Elsevier

Heart Rhythm

Volume 20, Issue 7, July 2023, Pages 1011-1017
Heart Rhythm

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

https://doi.org/10.1016/j.hrthm.2023.03.005Get rights and content

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.

Introduction

Postoperative junctional rhythm is a common arrhythmia, especially after certain surgeries for congenital heart disease (CHD).1,2 Depending on the ventricular rate, it may be defined as accelerated junctional rhythm (AJR) or junctional ectopic tachycardia (JET), which are narrow QRS tachycardias with ventricular rates 100–170 bpm or >170 bpm, respectively.3 Both typically occur within 72 hours after cardiac surgery, and risk factors have been proposed from small series. AJR/JET most often occurs after procedures involving manipulation near the conduction system (eg, ventricular septal defect [VSD] closure, atrioventricular canal [AVC] repair, tetralogy of Fallot [TOF] repair, truncus arteriosus repair, Rastelli procedure), but also after other surgeries such as arterial switch operation, stage 1 palliation).1,2 Other risk factors include younger age, lower weight, longer cardiopulmonary bypass (CPB) times, aortic cross-clamp times, higher body temperature, postoperative inotrope use, and hypomagnesemia.1,4 The exact etiology is unknown, but it is hypothesized that postoperative AJR/JET results from a direct mechanical trauma or an indirect stretch injury of the conduction system precipitating automaticity of the bundle of His. This hypothesis is supported by the high incidence of transient postoperative heart block in patients with AJR/JET.5

Postoperative JET has been associated with increased morbidity, including longer ventilatory support and intensive care unit (ICU) stay.6 JET can potentially be life-threatening secondary to loss of atrioventricular (AV) synchrony and compromised ventricular filling in a heart with simultaneous depression of myocardial function after surgery.7,8 Studies suggest that perioperative treatment with dexmedetomidine, magnesium, or amiodarone may improve outcomes, but patient selection remains a challenge.9, 10, 11 However, there are no guidelines on which patients should receive prophylactic therapy.

In this study, we aimed to describe the incidence of AJR/JET, along with their impact on outcomes in a large cohort of patients who underwent surgery for CHD. In addition, we aimed to develop a risk prediction score to identify patients at highest risk for postoperative AJR and JET.

Section snippets

Population

This study was approved under exemption from informed consent by the Institutional Review Board at Boston Children’s Hospital and adhered to the Helsinki guidelines. We completed a retrospective cohort study including children aged 0–18 years who underwent cardiac surgery (with or without CPB) at Boston Children’s Hospital between 2011 and 2018. Patients who underwent orthotopic heart transplant, ventricular assist device implantation, primary extracorporeal membrane oxygenation (ECMO) or

Patient characteristics

A total of 6364 surgeries for CHD occurred during the study period in 5122 patients (n = 2826; 55% male). Median age at time of surgery was 0.9 [0.2–4.4] years. Heterotaxy syndrome was present in 295 patients (5%). Surgical repair included VSD closure in 1086 patients (17%), AVC repair in 347 (5%), arterial switch operation in 267 (4%), stage 1 palliation in 209 (3%), TOF repair in 165 (3%), Rastelli procedure in 75 (1%), and truncus arteriosus repair in 30 (0.4%). Among 6364 patients, 2636

Discussion

In this contemporary series, postoperative AJR occurred in 3.4% of surgeries and JET in 0.9% surgeries. AJR and JET were associated with prolonged ICU and hospital length of stays, but not early mortality. Risk factors included age, heterotaxy syndrome, ischemic time, and surgical procedure, which were then included in a risk prediction score. The ability to identify patients at highest risk for postoperative AJR/JET may provide an opportunity for preemptive intervention to decrease its risk

Conclusion

In this contemporary cohort, the risk of postoperative AJR/JET was low but was associated with prolonged ICU and hospital stays. With aggressive management, there was no increase in mortality. AJR/JET was associated with younger age, heterotaxy syndrome, specific surgical procedures (VSD closure, AVC repair), and longer ischemic times. These risk factors were used to create a score to predict the risk of postoperative AJR/JET. This may allow for early identification of at-risk patients and the

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  • Cited by (0)

    Funding Sources: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

    Disclosures: The authors have no conflicts of interest to disclose.

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