Clinical Presentation of Pediatric Patients at Risk for Sudden Cardiac Arrest

An Atypical Anomalous Aortic Origin of the Left Coronary Artery With Intra-Arterial Wall Course Pretending a Normal Migration on Imaging Screening: A Case Report

Background

An anomalous aortic origin of a coronary artery (AAOCA) has been considered as a dominant cause of sudden cardiac death (SCD) among young age children. Therefore, it is critical to identify AAOCA timely to avoid lethal events. Recently, accumulating cases of right or left coronary arteries originating from inappropriate locations at the sinus of Valsalva have been identified. Here, we report a rare case of AAOCA with an intra-arterial wall course pretending normal migration on imaging screening in a patient who suffered from syncope.

Case summary

A 7-year-old male without a previous history of cardiovascular and cerebrovascular diseases suddenly suffered from sharp chest pain and syncope after intensive exercise. The electrocardiogram showed that the ST segment of multiple leads was depressed by more than 0.05 mV, and biomarkers indicated severe myocardial injuries. The left ventricular ejection fraction (LVEF) decreased dramatically to 23%. Fulminant myocarditis and cardiomyopathy were therefore excluded. However, a relatively normal coronary artery origin, which arose from the left coronary sinus, presented on echocardiography and cardiac CT angiography (CTA). It is difficult to draw an association between severe clinical manifestations and slight malformations on echocardiography and CTA. Furthermore, selective coronary angiography revealed that an anomalous left coronary artery arose from the superior margin of the inappropriate sinus, developed an intramural wall course and finally exits the left sinus of Valsalva and migrated between the aorta and the pulmonary artery, which induced severe myocardial infarction during exercise. Then, the patient received surgical correction with a modified unroofing procedure. After 2 months of intensive treatment, the patient was discharged and remained asymptomatic through 18 months of follow-up.

Conclusion

AAOCA, especially anomalous left coronary artery (ALCA), represents a major potential risk of SCD. We reported an atypical manifestation of ALCA arising from the inappropriate sinus of Valsalva and merging into the intra-arterial wall to develop a strange course and then sprout between the aorta and the pulmonary artery. The diversity of AAOCA might present as a relatively normal course under non-invasive radiological imaging scanning.

Impact of genetic tests on survivors of paediatric sudden cardiac arrest

OBJECTIVE

To retrospectively investigate the clinical spectrum, genetic profiles and outcomes of survivors of paediatric sudden cardiac arrest (SCA).

DESIGN AND PATIENTS

All 66 patients (aged 1-20 years), with unexpected SCA or syncope related to ventricular tachycardia (VT)/fibrillation and who survived to discharge from a tertiary centre, were enrolled from 1995 to 2018. Of these, 30 with underlying diseases prior to the events were excluded. Whole-exome sequencing targeting 384 channelopathy and cardiomyopathy-related genes (composite panel) was conducted to identify the possible genetic variants/mutations.

RESULTS

A total of 36 patients were enrolled. Male adolescents predominated (66.7%), and the median age at onset was 13.3 years. Events occurred most often during exercise and daily activities. The yield rate of the genetic test was 84.6% (22/26); 14 had pathogenic variants; and 8 had likely pathogenic variants. The most common diagnoses were long QT in nine (25%), catecholaminergic polymorphic VT in six patients (16.7%), but other long QT and cardiomyopathy genes were also detected in eight patients (30.7%). The 10-year transplantation-free survival rate was 87.8% and was better for those who received genetic tests initially at the disease onset. An implantable cardioverter-defibrillator was implanted in 55.6% of the patients, with an appropriate shock rate of 61.1%. The defibrillator shock rate was lower for those who received composite panel initially.

CONCLUSION

Survivors of SCA in the paediatric population had favourable long-term outcomes aided by genetic test. A broad composite genetic panel brings extra diagnostic value in the investigation of ventricular fibrillation/sudden cardiac death.

Outcomes of Implantable Loop Monitoring in Patients <21 Years of Age

Rhythm-symptom correlation in pediatric patients with syncope/palpitations or at risk cohorts can be difficult, but important given potential associations with treatable or malignant arrhythmia. We sought to evaluate the use, efficacy and outcomes of implantable loop recorders (ILR) in pediatrics. We conducted a retrospective study of pediatric patients (<21 years) with implanted ILR. Patient/historical characteristics and ILR indication were obtained. Outcomes including symptom documentation, arrhythmia detection and ILR based changes in medical care were identified. Comparison of outcomes were performed based on implant indication. Additional sub-analyses were performed in syncope-indication patients comparing those with and without changes in clinical management. A total of 116 patients with ILR implant were identified (79 syncope/37 other). Symptoms were documented 58% of patients (syncope 68% vs nonsyncope 35%; p = 0.002). A total of 37% of patients had a documented clinically significant arrhythmia and 25% of patients had a resultant change in clinical management independent of implant indication. Arrhythmia type was dependent on implant indication with nonsyncope patients having more ventricular arrhythmias. Pacemaker/defibrillator implantation and mediation management were the majority of the clinical changes. In conclusion, IRL utilization in selected pediatric populations is associated with high efficacy and supports clinical management. ILR efficacy is similar regardless of indication although patients with nonsyncope indications had a higher frequency of ventricular arrhythmias as opposed to asystole and heart block in syncope indications. The majority of arrhythmic findings occurred in the first 12 months, and new technology that would allow for less invasive monitoring for 6 to 12 months may be of value.

Outcomes of Pediatric Patients With Defibrillators Following Initial Presentation With Sudden Cardiac Arrest

BACKGROUND

Implantable cardioverter defibrillators (ICD) are recommended for secondary prevention after sudden cardiac arrest (SCA). The outcomes of pediatric patients receiving an ICD after SCA remain unclear. The objective of this study is to evaluate outcomes, future risk for appropriate shocks, and identify characteristics associated with appropriate ICD therapy during follow-up.

METHODS

Multicenter retrospective analysis of patients (age ≤21 years) without prior cardiac disease who received an ICD following SCA. Patient/device characteristics, cardiac function, and underlying diagnoses were collected, along with SCA event characteristics. Patient outcomes including complications and device therapies were analyzed.

RESULTS

In total, 106 patients were included, median age 14.7 years. Twenty (19%) received appropriate shocks and 16 (15%) received inappropriate shocks (median follow-up 3 years). First-degree relative with SCA was associated with appropriate shocks (P<0.05). In total, 40% patients were considered idiopathic. Channelopathy was the most frequent late diagnosis not made at time of presentation. Neither underlying diagnosis nor idiopathic status was associated with increased incidence of appropriate shock. Monomorphic ventricular tachycardia (hazard ratio, 4.6 [1.2-17.3]) and family history of sudden death (hazard ratio, 6.5 [1.4-29.8]) were associated with freedom from appropriate shock in a multivariable model (area under the receiver operating characteristic curve, 0.8). Time from diagnoses to evaluation demonstrated a nonlinear association with freedom from appropriate shock (P=0.015). In patients >2 years from implantation, younger age (P=0.02) and positive exercise test (P=0.04) were associated with appropriate shock.

CONCLUSIONS

The risk of future device therapy is high in pediatric patients receiving an ICD after SCA, irrelevant of underlying disease. Lack of a definitive diagnosis after SCA was not associated with lower risk of subsequent events and does not obviate the need for secondary prophylaxis.

Symptoms and healthcare contact preceding sudden cardiac death in persons aged 1-49 years

Sudden Cardiac Death (SCD) is a leading cause of death among persons in their youth and early middle-age. To prevent SCD it is crucial to identify persons at high-risk of SCD. Knowledge of symptoms and medical contact prior to SCD could potentially aid in the identification of high-risk persons in the general population who would benefit from further investigation. This review aims to summarize the current knowledge of symptoms and healthcare contact preceding SCD in persons aged 1-49 years, and to explore how the symptoms differ according to SCD cause and age of the deceased. There was a high frequency of both cardiac and non-specific symptoms prior to SCD. Additionally, many SCD victims contacted the healthcare system prior to death on the basis of their symptoms and only a few were diagnosed with cardiovascular disease. This information underlines that young persons reporting potential cardiac symptoms should also be thoroughly examined. Furthermore, such symptoms could be used in combination with other easily accessible information in non-invasive prediction models aiming at identifying persons at high risk of SCD that would benefit from further investigation and possibly treatment.

Genetic testing and cascade screening in pediatric long QT syndrome and hypertrophic cardiomyopathy

BACKGROUND

The efficacy of cascade screening for the inherited heart conditions long QT syndrome (LQTS) and hypertrophic cardiomyopathy (HCM) is incompletely characterized.

OBJECTIVE

The purpose of this study was to examine the use of genetic testing and yield of cascade screening across diverse regions in the United States and to evaluate obstacles to screening in multipayer systems.

METHODS

An institutional review board-approved 6 United States pediatric center retrospective chart review of LQTS and HCM patients from 2008-2014 was conducted for (1) genetic test completion and results and (2) family cascade screening acceptance, methods, results, and barriers.

RESULTS

The families of 315 index patients (mean age 9.0 ± 5.8 years) demonstrated a 75% (254) acceptance of cascade screening. The yield of relative screening was 39% (232/601), an average of 0.91 detected per family. Genetic testing was less utilized in HCM index patients and relatives. Screening participation was greater in families of gene-positive index patients (88%) (P <.001) compared to gene-negative patients (53%). Cascade method utilization: Cardiology-only 45%, combined genetic and cardiology 39%, and genetic only 16%. Screening yield by method: combined 57%, genetic-only 29%, and cardiology-only 20%. Family decisions were the leading barriers to cascade screening (26% lack of followthrough and 26% declined), whereas insurance (6%) was the least cited barrier.

CONCLUSION

Family participation in cascade screening is high, but the greatest barriers are family mediated (declined, lack of followthrough). Positive proband genetic testing led to greater participation. Cardiology-only screening was the most utilized method, but combined cardiology and genetic screening had the highest detection.

Catecholaminergic polymorphic ventricular tachycardia managed as orthostatic dysregulation and epilepsy in 11- and 15-year-old sisters

BACKGROUND

In pediatric patients, syncope commonly occurs as vasovagal syncope, or in epilepsy or orthostatic dysregulation. Cardiogenic syncope is rare but it is lethal, and needs to be promptly diagnosed and treated.

METHODS AND RESULTS

We describe the cases of 11- and 15-year-old sisters with frequent syncope during exercise and emotional stress since the age of 10 and 12, respectively. There were no abnormalities on 12-lead electrocardiogram (ECG) at rest. They were first diagnosed with orthostatic dysregulation and epilepsy. Because of recurrent exercise-induced syncope, cardiac examinations were performed. On treadmill exercise stress test, bidirectional ventricular tachycardia was induced in the 11-year-old girl, which degenerated into ventricular fibrillation; frequent polymorphic premature ventricular contractions were induced in her elder sister. They were diagnosed with catecholaminergic polymorphic ventricular tachycardia (CPVT) and started on oral beta-blockers and exercise restriction.

CONCLUSIONS

It is important to suspect CPVT in pediatric exercise-induced syncope, and to recognize that CPVT does not show ECG abnormalities at rest.

Considerations for Assessing the Appropriateness of High-Cost Pediatric Care in Low-Income Regions

It may be difficult to predict the consequences of provision of high-cost pediatric care (HCC) in low- and middle-income countries (LMICs), and these consequences may be different to those experienced in high-income countries. An evaluation of the implications of HCC in LMICs must incorporate considerations of the specific context in that country (population age profile, profile of disease, resources available), likely costs of the HCC, likely benefits that can be gained versus the costs that will be incurred. Ideally, the process that is followed in decision making around HCC should be transparent and should involve the communities that will be most affected by those decisions. It is essential that the impacts of provision of HCC are carefully monitored so that informed decisions can be made about future provision medical interventions.

Sudden Cardiac Death in Children and Adolescents

Sudden cardiac death (SCD) is a rare but devastating event in children and adolescents. Etiologies include congenital heart disease, cardiomyopathies, primary arrhythmia syndromes, and miscellaneous conditions. Challenges in the diagnosis and prevention of SCD in the young are reviewed.

The evaluation of adolescent chest pain: a screening ECG or PSC-17?

PURPOSE OF REVIEW

The present review offers an update on entities presenting as chest pain in the adolescent population. It discusses recently proposed tools and shared mental models used in primary and urgent care settings to evaluate chest pain, and their focus on identifying life-threatening processes. We consider whether the current practice may be improved by accounting for the increasingly recognized non-life-threatening causes of adolescent chest pain.

RECENT FINDINGS

The present experiences and behaviors of adolescents have added new causes of chest pain to the work-up of this disquieting chief complaint. The initial approach to adolescent chest pain has classically focused on ruling out life-threatening entities, and current diagnostic algorithms offer systematic approaches with similar emphases. A growing body of literature on the nonlife-threatening causes of adolescent chest pain, often categorized as idiopathic, suggests a need to reevaluate our practice.

SUMMARY

Adolescent chest pain is most often noncardiac and non-life threatening in nature, yet current diagnostic algorithms and evaluations emphasize identifying the exceptional case of cardiac chest pain. Familiarizing ourselves with the more common causes of chest pain and with our present approach to the evaluation of this particular chief complaint, may help us to better counsel our patients and avoid unnecessary use of valuable resources.

Avoiding sports-related sudden cardiac death in children with congenital channelopathy : Recommendations for sports activities

For the past few years, children affected by an inherited channelopathy have been counseled to avoid (recreational) sports activities and all competitive sports so as to prevent exercise-induced arrhythmia and sudden cardiac death. An increased understanding of the pathophysiological mechanisms, better anti-arrhythmic strategies, and, in particular, more epidemiological data on exercise-induced arrhythmia in active athletes with channelopathies have changed the universal recommendation of "no sports," leading to revised, less strict, and more differentiated guidelines (published by the American Heart Association/American College of Cardiology in 2015). In this review, we outline the disease- and genotype-specific mechanisms of exercise-induced arrhythmia; give an overview of trigger-, symptom-, and genotype-dependent guidance in sports activities for children with long QT syndrome (LQTS), Brugada syndrome (BrS), catecholaminergic polymorphic ventricular tachycardia (CPVT), or short QT syndrome (SQTS); and highlight the novelties in the current guidelines compared with previous versions. While it is still recommended for patients with LQT1 and CPVT (even when asymptomatic) and all symptomatic LQTS patients (independent of genotype) to avoid any competitive and high-intensity sports, other LQTS patients successfully treated with anti-arrhythmic therapies and phenotype-negative genotype-positive patients may be allowed to perform sports at different activity levels - provided they undergo regular, sophisticated evaluations to detect any changes in arrhythmogenic risk.

The renal plumbing system: aquaporin water channels

Aquaporins are channels that facilitate movement of water across lipid bilayers. They are expressed in multiple tissues and are essential for regulation of body water homeostasis. The kidney is the main organ responsible for this regulation, and at least seven aquaporins are expressed at distinct sites in the kidney. Aquaporin expression correlates with observed water permeability of each nephron segment: proximal tubule and descending thin limb of Henle have constitutive high water permeability due to expression of AQP1, whereas collecting duct water permeability is tightly regulated by the antidiuretic hormone vasopressin via regulation of AQP2. This review aims at providing insight into renal aquaporins, with special focus on AQP2.