International Cohort of Neonatal Timothy Syndrome.

INTRODUCTION: Timothy syndrome (TS) is an extremely rare, multisystem disorder classically associated with long QT, syndactyly, ventricular arrhythmias, and hypoglycaemia. A neonatal diagnosis allows maximal medical and device therapy to be implemented to avoid malignant arrhythmias and sudden cardiac death. METHODS: This was a retrospective case series study of type I TS (TS1) patients using data from the Timothy Syndrome Foundation's international registry, encompassing patients with a genetic diagnosis (CACNA1C variant G406R in exon 8A) recruited over a 28-year period. RESULTS: Forty-four cases of TS1 were included (26 male; 60%). Mean gestational age (GA) was 35.6 weeks (range 28 weeks - term), with 43% of patients born less than 37 weeks GA. In TS1 patients presenting with foetal bradycardia, mean GA was significantly lower (34.2 weeks, p < 0.05). Foetal bradycardia secondary to atrioventricular block was present in 20 patients (45%), resulting in premature delivery in 14 patients (32%). Fifteen patients (34%) were diagnosed with TS1 as neonates. Long QT at birth helped secure a diagnosis in 25 patients (57%). Syndactyly was seen in most patients (n = 40, 91%). Twenty patients died, with an average age of death of 2.3 years (range 1 month-6 years). Of the 7 patients who died before the first year of life (16%), the average age of death was 2.5 months. CONCLUSION: TS is associated with high early mortality. TS should be considered in paediatric patients presenting with long QT and syndactyly. Recognition of TS in the neonatal period allows for early intervention to prevent life-threatening arrhythmias.

Preliminary assessment of paediatric electrophysiology cardiac implantable electronic device resources around the world.

BACKGROUND: The Pediatric and Congenital Electrophysiology Society (PACES) is a global organisation committed to the care of children and adults with CHD and arrhythmias. OBJECTIVE: To evaluate the global needs and potential inequities as it relates to cardiac implantable electronic devices. METHODS: ARROW (Assessment of Rhythm Resources arOund the World) is an online survey about cardiac implantable electronic devices, sent electronically to physicians within the field of Cardiology, Pediatric Cardiology, Electrophysiology and Pediatric Electrophysiology. RESULTS: ARROW received 42 responders from 28 countries, 50% from low-/middle-income regions. The main differences between low-/middle- and high-income regions include availability of expertise on paediatric electrophysiology (50% versus 93%, p < 00.5) and possibility to perform invasive procedures (35% versus 93%, p < 0.005). Implant of devices in low-income areas relies significantly on patient's resources (71%). The follow-up of the devices is on the hands of paediatric cardiologist/electrophysiologist in higher resources centres (93% versus 50%, p < 0.05). CONCLUSIONS: The ARROW survey represents an initial assessment of the geographical characteristics in the field of Pediatric Electrophysiology. The next step is to make this "state of the art" more extensive to other aspects of the expertise. The relevance of collecting this data before the World Congress of Pediatric Cardiology and Cardiac Surgery (WCPCCS) in 2023 in Washington DC was emphasised in order to share the resulting information with the international community and set a plan of action to assist the development of arrhythmia services for children within developing regions of the world.

2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients: Developed in collaboration with and endorsed by the Heart Rhythm Society (HRS), the American College of Cardiology (ACC), the American Heart Association (AHA), and the Association for European Paediatric and Congenital Cardiology (AEPC) Endorsed by the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS).

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.

2021 PACES expert consensus statement on the indications and management of cardiovascular implantable electronic devices in pediatric patients.

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.

2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients.

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.

2021 PACES expert consensus statement on the indications and management of cardiovascular implantable electronic devices in pediatric patients: Executive summary.

Guidelines for the implantation of cardiac implantable electronic devices (CIEDs) have evolved since publication of the initial ACC/AHA pacemaker guidelines in 1984 [1]. CIEDs have evolved to include novel forms of cardiac pacing, the development of implantable cardioverter defibrillators (ICDs) and the introduction of devices for long term monitoring of heart rhythm and other physiologic parameters. In view of the increasing complexity of both devices and patients, practice guidelines, by necessity, have become increasingly specific. In 2018, the ACC/AHA/HRS published Guidelines on the Evaluation and Management of Patients with Bradycardia and Cardiac Conduction Delay [2], which were specific recommendations for patients >18 years of age. This age-specific threshold was established in view of the differing indications for CIEDs in young patients as well as size-specific technology factors. Therefore, the following document was developed to update and further delineate indications for the use and management of CIEDs in pediatric patients, defined as ≤21 years of age, with recognition that there is often overlap in the care of patents between 18 and 21 years of age. This document is an abbreviated expert consensus statement (ECS) intended to focus primarily on the indications for CIEDs in the setting of specific disease/diagnostic categories. This document will also provide guidance regarding the management of lead systems and follow-up evaluation for pediatric patients with CIEDs. The recommendations are presented in an abbreviated modular format, with each section including the complete table of recommendations along with a brief synopsis of supportive text and select references to provide some context for the recommendations. This document is not intended to provide an exhaustive discussion of the basis for each of the recommendations, which are further addressed in the comprehensive PACES-CIED document [3], with further data easily accessible in electronic searches or textbooks.

2021 PACES expert consensus statement on the indications and management of cardiovascular implantable electronic devices in pediatric patients.

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.

Ventricular Arrhythmia and Life-Threatening Events in Patients With Repaired Tetralogy of Fallot.

Risk stratification for malignant arrhythmias and risk of sudden cardiac death in tetralogy of Fallot (TOF) remains challenging. We aimed to ascertain factors associated with life-threatening arrhythmic events. A multicenter retrospective case-control study including 72 TOF patients with documented cardiac arrest and/or sustained ventricular tachycardia, compared with 216 controls matched for era of surgery. The mean age at event in the cases was 27.3 ± 12.5 years. The majority (57%) presented with sustained ventricular tachycardia. Fatal events occurred in 9. Random forest analysis and a decision tree demonstrated surgical era specific risk factors (< vs ≥ 1980). For both eras, arrhythmic symptoms and left ventricular dysfunction were strongly associated with malignant arrhythmias. In addition, right ventricular dysfunction and age at repair ≥ 6.5 years preceded by a shunt were associated with a higher risk group in the early era, whereas a trans-annular patch type repair was associated with a lower risk group in the recent era. For the moderate and high-risk groups, the decision tree showed a sensitivity of 88.4% and specificity of 68.1%. An "importance factor" was calculated for each predictor, creating a risk score and 4 risk categories. In conclusions, this risk stratification scheme, based on clinical history and noninvasive testing, allows categorization of TOF patients at high risk of malignant arrhythmia. A multicenter prospective evaluation of the accuracy of this scoring system is now being planned.

Quality of life assessment in children before and after a successful ablation for supraventricular tachycardia.

BACKGROUND AND OBJECTIVES: Young patients suffering from rhythm disorders have a negative impact in their quality of life. In recent years, ablation has become the first-line therapy for supraventricular arrhythmias in children. In the light of the current expertise and advancement in the field, we decided to evaluate the quality of life in young patients with supraventricular arrhythmias before and after a percutaneous ablation procedure. METHODS: The prospective cohort consisted of patients <18 years with structurally normal hearts and non-pre-excited supraventricular arrhythmias, who had an ablation in our centre from 2013 to 2018. The cohort was evaluated with the PedsQL™ 4.0 Generic Core Scales self-questionnaire prior to and post-ablation. RESULTS: The final cohort included 88 patients consisted of 52 males (59%), with a mean age at ablation of 12.5 ± 3.3 years. Forty-two patients (48%) had a retrograde-only accessory pathway mediating the tachycardia, 38 (43%) had atrio-ventricular nodal re-entrant tachycardia, 7 (8%) had ectopic atrial tachycardia, and 1 (1%) had atrial flutter. The main reason for an ablation was the patient's choice in 53%. There were no severe complications. Comparison between the baseline and post-ablation assessments showed that patients reported significant improvement in the scores for physical health, emotional and social functioning, as well as in the total scores. CONCLUSIONS: The present study demonstrates that the successful treatment of supraventricular arrhythmias by means of an ablation results in a significant improvement in the quality of self-reported life scores in young patients.

Characterization and Management of Arrhythmic Events in Young Patients With Brugada Syndrome.

BACKGROUND: Information on young patients with Brugada syndrome (BrS) and arrhythmic events (AEs) is limited. OBJECTIVES: The purpose of this study was to describe their characteristics and management as well as risk factors for AE recurrence. METHODS: A total of 57 patients (age ≤20 years), all with BrS and AEs, were divided into pediatric (age ≤12 years; n = 26) and adolescents (age 13 to 20 years; n = 31). RESULTS: Patients' median age at time of first AE was 14 years, with a majority of males (74%), Caucasians (70%), and probands (79%) who presented as aborted cardiac arrest (84%). A significant proportion of patients (28%) exhibited fever-related AE. Family history of sudden cardiac death (SCD), prior syncope, spontaneous type 1 Brugada electrocardiogram (ECG), inducible ventricular fibrillation at electrophysiological study, and SCN5A mutations were present in 26%, 49%, 65%, 28%, and 58% of patients, respectively. The pediatric group differed from the adolescents, with a greater proportion of females, Caucasians, fever-related AEs, and spontaneous type-1 ECG. During follow-up, 68% of pediatric and 64% of adolescents had recurrent AE, with median time of 9.9 and 27.0 months, respectively. Approximately one-third of recurrent AEs occurred on quinidine therapy, and among the pediatric group, 60% of recurrent AEs were fever-related. Risk factors for recurrent AE included sinus node dysfunction, atrial arrhythmias, intraventricular conduction delay, or large S-wave on ECG lead I in the pediatric group and the presence of SCN5A mutation among adolescents. CONCLUSIONS: Young BrS patients with AE represent a very arrhythmogenic group. Current management after first arrhythmia episode is associated with high recurrence rate. Alternative therapies, besides defibrillator implantation, should be considered.

Long-term results of atrial maze surgery in patients with congenital heart disease.

AIMS: Recurrent atrial tachycardia is common after repair of many types of congenital heart disease, and surgical ablation with a maze procedure represents a potential treatment strategy. The objective of this study is to report a single-centre 19 years' experience with maze surgery in congenital heart patients. METHODS AND RESULTS: Patients undergoing maze procedure concomitantly with cardiac surgical procedures were retrospectively analysed. The maze procedure was classified as therapeutic if the patient demonstrated preoperative atrial arrhythmias, or as prophylactic if done because the patient was considered high risk for post-operative arrhythmias. Acute outcomes and longer-term freedom from atrial arrhythmias were analysed. Maze surgery was performed in 166 patients: 137 in the therapeutic group, and 29 in the prophylactic group. The most common congenital heart lesion was single ventricle for the therapeutic group (27%) and Ebstein's anomaly for the prophylactic group (76%). Surgery consisted of a right atrial maze in 63%, left atrial maze in 4%, and bilateral maze in 33%. There were no direct complications or mortality related to the maze procedure itself. For the therapeutic group, freedom from arrhythmias was 82% and 67% at 1 and 5 years post-maze. Younger age at the time of surgery correlated with a lower long-term recurrence risk. CONCLUSION: Maze procedure at the time of an elective anatomic surgery is reasonably effective to prevent and treat atrial arrhythmias in patients with congenital heart disease at short- and mid-term, with low morbidity and mortality.

Efficacy of treatment with belladonna in children with severe pallid breath-holding spells.

IntroductionPallid breath-holding spells are common and dramatic forms of recurrent syncope in infancy. They are very stressful despite their harmless nature and sometimes require treatment. OBJECTIVE: The objective of this study was to evaluate the efficacy of belladonna in severe breath-holding spells. METHODS: This is a multicentric, retrospective series involving 84 children with severe pallid breath-holding spells. Inclusion criteria were >1 pallid breath-holding spell with loss of consciousness, paediatric cardiology evaluation, and follow-up >6 months. In total, 45 patients received belladonna and 39 patients did not receive treatment, according to physician preference. RESULTS: Mean age was 11 months, ranging from 4 to 18 months, with 54% of males. Mean spell duration was 30 seconds (interquartile range 15, 60), and the frequency was four episodes per month (interquartile range 0.5, 6.5). Comparison of baseline characteristics between groups showed similar demographics, with the single difference in the severity of the spells, being more severe in the treated group. When comparing the treated and non-treated groups at 3 months, only two (5%) patients had a complete remission in the first group, whereas 20 (44%) had remission in the belladonna group (p<0.01). When considering the characteristics of the spells before and after the initiation of treatment with belladonna, 75% of the patients presented a positive response, with 44% of the patients presenting with complete resolution of the spells (p<0.01). No major adverse reaction was reported, with only 5% minor adverse events. CONCLUSIONS: Belladonna is highly effective to alleviate severe breath-holding spells in young children, without any major adverse effects.

Implantable Cardioverter-Defibrillators in Children and Adolescents With Brugada Syndrome.

BACKGROUND: Young patients presenting with symptomatic Brugada syndrome have very high risks for ventricular arrhythmias and should be carefully considered for implantable cardioverter-defibrillator (ICD) placement. However, this therapy is associated with high rates of inappropriate shocks and device-related complications. OBJECTIVES: This study investigated clinical features, management, and long-term follow-up of young patients with Brugada syndrome and ICD. METHODS: Patients diagnosed with Brugada syndrome, who underwent implantation of an ICD at an age of ≤20 years, were studied. RESULTS: The study included 35 consecutive patients. The mean age at ICD placement was 13.9 ± 6.2 years. Ninety-two percent were symptomatic; 29% presented with aborted sudden cardiac death and 63% with syncope. During a mean follow-up period of 88 months, sustained ventricular arrhythmias were treated by the ICD in 9 patients (26%), including shocks in 8 patients (23%) and antitachycardia pacing in 1 patient (3%). Three patients (9%) died in an electrical storm. Seven patients (20%) experienced inappropriate shocks, and 5 patients (14%) had device-related complications. Aborted sudden cardiac death and spontaneous type I electrocardiogram were identified as independent predictors of appropriate shock occurrence. CONCLUSIONS: ICD therapy is an effective strategy in young patients with symptomatic Brugada syndrome, treating potentially lethal arrhythmias in >25% of patients during follow-up. Appropriate shocks were significantly associated with previously aborted sudden cardiac death and spontaneous type I electrocardiograms. However, ICDs are frequently associated with complications and inappropriate shocks, both of which remain high regardless of careful device implantation and programming.

A Clinical Score Model to Predict Lethal Events in Young Patients (≤19 Years) With the Brugada Syndrome.

Risk stratification in Brugada syndrome in young patients remains challenging. We investigated the clinical characteristics, prognosis, and risk in young patients with the Brugada syndrome. We studied 95 patients with the Brugada syndrome aged ≤19 years. The median age at diagnosis was 12.9 years. The clinical presentation was sudden cardiac death in 7% and syncope in 21%. The remaining 72% were asymptomatic at diagnosis. Electrical abnormalities were present in 36%, including spontaneous type I electrocardiogram (12%), sinus node dysfunction (9%), atrioventricular block (17%), intraventricular conduction delay (16%), and atrial arrhythmias (8%). An electrophysiologic study was performed in 75%; ventricular arrhythmias were induced in 3%. An implantable cardioverter-defibrillator was placed in 25%. During a mean follow-up of 59 months, 9 patients presented with arrhythmic events (event rate: 1.9% per year). Variables significantly associated with events were: presentation with sudden cardiac death or syncope, spontaneous type I electrocardiogram, sinus node dysfunction and/or atrial tachycardia, conduction abnormality, and induction of ventricular arrhythmias during programmed ventricular stimulation. A model including the previous 4 main clinical variables (1, sudden cardiac death or syncope; 2, spontaneous type I electrocardiogram; 3, sinus node dysfunction and/or atrial tachycardia; and 4, conduction abnormality) had a high predictive power (C: 0.93) for the risk of lethal events. A score of ≥4 conferred a 5-year event probability of 30% that increased to 53% if the score was ≥6. In conclusion, our study validated a model to predict risk in young patients with the Brugada syndrome, which takes into account 4 clinical measures.