Sotalol in neonates for arrhythmias: Dosing, safety, and efficacy

INTRODUCTION

Various agents may be utilized to manage supraventricular tachycardia (SVT) in neonates and infants. Recently, sotalol has piqued interest given its reported success in managing neonates and infants with SVTs, especially with the intravenous formulation. While the manufacturer recommends using an age-related nomogram in neonates and young infants to guide doses, clinical reports describe various dosing based on weight (mg/kg) or on body surface area (BSA) in mg/m2 . Given the reported variation in clinical practice with regard to dosing in neonates, there is a gap in the literature and translation into clinical practice regarding applicability of the nomogram into clinical practice. The purpose of this study was to describe sotalol doses based on body weight and BSA in neonates for SVT.

METHODS

This is a single center retrospective study evaluating effective sotalol dosing from January 2011 and June 2021 (inclusive). Neonates who received intravenous (IV) or oral (PO) sotalol for SVT were eligible for inclusion. The primary outcome was to describe sotalol doses based on body weight and BSA. Secondary outcomes include comparison of doses to the manufacturer nomogram, description of dose titrations, reported adverse outcomes, and change in therapy. Two-sided Wilcoxon signed-rank tests were used to determine statistically significant differences.

RESULTS

Thirty-one eligible patients were included in this study. The median (range) age and weight were 16.5 (1-28) days and 3.2 (1.8-4.9) kg, respectively. The median initial dose was 7.3 (1.9-10.8) mg/kg or 114.3 (30.9-166.7) mg/m2 /day. Fourteen (45.2%) of patients required a dose increase for SVT control. The median dose required for rhythm control was 8.5 (2-14.8) mg/kg/day or 120.7 (30.9-225) mg/m2 /day. Of note, the median recommended dose per manufacturer nomogram for our patients would have been 51.3 (16.2-73.8) mg/m2 /day, which is significantly lower than both the initial dose (p < .001) and final doses (p < .001) utilized in our study. A total of 7 (22.9%) patients were uncontrolled on sotalol monotherapy using our dosing regimen. Two patients (6.5%) had reports of hypotension and one patient (3.3%) had a report of bradycardia requiring discontinuation of therapy. The average change in baseline QTC following sotalol initiation was 6.8%. Twenty-seven (87.1%), 3 (9.7%), 1 (3.3%) experienced prolongation, no change, or a decrease in QTc, respectively.

CONCLUSIONS

This study demonstrates that a sotalol strategy significantly higher than the manufacture dose recommendations are required for rhythm control in neonates with SVT. There were few adverse events reported with this dosing. Further prospective studies would be advantageous to confirm these findings.

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.

Multicenter cohort study on duration of antiarrhythmic medication for supraventricular tachycardia in infants

Antiarrhythmic medication (AM) is commonly used to prevent supraventricular tachycardia (SVT) recurrence in infants. Our aim was to determine whether a shorter duration of AM is sufficient to prevent atrioventricular reentrant tachycardia (AVRT) recurrence and evaluate risk factors for recurrence of SVT after discontinued AM.This multicenter cohort study included all infants diagnosed with SVT in the five university hospitals in Finland between 2005 and 2017. Those diagnosed between 2005 and 2012 received AM for 12 months (group 1), and those diagnosed between 2013 and 2017 received AM for 6 months (group 2). A total of 278 infants presented with AVRT (group 1, n = 181; group 2, n = 97), and the median AM duration was 12.0 months (interquartile range [IQR] 11.4-13.4) and 7.0 months (IQR 6.0-10.2), respectively. Propranolol was the most frequently used first-line AM (92% and 95%). Recurrence-free survival rates were over 88% until 12 months after AM prophylaxis in both groups, without any statistically significant difference between them. Independent risk factors for recurrence of SVT after discontinuation of AM were need of combination AM (HR 2.2, 95% CI 1.14-4.20), Wolff-Parkinson-White (WPW) syndrome (HR 2.4, 95% CI 1.25-4.59), and age over 1 month at admission (HR 2.2, 95% CI 1.12-4.48).    Conclusion: Shortening AM duration in infants from 12 to 6 months does not seem to lead to more frequent SVT recurrence. The risk factors for recurrence of SVT were WPW syndrome, need of combination AM, and age over 1 month.

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.

Report of a patient with refractory atrial tachycardia whose heart rate was controlled using ivabradine

Ivabradine is an effective treatment for focal atrial tachycardia. However, it may also be effective for re-entrant atrial arrhythmia. An 85-year-old woman with a history of underlying ischaemic cardiomyopathy complained of worsening symptoms of heart failure because of rapid atrial tachycardia that was resistant to several rate-controlling drugs, but responded well to ivabradine. An electrophysiology study demonstrated a roof-dependent macro-re-entrant tachycardia of the left atrium. Linear ablation of the left atrial roof resulted in termination of the tachycardia. Thus, ivabradine can be an effective treatment for re-entrant atrial tachycardia.

Fetal Supraventricular Tachycardia: What the Adult Cardiologist Needs to Know

Fetal supraventricular tachycardia management is challenging, with consequences for both the fetus and the mother. If left untreated, fetal hydrops may ensue, at which point delivery and treatment of the arrhythmia is preferred. However, if the fetus is not at term nor near-term, significant doses of antiarrhythmics may be needed to achieve adequate transplacental bioavailability. Although digoxin has classically been the mainstay of treatment, the use of flecainide or sotalol as monotherapy or in combination with digoxin is being studied. Interdisciplinary team management and shared decision-making between the physician and patient are key to achieving successful outcomes. Adult cardiologists, particularly inpatient consultation services or through burgeoning cardio-obstetrics programs, may, in some practice settings, be asked to evaluate or comanage pregnant women with fetal arrhythmia.

Perioperative Management of Flecainide: A Problem-Based Learning Discussion

Flecainide is a first-line antiarrhythmic drug used to treat atrial arrhythmias and/or supraventricular tachycardia in those without coronary artery disease or structural heart disease. Even though it is an older antiarrhythmic, flecainide accounted for 1.6 million prescriptions in the United States in 2016, and its utilization is generally increasing. Despite its popularity, flecainide may predispose patients to rapid atrial flutter with resultant hemodynamic compromise, particularly in the physiologically stressful perioperative period. This article reviews the pharmacology of flecainide, describes problematic arrhythmias that may arise specifically during flecainide use, and offers recommendations for perioperative flecainide management.

Multiple antiarrhythmic transplacental treatments for fetal supraventricular tachyarrhythmia: A protocol for systematic review and meta analysis

BACKGROUND

Fetal supraventricular tachyarrhythmia is a common reason for referral to fetal cardiology. Multiple antiarrhythmic transplacental medications can be used to treat these diseases. Debates remain regarding the standardized therapy.

METHODS

PubMed, EMBASE, Cochrane Library, Web of Science, Google Scholar, and ClinicalTrials.gov will be searched from inception to September 2020. A handsearching for gray literature, including unpublished conference articles, will be performed. The randomized control trials, case-control, and cohort studies will be accepted, no matter what the languages they were reported. We will first focus on the effectiveness of the therapy on fetal cardiac rhythm and/or heart rate. Then we will do further analysis of preterm delivery, fetal hydrops, intrauterine fetal demise, and maternal side effects. The Cochrane Risk of Bias Tool and the Newcastle-Ottawa scale will be used to assess the risk of bias of the randomized controlled trials, case-control, and cohort studies, respectively. Two independent reviewers will carry out literature identification, data collection, and study quality assessment. Discrepancies will be resolved by a third reviewer. Statistical analysis will be conducted using the STATA 13.0 software.

RESULT

The results will provide helpful information about the effect of multiple antiarrhythmic transplacental therapies in pregnancies with supraventricular tachycardia or atrial flutter, and demonstrate which therapy is more effective.

CONCLUSION

The conclusion drawn from this systematic review will benefit the patients with fetal supraventricular tachyarrhythmia.

Neonatal Arrhythmia

Arrhythmias are seldom observed in the newborn period and rarely lead to serious consequences. Because they may be a continuation of fetal arrhythmias, newborn arrhythmias are different from those occurring at later ages. Here we describe a case of a newborn presented with tachycardia at birth. A female baby of 1950 grams born by emergency cesarean section for fetal distress at 36 weeks of gestation. Fetal tachycardia of 251 bpm was detected prenatally. Electrocardiography showed supraventricular tachycardia (SVT). Hematological and biochemical tests done were within normal limits. Echocardiography revealed normal anatomy with severe tachycardia, dilated chambers with moderate to severe TR with moderately reduced ventricle function. For persisting SVT intravenous adenosine was administered with no significant decrease in heart rate, then continuous intravenous amiodarone infusion was started resulting in a transient decrease in heart rate, however again increased, hence baby was started on intravenous digoxin which responded well. Repeated echocardiography showed normal cardiac chambers and function. Baby was discharged on maintenance oral digoxin and was gradually weaned and stopped after 12 months of age. Neonatal arrhythmias is not an uncommon condition in newborns, however it should be early recognized and evaluated for a better outcome of the baby. Although the frequency of arrhythmias in the newborn period is not high, SVT are the most frequently observed arrhythmias in this period.

Resolution of Fetal Hydrops Dependent on Sustained Fetal Supraventricular Tachycardia after Digoxin Therapy

We present a special case of fetal supraventricular tachycardia detected at 34 weeks gestation. Fetal hydrops was noted on ultrasound upon admission. Normal fetal heart rate was maintained for three weeks by maternal administration of digoxin. A live infant was delivered via caesarian section at 37 weeks gestation. This clinical case demonstrated that pharmacological treatment can be effective and helps to prolong pregnancy safely.

Sotalol as an effective adjunct therapy in the management of supraventricular tachycardia induced fetal hydrops fetalis

Sustained fetal supraventricular tachycardia (SVT) complicated by hydrops fetalis carries a significant risk of morbidity and mortality. While there is no clear consensus on first- and second-line therapy options for the management of fetal SVT with or without hydrops fetalis, there exists significant nonrandomized experience with a number of antiarrhythmic agents that has founded the basis for management. Furthermore, recently published meta-analyses and ongoing multicenter prospective studies have aimed to bridge the gap in the literature. We report two cases of sustained fetal SVT with severe secondary hydrops fetalis managed successfully with flecainide-sotalol combination therapy in one case and sotalol-digoxin combination therapy in the second and review the literature for the management of fetal SVT.

Successful intraosseous adenosine administration in a newborn infant with supraventricular tachycardia

BACKGROUND

Supraventricular tachycardia (SVT) is the most common type of tachycardia in childhood. The incidence is 1-4/1000 in childhood and 0.6/1000 in newborns.

CASE

Here we report a 28-day-old male newborn who was diagnosed SVT, admitted to the Pediatric Emergency Department after restlessness that had started three hours before admission and measurement of the heart rate was above 250 beats/min.

CONCLUSIONS

This case is presented in order to emphasize that SVT is rare in the neonatal period and SVT is successfully terminated with the administration of intraosseous adenosine.

[Drug-induced ventricular dissynchrony and tachycardiomyopathy in a newborn]

Ventricular dysfunction secondary to electrical and mechanical dyssynchrony in chronic right ventricular apical pacing is a well-recognized complication. There are no previous reports of pharmacologically induced dyssynchrony. A 10-day old infant with incessant supraventricular tachycardia was admitted to the neonatal intensive care unit. Therapy with oral propranolol was initiated and due to persistence of tachycardia intravenous amiodarone was administered. The patient remained predominantly in tachycardia with heart rates between 200-290 beats per minute for a week with serial echocardiograms showing preserved ventricular function. Oral flecainide was started. After 24 hours of treatment the patient developed a slower incessant wide QRS with a left bundle branch block pattern. The echocardiogram showed deterioration of left ventricular systolic function and moderate mitral regurgitation. Flecainide and propranolol were discontinued. The QRS complex narrowed and despite intermittent breakthroughs of supraventricular tachycardia, ventricular function normalized. Propranolol was restarted to achieve definitive control of the tachycardia. The presence of ventricular dyssynchrony generated by the left bundle branch block pattern secondary to pharmacological treatment with flecainide is a novel possible explanation for the development of ventricular dysfunction.

Efficacy and safety of 1C class antiarrhythmic agent (propafenone) for supraventricular arrhythmias in septic shock compared to amiodarone: protocol of a prospective randomised double-blind study

INTRODUCTION

Supraventricular arrhythmias contribute to haemodynamic compromise in septic shock. A retrospective study generated the hypothesis that propafenone could be more effective than amiodarone in achieving and maintaining sinus rhythm (SR). Certain echocardiographic parameters may predict a successful cardioversion and help in the decision on rhythm or rate control strategy.

METHODS AND ANALYSIS

The trial includes septic shock patients with new-onset arrhythmia, but without severe impairment of the left ventricular ejection fraction. After baseline echocardiography, the patient is randomised to receive a bolus and maintenance dose of either amiodarone or propafenone. The primary outcome is the proportion of patients that have achieved rhythm control at 24 hours after the start of the infusion. The secondary outcomes are the percentages of patients that needed rescue treatments (DC cardioversion or unblinding and crossover of the antiarrhythmics), the recurrence of arrhythmias, intensive care unit mortality, 28-day and 1-year mortality. In the posthoc analysis, we separately assess subgroups of patients with pulmonary hypertension and right ventricular dysfunction. In the exploratory part of the study, we assess whether the presence of a transmitral diastolic A wave and its higher velocity-time integral is predictive for the sustainability of mechanical SR and whether the indexed left atrial endsystolic volume is predictive of recurrent arrhythmia. Considering that the restoration of SR within 24 hours occurred in 74% of the amiodarone-treated patients and in 89% of the patients treated with propafenone, we plan to include 200 patients to have an 80% chance to demonstrate the superiority of propafenone at p=0.05.

ETHICS AND DISSEMINATION

The trial is recruiting patients according to its second protocol version approved by the University Hospital Ethical Board on the 6 October 2017 (No. 1691/16S-IV). The results will be disseminated through peer reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

NCT03029169.

Fascicular tachycardia in infancy and the use of verapamil: a case series and literature review

OBJECTIVE

Guidelines state that verapamil is contraindicated in infants. This is based on reports of cardiovascular collapse and even death after rapid intravenous administration of verapamil in infants with supraventricular tachycardia (SVT). We wish to challenge this contraindication for the specific indication of verapamil sensitive ventricular tachycardia (VSVT) in infants.

DESIGN

Retrospective case series and critical literature review.

SETTING

Hospitals within New Zealand.

PATIENTS

We present a series of three infants/young children with VSVT or 'fascicular VT'.

RESULTS

Three children aged between 8 days and 2 years presented with tachycardia 200-220 beats per minute with right bundle brunch block and superior axis. Adenosine failed to cardiovert and specialist review diagnosed VSVT. There were no features of cardiovascular shock. Verapamil was given as a slow infusion over 10-30 min (rather than as a push) and each successfully cardioverted without incident. Critical review of the literature reveals that cardiovascular collapses were associated with a rapid intravenous push in cardiovascularly compromised infants and/or infants given other long-acting antiarrhythmics prior to verapamil.

CONCLUSIONS

Verapamil is specifically indicated for the treatment of fascicular VT, and for this indication should be used in infancy, as well as in older children, as first-line treatment or after failure of adenosine raises suspicion of the diagnosis. We outline how to distinguish this tachycardia from SVT and propose a strategy for the safe intravenous slow infusion of verapamil in children, noting that extreme caution is necessary with pre-existing ventricular dysfunction.