Neonatal supraventricular tachycardia

Ventricular Tachyarrhythmia in a Newborn Baby

Supraventricular tachycardia (SVT) is a narrow QRS complex tachyarrhythmia with a heart rate above 220 beats per minute in infants and children. Ventricular tachycardia can be due to electrolyte abnormalities, cardiomyopathies, congenital heart disease, myocarditis or drug toxicity. Incidence has been estimated to be 1 in 250 to 1 in 1000 with spontaneous resolution in infants by one year of life. We present a full-term neonate who started experiencing a tachyarrhythmia on day zero of life until she reverted to sinus rhythm on day nine of life. The rhythm was most likely a ventricular tachyarrhythmia rather than supraventricular tachycardia due to its unresponsiveness to adenosine, wide QRS complexes, and lack of association with hemodynamic instability. This is a unique case presentation of a ventricular tachyarrhythmia for its diagnostic and therapeutic challenges, it's idiopathic nature and lack of association with any cardiac compromise, congenital heart disease or electrolyte imbalance.

Antiarrhythmic therapy for narrow QRS supraventricular tachyarrhythmias in newborns and infants in the first year of life: Potent tools to be handled with care

Supraventricular tachyarrhythmias pose a significant challenge in neonates and infants, particularly within the first year of life, where prompt and effective management is crucial. By synthesizing available evidence and clinical experience, this review aims to provide a comprehensive overview of antiarrhythmic therapy in this vulnerable population, with a focus on narrow QRS supraventricular tachyarrhythmias. This review examines the current understanding of supraventricular tachyarrhythmia management and discusses the challenges associated with antiarrhythmic therapy in newborns and infants during the critical first year of life, evaluating the efficacy and safety of various antiarrhythmic agents commonly utilized in this population, including dosing considerations, adverse effects, and strategies for acute management and prophylactic long-term antiarrhythmic treatment.

Coarctation of the Aorta and Late-Onset Sepsis With Supraventricular Tachycardia: A Clinical Case Review

We report a case of an 11-day-old male infant who presented to our hospital with complaints of breathing difficulty and cough for two days prior to admission. The child had a seizure post-admission which was controlled with phenobarbitone. The child was connected to a mechanical ventilator. The baby also had persistent tachycardia, which upon doing an electrocardiogram (ECG) led to a diagnosis of supraventricular tachycardia (SVT). Additional investigations revealed the existence of late-onset sepsis (LOS), which was treated with appropriate antibiotics. In view of weak femoral pulses with normal brachial pulses, a diagnosis of coarctation of the aorta (CoA) was entertained. The diagnosis was confirmed by an echocardiogram, and the baby was transferred to a higher-level medical center for surgical correction. Regrettably, the baby succumbed to heart failure and shock on the 12th day of life. This case highlights the infrequency of CoA accompanied by SVT. The case delves into the challenges of diagnosing the condition, the necessary medical interventions, and the unforeseen complications that must be considered to reduce mortality in such circumstances.

Rediscover the predictive capacity of B-type natriuretic peptide applied to neonatal supraventricular tachycardia

BACKGROUND

Supraventricular tachycardia (SVT) is one of the most common non-benign arrhythmias in neonates, potentially leading to cardiac decompensation. This study investigated the early risk factors of acute heart failure (AHF) secondary to SVT in neonates, and explored their value in guiding the selection of effective anti-arrhythmic treatment.

METHODS

A total of 43 newborns diagnosed with and treated for SVT between January 2017 and December 2022 were analyzed. According to the presence of AHF after restoring sinus rhythm in newborns with SVT, they were divided into SVT with AHF group and SVT without AHF group. Clinical data and anti-arrhythmic therapies were analyzed. Risk factors of AHF secondary to SVT in neonates were determined using logistic regression. The cut-off value for predictors of AHF secondary to SVT and demanding of a second-line anti-arrhythmic treatment was determined through receiver operating characteristic (ROC) analysis.

RESULTS

Time to initial control of tachycardia > 24 h, hyperkalemia, anemia, and plasma B-type natriuretic peptide (BNP) were identified as risk factors of AHF secondary to SVT in neonates. BNP exhibited AUC of 0.80 in predicting AHF, and BNP > 2460.5pg/ml (OR 2.28, 95% CI 1.27 ~ 45.39, P = 0.03) was an independent predictor, yielding sensitivity of 70.6% and specificity of 84.6%. Neonates with BNP > 2460.5pg/ml (37.5% versus 7.4%, P = 0.04) had a higher demand for a second line anti-arrhythmic treatment to terminate SVT, with sensitivity and specificity for BNP in predicting at 75.0%, 71.4%, respectively.

CONCLUSIONS

BNP could be used to predict an incident of AHF secondary to SVT and a demand of second-line anti-arrhythmic treatment to promptly terminate SVT and prevent decompensation in neonates.

Triple Antiarrhythmic Therapy in Newborns with Refractory Atrioventricular Reentrant Tachycardia

Atrioventricular reentrant tachycardia (AVRT) is the most common form of supraventricular tachycardia in newborns. AVRT is sometimes refractory to conventional antiarrhythmic therapy. We describe our experience about the use of the triple combination of flecainide + propranolol + amiodarone as third-line regimen for refractory and recurrent AVRT in newborns. We considered a series of 14 patients who had failed both first-line and second-line therapy and were treated using the combination of flecainide + propranolol + amiodarone. Transoesophageal electrophysiologic study (TES) was performed to test the effectiveness of medical therapy during hospitalization and to try to reduce the amount of therapy, after amiodarone wash-out, before 1 year of age. TES was repeated at 1 year of age to test the spontaneous resolution of the arrhythmia after treatment discontinuation. Rhythm control was achieved in all 14 patients. At a mean age of 9.3 ± 2 months, AVRT was not inducible by TES in 11/12 amiodarone-free patients. At a mean age of 14.1 ± 3 months, AVRT was still inducible in 7/12 patients after interrupting the entire antiarrhythmic therapy (58.3%). Triple combination was effective as third-line option to suppress AVRT refractory to single and double antiarrhythmic therapy, with no significant adverse events. Our experience suggests that triple therapy could be maintained for a short-term treatment, discontinuing amiodarone before 1 year of age to avoid long-term side effects. Newborns who needed triple therapy appear to have a lower chance of accessory pathway disappearance at 1 year of age. TES could be useful for risk stratification of recurrences at the time of drug discontinuation in infants considered to be at higher risk of recurrent AVRT.

Assessing the Risk of Hypoglycemia Secondary to Propranolol Therapy for the Treatment of Supraventricular Tachycardia in Infants

Supraventricular tachycardia (SVT) is the most common arrhythmia among infants. Prevention of SVT is frequently managed through propranolol therapy. Hypoglycemia is a known adverse effect of propranolol therapy, but little research has been done on the incidence and risk of hypoglycemia in treatment of SVT in infants with propranolol. This study attempts to offer insight into the risk of hypoglycemia associated with propranolol therapy when treating infantile SVT to help inform future glucose screening guidelines. We conducted a retrospective chart review of infants treated with propranolol in our hospital system. Inclusion criteria were infants < 1 year of age who received propranolol for the treatment of SVT. A total of 63 patients were identified. Data was collected on sex, age, race, diagnosis, gestational age, nutrition source (Total Parenteral Nutrition (TPN) vs oral), weight (kg), weight for length (kg/cm), propranolol dose (mg/kg/day), comorbidities, and whether or not a hypoglycemic event was identified (< 60 mg/dL). Hypoglycemic events were identified in 9/63 (14.3%) patients. Of the patients with hypoglycemic events, 9/9 (88.9%) had comorbid conditions. Patients with hypoglycemic events had significantly lower weight and propranolol dose than those without hypoglycemic events. Weight for length also tended to increase risk for hypoglycemic events. The high incidence of comorbid conditions in the patients who had hypoglycemic events suggests that hypoglycemic monitoring may only be necessary in patients with conditions predisposing to hypoglycemia.

Low-dose aspirin use in the first trimester of pregnancy and odds of congenital anomalies: A meta-analysis of randomized controlled trials

BACKGROUND

Daily low-dose aspirin (LDA) is recommended in high-risk pregnancies. However, its safety profile in the first trimester has not been well documented.

OBJECTIVES

To determine if LDA exposure during the first trimester of pregnancy is associated with higher odds of congenital structural anomalies.

SEARCH STRATEGY

PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov were systematically searched.

SELECTION CRITERIA

Randomized controlled trials (RCTs) that assigned participants to LDA (≤150 mg) or placebo/no intervention at less than 14 weeks of pregnancy were eligible.

DATA COLLECTION AND ANALYSIS

Random-effects models were performed using the inverse-variance method to calculate pooled effect sizes. Quality of evidence was appraised according to Grading of Recommendations, Assessment, Development and Evaluations (GRADE) criteria.

MAIN RESULTS

Eight RCTs that included 7564 participants assigned to receive daily LDA and 7670 participants that served as controls were analyzed. Low-certainty evidence showed no significant difference in the odds of congenital anomalies (odds ratio 0.87, 95% confidence interval 0.62-1.23, I²  = 0%).

CONCLUSIONS

In this meta-analysis, there is no evidence to suggest safety concerns regarding LDA teratogenicity. However, given the overall low quality of evidence, further research (e.g. individual participant data meta-analysis) is needed to confirm LDA safety profile.

Ambulatory Cardiac Monitoring in Infants with Supraventricular Tachycardia

Supraventricular tachycardia (SVT) is a frequent cause of tachyarrhythmia in infants < 1 year of age and ambulatory cardiac monitoring is an important tool for diagnosis and follow-up of these patients. We retrospectively reviewed 594 infants (mean age 4.05 months, SD 3.55; 54% M) who underwent ambulatory cardiac monitoring (69% 24 h Holter, 31% extended monitor) through the Pocket ECG system (MediLynx) between January 2016 and July 2020. 170 patients who had the ICD-10 code I47.1 for SVT used at enrollment were analyzed separately. 49 (8.3%) patients had sustained SVT or non-sustained SVT (nSVT) during the study period, including 20 patients (11.8%) who had the ICD-10 code I47.1 at enrollment. Extended ambulatory cardiac monitors detected 61% of all patients with nSVT or SVT and was superior when compared to 24 h Holter (p < 0.0001). In the overall group, the first episode of SVT or nSVT was detected within 24 h of monitoring in 40/49 patients (82%). 48/49 patients (98%) were diagnosed within a week of monitoring and the single remaining patient was diagnosed with nSVT at day 15 of monitoring. There was no significant difference in minimal, maximal, and average heart rate between patients with and without ICD-10 code I47.1 at enrollment or between patients with and without SVT or nSVT. Despite their low yield, ambulatory cardiac monitors are an important diagnostic tool. The ideal length of monitoring in patients with known or suspected SVT has yet to be defined, although all patients in our cohort were identified by day 15 of monitoring.

Effective Control of Supraventricular Tachycardia in Neonates May Requires Combination Pharmacologic Therapy

INTRODUCTION

Supraventricular tachycardia (SVT) is one of the arrhythmias that can occur in newborns. Most SVT incidents in the neonatal period are spontaneously resolved around the first year of life, but since tachycardia can frequently occur before complete resolution, appropriate medication use is required. However, no clear guidelines or consensus on the treatment of neonatal SVT have been established yet.

METHODS

From January 2011 to December 2021, demographic data and antiarrhythmic medications used were retrospectively analyzed for 18 newborns diagnosed with SVT at a single center.

RESULTS

A total of four medications (propranolol, amiodarone, flecainide, and atenolol) were used as maintenance therapy to prevent tachycardia recurrence, and propranolol was the most used, followed by amiodarone. Thirty-nine percent of the patients were controlled with monotherapy, but the remainder required two or more medications. The median period from medication initiation after diagnosis to the last tachycardia event was 15.5 days, and the median total duration of medication use was 362 days. None of the patients experienced any side effects of antiarrhythmic medications. The total duration of medication use was statistically significant according to the mechanism of SVT, and the usage time of the increased automaticity group was shorter than that of the re-entry group.

CONCLUSION

Since most neonatal SVT resolves within 1 year, it is significant to provide prophylactic medication to prevent tachycardia recurrence at least until 1 year of age, and depending on the patient, the appropriate combination of medications should be identified.

Incidence of non-benign arrhythmia in neonatal intensive care unit: 18 years experience from a single center

Background

Non-benign arrhythmias, which require urgent recognition and care in neonatal intensive care unit (NICU) settings, are rare but can severely impact neonates. We aimed to clarify the epidemiology and characteristics of non-benign arrhythmias and their influence on neonates.

Methods

This single-center retrospective study included patients admitted to the NICU at Kurashiki Central Hospital between January 2001 and December 2019. Only patients with structurally normal hearts were included. The use of direct cardioversion (DC), antiarrhythmic agents, and the presence of risk factors was reviewed from medical records.

Results

Of the 8082 admissions, 2919 patients (36.1%) were low birth weight infants (LBWI) weighing less than 1500 g. There were 23 patients with arrhythmias (nine of them were LBWIs) with an incidence of 0.28%. There were 16 patients with tachyarrhythmia (eight supraventricular tachycardia [SVT] cases, three atrial flutters [AFL] cases, three ventricular tachycardia cases, two junctional ectopic tachycardia cases), and seven with bradyarrhythmia (all with complete atrioventricular [AV] block). For tachyarrhythmia cases, seven patients required DC, and eight were on antiarrhythmic agents at the time of discharge. Two patients (28.5%) with complete AV block required pacemaker implantation before discharge. The treatment strategy was dependent on the type of arrhythmia. All patients were discharged without significant morbidities.

Conclusions

The incidence of non-benign arrhythmias was as low as 0.28%. Arrhythmias can be managed successfully in neonates, yet risk factors related to mortality warrant further study.

When Adenosine Does Not Work: Apparent and Real Adenosine-Resistant Tachycardia

ABSTRACT

Supraventricular tachycardia (SVT) is the most common arrhythmia in the pediatric population. Adenosine is widely accepted as the first-line pharmacological treatment for hemodynamically stable SVT, constituting a class I recommendation in the 2020 American Heart Association guidelines for pediatric life support (2020 American Heart Association Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care). As most pediatric SVTs are dependent on the atrioventricular node (AVN) for their propagation, and adenosine acts primarily on the AVN, adenosine will frequently terminate the arrhythmia. The term "adenosine failure" is often used to describe when its administration does not result in sustained termination of the tachycardia. Because of its very short half-life, there is confusion between improper delivery, failure to have any effect on the tachycardia, or transient termination. There are some pediatric SVTs, which are not AVN dependent, and which truly are refractory to adenosine. Simultaneous electrocardiogram recording during administration can provide important information to differentiate between adenosine resistance and transient adenosine effect, thus guiding further management.

[Radiofrequency catheter ablation in pediatric population: clinical, electrophysiological and therapeutic characteristics in a Peruvian pediatric hospital]

Objective

This study aims to describe the clinical, electrophysiological and therapeutic characteristics of pediatric patients with supraventricular tachycardia undergoing radiofrequency ablation.

Materials and methods

Observational, descriptive, retrospective study of children admitted for supraventricular tachycardia treatment at the Instituto Nacional de Salud del Niño during 2018 to 2021.

Results

Data from 62 procedures were collected, corresponding to 59 patients (mean age: 9.91 years, 61% male), 23% of procedures were performed in patients under 15kg, and two were in patients under 5kg. 63% of patients had a structurally normal heart, while 37% had some type of congenital heart disease, the most common being Ebstein's anomaly. The most widely used group of drugs were beta-blockers, mainly propranolol. Among the arrhythmias treated, 21.7% had preexcitation Syndrome, 33.3% had at least one hidden accessory pathway, 5% corresponded to permanent reciprocating junctional tachycardia, 5% intranodal tachycardia, 11.7% atrial tachycardia, 10 % atrial flutter, 5% had other types of tachycardia and in 5 cases no tachycardia was induced. Of the total procedures, 76% corresponded to electrophysiological study and ablation, four patients recurred.

Conclusions

The most common supraventricular tachycardia substrate in children was the presence of some accessory pathway. Radiofrequency catheter ablation could be applied in children with a high success rate and a low complication rate.

Neonatal arrhythmias in Turner syndrome: a case report and review of the literature

Background

While left-sided congenital heart defects have been well described in females with Turner syndrome (45, X), the literature is scarce regarding arrhythmias in this patient population.

Case summary

A full-term neonate referred to cardiology was found to have a non-apex forming left ventricle and partial anomalous pulmonary venous return. During the echocardiogram, she developed atrial flutter, followed by orthodromic reentrant supraventricular tachycardia (SVT). She was started on propranolol and eventually switched to sotalol due to breakthrough SVT. A genetics evaluation revealed Turner syndrome with complete monosomy X (45, X). The patient is now 18 months old and has not had any further arrhythmias.

Discussion

We present a rare case of atrial flutter followed by supraventricular tachycardia in a neonate with Turner syndrome and left-sided heart defects. This case highlights the importance of early and precise investigation of cardiac abnormalities in neonatal patients, especially among females with Turner syndrome given their relatively higher risk of cardiovascular disease compared to the general population.

Treatment of Permanent Junctional Reciprocating Tachycardia in a Preterm Neonate: Case Report

Permanent junctional reciprocating tachycardia (PJRT) is most often observed in infants and children and can lead to incessant tachycardia. PJRT is usually refractory to medical treatment. Tachycardia may infrequently occur in the fetus in which case fetal tachycardia transplacental treatment should be started immediately. Term delivery is recommended for fetuses with tachycardia in the absence of significant clinical compromise to avoid complications of preterm birth. Herein, a 36-week preterm neonate presented with PJRT. He had tachycardia in the fetal period and was treated with digoxin, amiodaron, and esmolol therapy after birth without undergoing the catheter ablation procedure.