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.

Dexmedetomidine and magnesium sulfate in preventing junctional ectopic tachycardia after pediatric cardiac surgery.

BACKGROUND: Junctional ectopic tachycardia (JET) is a serious tachyarrhythmia following pediatric cardiac surgery. It isn't easy to treat and better to be prevented. This study aimed to examine the prophylactic effects of dexmedetomidine, MgSO4, or their combination in reducing JET following pediatric open cardiac surgery. METHODS: Hundred and twenty children under 5 years, weighing more than 5 kg, who were scheduled for corrective acyanotic cardiac surgeries were randomized into three groups. Group MD (Dexmedetomidine-MgSO4 group): received dexmedetomidine 0.5 µg/kg IV over 20 min after induction, then infusion 0.5 µg/kg/h for 72 h, and 50 mg/kg bolus of MgSO4 with aortic cross-clamp release, then continued administration for 72 h postoperatively at a dose of 30 mg/kg/day. Group D (the dexmedetomidine group) received the same dexmedetomidine as the MD group in addition to normal saline instead of MgSO4. Group C (control group): received normal saline instead of dexmedetomidine and MgSO4. The primary outcome was the detection of JET incidence; the secondary outcomes were hemodynamic parameters, ionized Mg, vasoactive-inotropic score, extubation time, PCCU and hospital stay, and perioperative complications. RESULTS: The incidence of JET was significantly reduced in Group MD and Group D (p = .007) compared to Group C. Ionized Mg was significantly higher in Group MD than in Groups D and C during rewarming and in the ICU (p < .001). Better hemodynamic profile in Group MD compared to Group D and Group C throughout surgery and in the ICU, the predictive indexes were significantly better in Group MD than in Groups D and C (p < .001). Including the extubation time, PCCU, and hospital stay. CONCLUSION: Dexmedetomidine alone or combined with MgSO4 had a therapeutic role in the prevention of JET in children after congenital heart surgery.

Ivabradine for congenital ectopic tachycardia in newborn.

INTRODUCTION: 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. CASE: 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. CONCLUSION: 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.

Ivabradine in a 15-day-old male neonate with refractory focal atrial tachycardia.

Ivabradine is used to reduce heart rate in children with chronic heart failure and dilated cardiomyopathy, it has recently been used off-label to treat tachyarrhythmias such as ectopic atrial tachycardia and junctional ectopic tachycardia (JET) in children. We report a successful ivabradine experience in a male neonate with refractory focal atrial tachycardia (FAT).

Lyme carditis presenting as paroxysmal junctional tachycardia and complete atrioventricular block in an adolescent.

We describe a case of a previously healthy adolescent who presented with junctional tachycardia and complete atrioventricular (AV) block due to Lyme carditis. The simultaneous presence of these findings suggested significant inflammation of the AV junction. Junctional tachycardia, particularly if seen in a patient with conduction abnormalities and potential tick exposure, should increase suspicion for Lyme carditis.

Hemodynamic profile effects of PM101 amiodarone formulation in patients with post-operative tachyarrhythmias.

Amiodarone may be considered for patients with junctional ectopic tachycardia refractory to treatment with sedation, analgesia, cooling, and electrolyte replacements. There are currently no published pediatric data regarding the hemodynamic effects of the newer amiodarone formulation, PM101, devoid of hypotensive agents used in the original amiodarone formulation. We performed a single-center, retrospective, descriptive study from January 2012 to December 2020 in a pediatric ICU. Thirty-three patients were included (22 male and 11 female) between the ages of 1.1 and 1,460 days who developed post-operative junctional ectopic tachycardia or other tachyarrhythmias requiring PM101. Data analysis was performed on hemodynamic parameters (mean arterial pressures and heart rate) and total PM101 (mg/kg) from hour 0 of amiodarone administration to hour 72. Adverse outcomes were defined as Vasoactive-Inotropic Score >20, patients requiring ECMO or CPR, or patient death. There was no statistically significant decrease in mean arterial pressures within the 6 hours of PM101 administration (p > 0.05), but there was a statistically significant therapeutic decrease in heart rate for resolution of tachyarrhythmia (p < 0.05). Patients received up to 25 mg/kg in an 8-hour time for rate control. Average rate control was achieved within 11.91 hours and average rhythm control within 62 hours. There were four adverse events around the time of PM101 administration, with three determined to not be associated with the medication. PM101 is safe and effective in the pediatric cardiac surgical population. Our study demonstrated that PM101 can be used in a more aggressive dosing regimen than previously reported in pediatric literature with the prior formulation.

Comparison of the effects of conventional method and primary sutureless techniques on early postoperative rhythm problems in patients with total abnormal pulmonary venous return anomaly.

BACKGROUND: Total abnormal pulmonary venous return anomaly is a CHD characterised by abnormal pulmonary venous flow directed to the right atrium. In this study, we aimed to compare the effects of these techniques on early rhythm problems in total abnormal pulmonary venous return anomaly cases operated with conventional or primary sutureless techniques. METHOD: Seventy consecutive cases (median age 1 month, median weight 4 kg) who underwent total abnormal pulmonary venous return anomaly repair with conventional or primary sutureless technique between May 1 2020 and May 1 2022 were evaluated. The rate, diagnosis, and possible risk factors of postoperative arrhythmias were investigated. The results were evaluated statistically. RESULTS: When the total abnormal pulmonary venous return anomaly subgroup of 70 cases was evaluated, 40 cases were supracardiac, 18 cases were infracardiac, 7 cases were cardiac, and 5 cases were mixed type. Twenty-eight (40%) cases had a pulmonary venous obstruction. Primary sutureless technique (57%, supracardiac n = 24, mixed = 3, infracardiac = 13) was used in 40 patients. Median cardiopulmonary bypass time (110 versus 95 minutes) and median aortic clamp time (70 versus 60 minutes), median peak lactate (4.7 versus 4.8 mmol/l) in the first 72 hours, and median peak vasoactive inotropic score in the first 72 hours of the primary sutureless and conventional technique used cases value (8 versus 10) were similar. The total incidence of arrhythmias in the conventional group was significantly higher than in the primary sutureless group (46.7% versus 22.5%, p = 0.04). Supraventricular early beat was observed in 3 (7.5%), sinus tachycardia was seen in 6 (15%), junctional ectopic tachycardia was seen in 1 (2.5%), intra-atrial reentry tachycardia was seen in 1 (2.5%), usual supraventricular tachyarrhythmia was seen in 2 cases (5%) in the primary sutureless group. In the conventional group, supraventricular early beat was observed in six of the cases (20%), sinus tachycardia in five (16.7%), junctional ectopic tachycardia in four (13.3%), intra-atrial reentry tachycardia (10%) in three, and supraventricular tachyarrhythmia in seven cases (23.3%). In the first 30 days, there was a similar mortality rate (10% versus 10%), with four patients in the primary sutureless group and three in the conventional group. The median follow-up period of the cases was 8 months (interquartile range (IQR) 6-10 months). In the follow-up, arrhythmias were detected in two cases (one supraventricular tachyarrhythmia and one intra-atrial reentry tachycardia) in the primary sutureless group and three cases (two supraventricular tachyarrhythmia, one intra-atrial reentry tachycardia) in the conventional technique. All cases were converted to normal sinus rhythm with cardioversion and combined antiarrhythmic therapy. CONCLUSION: Different arrhythmias can be observed in the early period in patients with operated total abnormal pulmonary venous return anomaly. Although a higher rate of rhythm problems was observed in the early period in the conventional method compared to the primary sutureless technique, no significant effect was found on mortality and morbidity between the groups.

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.

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.

Routine Perioperative Esmolol After Infant Tetralogy of Fallot Repair: Single-Center Retrospective Study of Hemodynamics.

OBJECTIVES: Currently, surgical repair of tetralogy of Fallot (TOF) is associated with an 1.1% 30-day mortality rate. Those with junctional ectopic tachycardia (JET) and restrictive right ventricular physiology have poorer outcomes. Routine postoperative adrenergic or inodilator therapy has been reported, while beta-blockade following cardiopulmonary bypass has not. This study evaluated routine perioperative treatment with esmolol in infants undergoing TOF repair. DESIGN: Retrospective chart review of the perioperative course following TOF repair. SETTING: Single-center case series describing perioperative management of TOF in a cardiac ICU. PATIENTS: This study reviewed all patients less than 18 months old who underwent TOF repair, excluding cases of TOF with absent pulmonary valve or atrioventricular septal defect, at our institution from June 2018 to April 2021. INTERVENTIONS: This review investigates the hemodynamic effects of esmolol following cardiopulmonary bypass for TOF repair. MEASUREMENTS AND MAIN RESULTS: Preoperative clinical characteristics and perioperative course were extracted from the medical record. Descriptive statistics were used. Twenty-six patients receiving perioperative esmolol after TOF repair were identified and included. Postoperative hemodynamic parameters were within a narrow range with minimal vasoactive support in most patients. Three of 26 patients experienced JET, and one of 26 of whom had a brief cardiac arrest. Median and interquartile range (IQR) for hospital and postoperative length of stay was 7 days (IQR, 6-9 d) and 6 days (IQR, 5-8 d), respectively. There were no 30-day or 1-year mortalities. CONCLUSIONS: In this infant cohort, our experience is that the routine use of postoperative esmolol is associated with good cardiac output with minimal requirement for vasoactive support in most patients. We believe optimal postoperative management of infant TOF repair requires a meticulous multidisciplinary approach, which in our experience is enhanced with routine postoperative esmolol treatment.

Coexistence of sinus bradycardia and junctional tachycardia in a patient with fibrotic atrial cardiomyopathy.

A 65-year-old woman was referred for catheter ablation in the treatment of persistent tachycardia after surgery for atrial fibrillation and mitral regurgitation. Bipolar voltage mapping of both atria revealed that severe and extensive atrial fibrosis isolated the sinoatrial node from the atrioventricular junction and led to the coexistence of sinus bradycardia and persistent junctional tachycardia.

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.

Ivabradine in Post-operative Junctional Ectopic Tachycardia (JET): Breaking New Ground.

Junctional ectopic tachycardia (JET) is the commonest tachyarrhythmia in the early post-operative period in children undergoing open-heart surgery. It frequently leads to hemodynamic instability and needs to be managed aggressively. Amiodarone is the first-line agent along with non-pharmacological interventions. We report our initial experience with the use of Ivabradine in post-operative JET. A retrospective case records review of children with post-operative JET during the period from June 2018 to May 2019 was performed. Eight patients with post-operative JET were treated with Ivabradine during this period. The first patient was initially treated with Amiodarone. All eight patients responded to Ivabradine. The initial response was rate control permitting overdrive pacing. One patient had recurrence of JET 10 h after Ivabradine and after return to sinus rhythm. Amiodarone was administered along with the second dose of Ivabradine resulting in remission to sinus rhythm. Ivabradine appears to be an effective alternative to Amiodarone in children with post-operative JET based on our initial clinical experience.

Cardiovascular Collapse with Intravenous Amiodarone in Children: A Multi-Center Retrospective Cohort Study.

OBJECTIVE: To determine the incidence of cardiovascular collapse in children receiving intravenous (IV) amiodarone and to identify the population at risk. DESIGN: A multicenter study of patients ≤ 18 years of age who received intravenous amiodarone between January 2005 and December 2015. A retrospective analysis was performed to identify patients who developed cardiovascular collapse (bradycardia and/or hypotension). RESULTS: Of 456 patients who received amiodarone, cardiovascular collapse occurred in 47 patients (10%). Patient risk factors for collapse in a univariate analysis were as follows: age < 3 months (p = 0.04), depressed cardiac function (p < 0.001), blood pressure below 3rd percentile (p < 0.001), high lactate at baseline (p < 0.001). Administration risk factors included bolus administration (p = 0.04), and bolus administration over ≤ 20 min (p = 0.04). In multivariate analysis, age, baseline blood pressure less than 3rd percentile, and rapid bolus delivery were independent risk factors for cardiovascular collapse in the study group. The mortality rate was significantly higher in the collapse group (28% versus 8%). CONCLUSION: We found an association between IV amiodarone administration and the risk of developing cardiovascular collapse in a significant subset of children. Extreme caution and careful hemodynamic monitoring is recommended when using IV amiodarone in this population, especially in young infants, hemodynamically compromised patients, and in patients receiving rapid amiodarone bolus administration.

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.

Junctional ectopic rhythm after AVNRT ablation: An underrecognized complication.

BACKGROUND: Ablation is an effective treatment for atrioventricular nodal reentrant tachycardia (AVNRT). The occurrence of junctional ectopic rhythm (JER), including junctional ectopic tachycardia, following AVNRT ablation has been described as an extremely rare phenomenon, but may be underestimated. We aimed to determine the incidence of JER following AVNRT ablation within our institution, as well as that reported in the literature via an extensive review. METHODS: We reviewed our adult ablation institutional experience for the occurrence of JER after AVNRT ablation from 2009 to 2016. Additionally, we conducted an extensive literature search using different databases looking for AVNRT ablation case series. The individually reported complications of these studies were reviewed, with a primary endpoint defined as the occurrence of JER shortly after AVNRT ablation. The study was approved by our institutional review board. RESULTS: Our institutional data revealed 6/126 patients (prevalence 4.8%) developed non-preexisting JER post-AVNRT ablation. Four patients were asymptomatic. Two patients had persistent symptoms lasting over a year, with one patient requiring repeat ablation. The literature review included 149 adult and pediatric studies. There were three cases of reported JER, out of a total of 37,541 patients (31,768 adults and 5,773 pediatric; prevalence 0.008%). The three JER patients were pediatric, and all required further therapeutic intervention. CONCLUSION: JER might be an underreported complication of AVNRT ablation. It seems most often to be transient and self-limited, occurring days to weeks after ablation, but may also be debilitating, requiring more aggressive management.

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.

Efficacy of prophylactic dexmedetomidine in preventing postoperative junctional ectopic tachycardia in pediatric cardiac surgery patients: A systematic review and meta-analysis.

BACKGROUND: Junctional ectopic tachycardia is a serious tachyarrhythmic complication following pediatric cardiac surgery. It is difficult to manage and is associated with significant morbidity and mortality. Conventional nonpharmacological and pharmacological measures have shown limited effects. Dexmedetomidine is an α2 agonist which has recently been shown in multiple studies to be effective. AIMS: The aim of this systematic review with meta-analysis was to evaluate the efficacy of prophylactic dexmedetomidine administration in the prevention of junctional ectopic tachycardia in pediatric patients following cardiac surgeries. METHODS: We searched MEDLINE, EMBASE, Cochrane, Web of Science, and relevant references published in English before December 20, 2017 and performed meta-analysis on the selected studies, with one group receiving prophylactic perioperative dexmedetomidine administration and another group receiving placebo. The primary outcome was the incidence of junctional ectopic tachycardia, secondary outcomes included bradycardia, hypotension, intensive care unit stay, total hospital stay, inotropic scores, and total mechanical ventilation time. Odds ratio or mean difference with 95% confidence intervals were calculated using a random effect model. RESULTS: Seven studies (5 prospective randomized studies and 2 retrospective case-controlled studies) with a total of 1616 patients were analyzed. The incidence of junctional ectopic tachycardia in the dexmedetomidine group was significantly reduced compared to placebo. Similarly, intensive care unit stay, inotropic scores, and total mechanical ventilation time were also significantly decreased in the dexmedetomidine group. No significant increases in adverse events were found. Mortality was low in both groups. CONCLUSION: Prophylactic dexmedetomidine is effective in reducing the incidence of postoperative junctional ectopic tachycardia without significant increases in adverse events in pediatric patients undergoing surgery for congenital heart diseases.

Standardized training for AVT pacing in paediatric patients with postoperative junctional ectopic tachycardia.

BACKGROUND: Junctional ectopic tachycardia is a serious complication of surgery for paediatric congenital heart disease. R-wave synchronized atrial (AVT) pacing, an innovative temporary pacing technique, restores atrioventricular synchrony in these patients. The method is highly effective but technically complex. A standardized training model exists for doctors but not for paediatric intensive care nurses. AIMS: This study seeks to evaluate whether a standardized programme involving simulation and vignettes increases knowledge of AVT pacing and accuracy of its documentation, as well as recognition and management of specific complications. STUDY DESIGN: This study was an experimental simulation test with before and after descriptive evaluation. METHODS: A custom-made simulation model was used in combination with standardized training. Before and after training, 10 paediatric nurse specialists were asked to document pacing, to identify complications and to intervene as necessary. Four clinical scenarios were presented: effective AVT pacing, ineffective AVT pacing, pacing with narrow interval between atrial pacing and ventricular sensing and pacemaker-induced tachycardia. Identification and management of complications were evaluated using a 3-point scale. RESULTS: Training improved the quality of documentation and complication management. At outset, documentation by 1 of 10 participants was completely correct, and after training, documentation by 8 of 10 participants was completely correct. Before training, 30% of interpretations of the four presented clinical scenarios were correct (12/40) versus 83% (33/40) after training. The decision to notify a doctor of a complication was correct in 83% (33/40) before versus 95% (38/40) after the training. CONCLUSION: Standardized simulation training improves quality and safety in AVT pacing, with more accurate documentation of the pacing mode and better recognition and management of specific complications during pacing. RELEVANCE TO CLINICAL PRACTICE: AVT pacing should be performed in conjunction with standardized simulation training in paediatric cardiac intensive care units.