of postoperative JET [Amiodarone: risk ratio 0.34; I2= 0%; Z=3.66 (P=0.0002); 95% CI 0.19-0.60. Dexmedetomidine: risk ratio 0.34; I2= 0%; Z=4.77 (P<0.00001); 95% CI 0.21-0.52. Magnesium: risk ratio 0.50; I2= 24%; Z=5.08 (P<0.00001); 95% CI 0.39-0.66]. CONCLUSION: All three drugs have shown promising results in reducing the incidence of JET. Our systematic review found that dexmedetomidine is better in reducing the length of ICU stays as well as mortality. In addition, dexmedetomidine also has the least pronounced side effects among the three. However, it should be noted that this conclusion was derived from studies with small sample sizes. Therefore, dexmedetomidine may be considered as the drug of choice for preventing JET.

Sotalol versus amiodarone for postoperative junctional tachycardia after congenital heart surgery.

BACKGROUND: Junctional ectopic tachycardia (JET) is a common arrhythmia after congenital heart disease surgery. There is variability in the choice of antiarrhythmic therapy, with amiodarone used commonly. Intravenous (IV) sotalol is a newly available agent that may be useful for JET. OBJECTIVE: The purpose of this study was to evaluate the safety and efficacy of IV sotalol for postoperative JET and compare outcomes with IV amiodarone. METHODS: This is a retrospective single-center study of all patients who received IV sotalol or IV amiodarone for postoperative JET at Texas Children's Hospital from December 15, 2015, to December 15, 2020. Data included antiarrhythmic efficacy, hemodynamics, and adverse effects. Successful JET control was defined as a decrease in JET rate to <170 beats/min (or decrease by >20%), or conversion to sinus rhythm, with persistent control over 24 hours without requiring alternative antiarrhythmics or mechanical support. RESULTS: A total of 32 patients (median age 71 days; interquartile range 17-221 days) received IV amiodarone (n = 20 [62%]) or IV sotalol (n = 12 [38%]) for postoperative JET. Amiodarone was successful in treating JET in 75% of cases; sotalol was successful in 83%. The JET rate decreased faster over the first 90 minutes after a sotalol bolus (25 beats/min per hour) than after an amiodarone bolus (8 beats/min per hour) (P < .01); no heart rate difference was seen after 24 hours. Amiodarone infusion was discontinued early because of hypotension/bradycardia in 2 patients; this was not required in any patients receiving sotalol. CONCLUSION: For children with postoperative JET, both IV sotalol and amiodarone are safe and efficacious. IV sotalol may lead to a faster improvement in heart rate.

The importance of sustained junctional tachycardia following cessation of radiofrequency current delivery in slow pathway ablation.

BACKGROUND: Apart from junctional rhythms during slow pathway ablation, there is limited knowledge about the junctional tachycardia persisting following ablation cessation. This study is conducted to determine the characteristics and significance of this rare arrhythmia. METHODS AND RESULTS: This study was done on 487 patients with AVNRT undergoing the radiofrequency ablation. The RF delivery-induced Supraventricular Tachycardia, persisting for a few minutes following the termination of ablation (post-ablation SVT) was investigated in this research. Atrial Overdrive Pacing (AOP) was applied to the post-ablation SVT to distinguish AVNRT from Junctional Tachycardia(JT). A total of 2337 RF-current deliveries were applied, and post-ablation SVT was observed in 81 of them. According to the electrophysiological studies, five of them (in five separate cases) were definitely diagnosed as JT. The overall incidence of post-ablation JT was about 1% of all patients. In these cases, RF energy was applied to the posteroseptal region and roof of the proximal coronary sinus. The mean Cycle Length (CL) of JTs was equal to 446 ±67ms. Following post- ablation JT termination, four cases met endpoints of successful ablation, demonstrating a positive predictive value of 80%. Atrioventricular (AV) block did not occur in any of the cases and reappearance of JT was not observed during procedure or mean follow-up period of 19.8 ± 8.4 months. CONCLUSIONS: Post-ablation JT is probably a transient Ischemia-induced arrhythmia that does not require further ablation. Thus, it is recommended to differentiate between the AVNRT and JT in post-ablation arrhythmias to avoid unnecessary RF application.

Junctional Tachycardia as a Diagnostic Criterion in Acute Rheumatic Fever.

Acute rheumatic fever (ARF) is an acute inflammatory process resulting in rheumatic carditis, one of the most common acquired heart diseases in youth. Among the clinical manifestations of carditis, pathologic valve regurgitation and atrioventricular block are included in the criteria for the diagnosis of ARF. Besides atrioventricular block, ARF may often present with other arrhythmias, such as junctional tachycardia (JT). However, JT is currently not recognized as a criterion for the diagnosis of ARF. Three adolescents presented in our hospital with JT, polyarthralgia, and laboratory signs of inflammation with evidence of preceding group A Streptococcus infection. None of the patients fulfilled the diagnostic criteria of ARF. On the basis of the presumed diagnosis of ARF, all 3 patients were treated with intravenous steroids. Steroid therapy was given, and JT converted to sinus rhythm within an average of 62 hours. Subsequent electrocardiograms revealed variable degree of atrioventricular block in all 3 patients, providing clinical evidence and fulfilling the diagnostic criteria of ARF. Patients were monitored for a total 2 to 8 days before discharge on standard antiinflammatory treatment. Follow-up electrocardiograms and Holter monitoring revealed resolution of the atrioventricular block and lack of JT recurrence in all patients. On the basis of these sentinel cases, we propose that JT should be included as a diagnostic criterion for the diagnosis of ARF.

Ivabradine as an Adjunct for Refractory Junctional Ectopic Tachycardia Following Pediatric Cardiac Surgery: A Preliminary Study.

OBJECTIVES: Junctional ectopic tachycardia (JET) is a relatively common narrow complex rhythm typically characterized by atrioventricular dissociation or retrograde atrial conduction in a 1:1 pattern. Junctional ectopic tachycardia can be a life-threatening disorder, causing severe hemodynamic compromise and increased morbidity and mortality. The treatment of refractory JET can be very difficult, even with multimodal therapeutic interventions. The purpose of this study was to assess the role of ivabradine in cases of JET refractory to amiodarone and esmolol. METHODS: A total of 480 congenital heart surgeries were carried out at our center in 2017. Twenty (4.16%) patients had postoperative JET. Among these, five infants, aged 7 to 12 months (median: 8 months), had refractory JET. These patients (three tetralogy of Fallot, one ventricular septal defect, one complete atrioventricular septal defect) were treated with oral ivabradine in the dose range of 0.1 to 0.2 mg/kg/12 h as an adjunct to amiodarone. RESULTS: All five patients achieved rate reduction and eventual conversion to sinus rhythm. Mean duration to achieve heart rate of <140 bpm after initiation of ivabradine therapy was 16.8 hours (±7.2 hours), while mean duration to achieve sinus rhythm was 31.6 hours (±13.6 hours). No patient had any recurrence of JET. No patient exhibited any hemodynamic derangement nor side effects attributable to oral ivabradine. CONCLUSION: Oral ivabradine has the potential to be used as an adjunct to amiodarone in the treatment of JET in infants after surgery for congenital heart disease.

Risk Factors and Outcome of Post Fallot Repair Junctional Ectopic Tachycardia (JET).

BACKGROUND: Junctional ectopic tachycardia (JET) is a common arrhythmia causing hemodynamic impairment following corrective cardiac surgery such as tetralogy of Fallot (TOF) repair. METHODS: We report our experience with postoperative JET following surgical repair of TOF. The retrospective study was done from 2003 to 2012 with a total of 105 patients who underwent TOF repair. These patients' clinical and electrocardiographic data (pre-, intra-, and postoperative) were monitored to identify risk factors for the occurrence of JET and to evaluate the outcome of the affected patients. RESULTS: Incidence-Fourteen patients developed JET, with only four patients going directly from sinus rhythm to JET. In all others, either a transient atrioventricular (AV) block or a junctional rhythm preceded JET, mostly intraoperatively, showing a significant relation ( P = .010). Age-Patients with JET were of younger age ( P = .025) and had longer cardiopulmonary bypass ( P = .044) and aortic cross-clamping times ( P = .038). Increased cost and care-The occurrence of JET was associated with a longer stay in the intensive care unit (ICU) and a prolonged need for inotropic support and mechanical ventilation. Time to rate control correlated with length of ICU and hospital stay. MORTALITY: All JET patients converted into sinus rhythm, one of them died shortly after cessation of JET and two patients subsequently developed a first-degree AV block. CONCLUSION: The occurrence of JET remains an important complication during the initial postoperative period by increasing mechanical ventilation time, the need for inotropic support, and prolonging the length of ICU and hospital stay. Risk factors are younger age, longer aortic cross-clamping/bypass times, and intraoperative arrhythmias.

Efficacy of dexmedetomidine in prevention of junctional ectopic tachycardia and acute kidney injury after pediatric cardiac surgery: A meta-analysis.

OBJECTIVE: We conducted a meta-analysis to evaluate the effects of prophylactic perioperative dexmedetomidine administration on postoperative junctional ectopic tachycardia (JET) and acute kidney injury (AKI) in pediatric patients having undergone cardiac surgery. DESIGN: This systematic review was registered with PROSPERO (CRD42017083880). Databases including PubMed, Cochrane Central Register of Controlled Trials, and Web of Science were searched for randomized controlled trials (RCTs) and observational cohort studies from its inception to March 2018. Two reviewers independently screened literature, extracted data, and assessed the quality of included studies using the Jadad scale and Newcastle-Ottawa score. Meta-analysis was then conducted by RevMan 5.3 and Stata 12.0 software. P value < .05 was considered significant. RESULTS: A total of nine eligible studies (5 RCTs and 4 observational studies) comprising 1851 patients were selected for the final analysis. The results of meta-analysis showed that dexmedetomidine significantly reduced the incidence of postoperative JET (OR =0.35, 95% CI: 0.22 to 0.53, P < .00001), but there was no significant difference between groups in AKI (OR =0.44, 95% CI: 0.19 to 1.04, P = .06) and all-cause mortality (OR =0.87, 95% CI: 0.35 to 2.14, P = .77). CONCLUSIONS: The administration of perioperative dexmedetomidine effectively prevents JET in pediatric patients undergoing cardiac surgery but has no significant effect on postoperative renal function. However, the quality of evidence for these findings is low; thus, future larger scale randomized studies are needed to verify the real clinical effects of dexmedetomidine prophylaxis in pediatric patients.

Junctional ectopic tachycardia following tetralogy of fallot repair in children under 2 years.

BACKGROUND: Junctional ectopic tachycardia is a serious arrhythmia that frequently occurs after tetralogy of Fallot repair. Arrhythmia prophylaxis is not feasible for all pediatric cardiac surgery patients and identification of high risk patients is required. The objectives of this study were to characterize patients with JET, identify its predictors and subsequent complications and the effect of various treatment strategies on the outcomes in selected TOF patients undergoing total repair before 2 years of age. METHODS: From 2003 to 2017, 609 patients had Tetralogy of Fallot repair, 322 were included in our study. We excluded patients above 2 years and patients with preoperative arrhythmia. 29.8% of the patients (n = 96) had postoperative JET. RESULTS: JET patients were younger and had higher preoperative heart rate. Independent predictors of JET were younger age, higher preoperative heart rate, cyanotic spells, non-use of B-blockers and low Mg and Ca (p = 0.011, 0.018, 0.024, 0.001, 0.004 and 0.001; respectively). JET didn't affect the duration of mechanical ventilation nor hospital stay (p = 0.12 and 0.2 respectively) but prolonged the ICU stay (p = 0.011). JET resolved in 39.5% (n = 38) of patients responding to conventional measures. Amiodarone was used in 31.25% (n = 30) of patients and its use was associated with longer ICU stay (p = 0.017). Ventricular pacing was required in 4 patients (5.2%). Median duration of JET was 30.5 h and 5 patients had recurrent JET episode. Timing of JET onset didn't affect ICU (p = 0.43) or hospital stay (p = 0.14) however, long duration of JET increased ICU and hospital stay (p = 0.02 and 0.009; respectively). CONCLUSION: JET increases ICU stay after TOF repair. Preoperative B-blockers significantly reduced JET. Patients with preoperative risk factors could benefit from preoperative arrhythmia prophylaxis and aggressive management of postoperative electrolyte disturbance is essential.

Landiolol Hydrochloride Rapidly Controls Junctional Ectopic Tachycardia After Pediatric Heart Surgery.

OBJECTIVES: Junctional ectopic tachycardia is a supraventricular tachyarrhythmia with atrioventricular dissociation that causes life-threatening postsurgical conditions in pediatric heart patients. This study evaluates the efficacy of landiolol hydrochloride for managing junctional ectopic tachycardia. DESIGN: A single-center retrospective study. SETTING: PICU at the university hospital. PATIENTS: Of 561 pediatric patients who underwent open-heart surgery between 2006 and 2017, 10 patients developed sustained junctional ectopic tachycardia and were selected for landiolol treatment. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Landiolol decreased mean heart rate significantly from 206.1 ± 14.5 to 158.0 ± 8.6 beats/min within 2 hours after administration (p < 0.01). Mean time to achieve 20% heart rate reduction was 2.1 ± 0.5 hours. Systolic blood pressure between pre and post landiolol administration did not change significantly (72.6 ± 5.9 to 79.7 ± 6.2 mm Hg). Once junctional heart rate was sufficiently suppressed, atrioventricular sequential pacing was introduced to stabilize hemodynamics. Nine of 10 cases (90%) had atrioventricular sequential pacing to maintain appropriate heart rate and restore atrioventricular synchronicity under suppressed junctional heart rate. Subsequently, eight of 10 cases (80%) were converted to regular sinus rhythm within 24 hours after starting landiolol administration. The average time to achieve sinus rhythm conversion was 7.9 ± 3.4 hours. CONCLUSIONS: Landiolol rapidly suppresses junctional heart rate in junctional ectopic tachycardia after pediatric heart surgery without significant blood pressure compromises. Subsequent atrioventricular sequential pacing was effective at restoring atrioventricular synchronicity and stabilizing hemodynamics. Combining junctional rate control with landiolol and atrioventricular sequential pacing is therefore suggested as a promising option for prompt management of postoperative junctional ectopic tachycardia.

Arrhythmias in Children in Early Postoperative Period After Cardiac Surgery.

BACKGROUND: Postoperative arrhythmias are a known complication after cardiac surgical repairs for congenital heart disease. METHODS: Data were reviewed pertaining to incidence, diagnosis, potential risk factors, and management of postoperative arrhythmias in 369 consecutive patients under 18 years of age, undergoing elective open heart surgery. All children were admitted to the intensive care unit and continuous electrocardiographic monitoring was performed. Patient factors such as Aristotle Basic Complexity Score, total surgical duration, hypotension, tachycardia, serum lactate level, and inotropic score were analyzed. Univariate analysis was done to assess associations between these factors and the occurrence of postoperative arrhythmias. RESULTS: Twenty-five (6.7%) patients developed arrhythmias. Junctional ectopic tachycardia (JET) was the most common arrhythmia occurring in 15 (60%) patients, followed by supraventricular tachycardia in 3 (12%), ventricular premature contractions in 3 (12%), hemodynamically unstable ventricular tachycardia and fibrillation in 3 (12%), and atrial fibrillation in 1 (4%) patient. Different grades of heart block were noted in 13 patients. Aristotle score (P = .014), total surgical duration (P < .01), hypotension (P = .02), heart rate (beats per minute) (P = .001), serum lactate level (P = .04), and inotropic score (P = .02) in the early postoperative period were associated with arrhythmia occurrence. Surgeries for ventricular septal defect alone or in association with other diseases including tetralogy of Fallot (TOF) and transposition of the great arteries (TGA) were found to be associated with higher risk of arrhythmias. CONCLUSION: This study showed a low incidence of arrhythmias, JET being the commonest, seen more in TOF repair and these could be treated efficiently. Higher Aristotle score, longer surgical time, hypotension, tachycardia, high inotropic score, and high serum lactate levels were associated with the occurrence of arrhythmias postoperatively.

The Impact of Time to Rate Control of Junctional Ectopic Tachycardia After Congenital Heart Surgery.

BACKGROUND: Junctional ectopic tachycardia (JET) after congenital heart disease (CHD) surgery is often self-limiting but is associated with increased risk of morbidity and mortality. Contributing factors and impact of time to achieve rate control of JET are poorly described. METHODS: From January 2010 to June 2015, a retrospective, single-center cohort study was performed of children who developed JET after CHD surgery . We classified the cohort into two groups: patients who achieved rate control of JET in ≤24 hours and in >24 hours. We examined factors associated with time to rate control and compared clinical outcomes (mortality, duration of mechanical ventilation, length of intensive care unit [ICU], and hospital stay) between the two groups. RESULTS: Our cohort included 27 children, with a median age of 3 (interquartile range: 0.7-38] months. The most common CHD lesions were ventricular septal defect (n = 10, 37%), tetralogy of Fallot (n = 7, 25.9%), and transposition of the great arteries (n = 4, 14.8%). In all, 15 (55.6%) and 12 (44.4%) patients achieved rate control of JET in ≤24 hours and >24 hours, respectively. There was a difference in median mechanical ventilation time (97 [21-145) vs 311 [100-676] hours; P = .013) and ICU stay (5.0 [2.0-8.0] vs 15.5 [5.5-32.8] days, P = .023) between the patients who achieved faster rate control than those who didn't. There was no difference in length of hospital stay and mortality between the groups. CONCLUSION: Our study demonstrated that time to achieve rate control of JET was associated with increased duration of mechanical ventilation and ICU stay.

Ivabradine for junctional ectopic tachycardia in post congenital heart surgery.

We report two cases of malignant junctional ectopic tachycardia (JET), in infants following congenital heart surgery. After the failure of conventional therapy the arrhythmia was controlled by oral Ivabradine, a drug which is routinely used to lower heart rate in angina and heart failure in adult practice.

Selective autonomic stimulation of the AV node fat pad to control rapid post-operative atrial arrhythmias.

Junctional ectopic tachycardia (JET) and atrial fibrillation (AF) occur in patients recovering from open-heart surgery (OHS). Pharmacologic treatment is used for the control of post-operative atrial arrhythmias (POAA), but is associated with side effects. There is a need for a reversible, modulated solution to rate control. We propose a non-pharmacologic technique that can modulate AV nodal conduction in a selective fashion. Ten mongrel dogs underwent OHS. Stimulation of the anterior right (AR) and inferior right (IR) fat pad (FP) was done using a 7-pole electrode. The IR was more effective in slowing the ventricular rate (VR) to AF (52 +/- 20 vs. 15 +/- 10%, p = 0.003) and JET (12 +/- 7 vs. 0 +/- 0%, p = 0.02). Selective site stimulation within a FP region could augment the effect of stimulation during AF (57 +/- 20% (maximum effect) vs. 0 +/- 0% (minimum effect), p<0.001). FP stimulation at increasing stimulation voltage (SV) demonstrated a voltage-dependent effect (8 +/- 14% (low V) vs. 63 +/- 17 (high V) %, p<0.001). In summary, AV node fat pad stimulation had a selective effect on the AV node by decreasing AV nodal conduction, with little effect on atrial activity.

Virus myocarditis in a 1-month-old boy presenting as two types of paroxysmal supraventricular tachycardia.

Herein we describe the case of a 1-month-old boy with acute viral myocarditis, who presented with two kinds of paroxysmal supraventricular tachycardia, and who was cured after medical treatment. He was brought to the emergency room with poor feeding due to fever. On the third day of hospitalization, a narrow QRS tachycardia (180-200 beats/min) was detected. Echocardiography showed a high echoic area at the atrial septum around the atrioventricular node. The patient was clinically diagnosed with acute myocarditis. The narrow QRS tachycardia was diagnosed as incessant junctional ectopic tachycardia. The patient was treated with propranolol and landiolol. The frequency of the tachycardia decreased, but a different narrow QRS tachycardia was detected on the 15th day of hospitalization on electrocardiogram (220 beats/min), which was ascribed to atrioventricular nodal re-entrant tachycardia. Atenolol was effective for the tachycardia. At 2 years follow up, cardiac function was normal and tachycardia had not recurred.

Efficacy of Prophylactic Dexmedetomidine in Preventing Postoperative Junctional Ectopic Tachycardia After Pediatric Cardiac Surgery.

BACKGROUND: Postoperative junctional ectopic tachycardia is one of the most serious arrhythmias that occur after pediatric cardiac surgery, difficult to treat and better to be prevented. Our aim was to assess the efficacy of prophylactic dexmedetomidine in preventing junctional ectopic tachycardia after pediatric cardiac surgery. METHODS AND RESULTS: A prospective controlled study was carried out on 90 children who underwent elective cardiac surgery for congenital heart diseases. Patients were randomized into 2 groups. Group I (dexmedetomidine group): 60 patients received dexmedetomidine; Group II (Placebo group): 30 patients received the same amount of normal saline intravenously. The primary outcome was the incidence of postoperative junctional ectopic tachycardia. Secondary outcomes included bradycardia, hypotension, vasoactive inotropic score, ventilation time, pediatric cardiac care unit stay, length of hospital stay, and perioperative mortality. The incidence of junctional ectopic tachycardia was significantly reduced in the dexmedetomidine group (3.3%) compared with the placebo group (16.7%) with P<0.005. Heart rate while coming off cardiopulmonary bypass was significantly lower in the dexmedetomidine group (130.6±9) than the placebo group (144±7.1) with P<0.001. Mean ventilation time, and mean duration of intensive care unit and hospital stay (days) were significantly shorter in the dexmedetomidine group than the placebo group (P<0.001). However, there was no significant difference between the 2 groups as regards mortality, bradycardia, or hypotension (P>0.005). CONCLUSION: Prophylactic use of dexmedetomidine is associated with significantly decreased incidence of postoperative junctional ectopic tachycardia in children after congenital heart surgery without significant side effects.