Section on Cardiology and Cardiac Surgery. Pediatric sudden cardiac arrest

AAP Recommended Cardiac Screening Questions in Preparticipation Physical Evaluation Forms

To evaluate the utilization of the American Academy of Pediatrics' (AP) cardiovascular screening questions within preparticipation physical evaluation forms from the 50 state high school athletic associations. We found that fewer than half of state forms incorporated all 10 AAP questions; moreover, a subset failed to adhere to criteria recommended by either the AAP or American Heart Association.

Sudden cardiac arrest in infants and children: proposal for a diagnostic workup to identify the etiology. An 18-year multicenter evaluation in the Netherlands

Sudden cardiac arrest (SCA) studies are often population-based, limited to sudden cardiac death, and excluding infants. To guide prevention opportunities, it is essential to be informed of pediatric SCA etiologies. Unfortunately, etiologies frequently remain unresolved. The objectives of this study were to determine paediatric SCA etiology, and to evaluate the extent of post-SCA investigations and to assess the performance of previous cardiac evaluation in detecting conditions predisposing to SCA. In a retrospective cohort (2002-2019), all children 0-18 years with out-of-hospital cardiac arrest (OHCA) referred to Erasmus MC Sophia Children's Hospital or the Amsterdam UMC (tertiary-care university hospitals), with cardiac or unresolved etiologies were eligible for inclusion. SCA etiologies, cardiac and family history and etiologic investigations in unresolved cases were assessed. The etiology of arrest could be determined in 52% of 172 cases. Predominant etiologies in children ≥ 1 year (n = 99) were primary arrhythmogenic disorders (34%), cardiomyopathies (22%) and unresolved (32%). Events in children < 1 year (n = 73) were largely unresolved (70%) or caused by cardiomyopathy (8%), congenital heart anomaly (8%) or myocarditis (7%). Of 83 children with unresolved etiology a family history was performed in 51%, an autopsy in 51% and genetic testing in 15%. Pre-existing cardiac conditions presumably causative for SCA were diagnosed in 9%, and remained unrecognized despite prior evaluation in 13%.

CONCLUSION

SCA etiology remained unresolved in 83 of 172 cases (48%) and essential diagnostic investigations were often not performed. Over one-fifth of SCA patients underwent prior cardiac evaluation, which did not lead to recognition of a cardiac condition predisposing to SCA in all of them. The diagnostic post-SCA approach should be improved and the proposed standardized pediatric post-SCA diagnostics protocol may ensure a consistent and systematic evaluation process increasing the diagnostic yield.

WHAT IS KNOWN

• Arrests in infants remain unresolved in most cases. In children > 1 year, predominant etiologies are primary arrhythmia disorders, cardiomyopathy and myocarditis. • Studies investigating sudden cardiac arrest are often limited to sudden cardiac death (SCD) in 1 to 40 year old persons, excluding infants and successfully resuscitated children.

WHAT IS NEW

• In patients with unresolved SCA events, the diagnostic work up was often incompletely performed. • Over one fifth of victims had prior cardiac evaluation before the arrest, with either a diagnosed cardiac condition (9%) or an unrecognized cardiac condition (13%).

A 12-Year-Old with Sudden Cardiac Arrest

Sudden Cardiac Arrest in 12-Year-Old BoyA 12-year-old boy suddenly lost consciousness while playing catch in his backyard. He was found pulseless and received cardiopulmonary resuscitation and defibrillation before being transferred to the emergency department. How do you approach the evaluation, and what is the diagnosis?

Sudden cardiac death in the young: An update for NPs

NPs can identify risk for sudden cardiac death in children during physical exams to prevent tragedy. The updated American Academy of Pediatrics 2021 policy statement on this issue provides guidance on using a combination of elements to determine and manage risk, including the organization's own 4-question screening tool, the American Heart Association 14-Element Preparticipation Cardiovascular Screening of Young Competitive Athletes, personal history, family history, physical exam, ECG, and cardiology referral as indicated.

Preparticipation State Cardiac Screening Forms for Athletes

BACKGROUND AND OBJECTIVES

Annual preparticipation physical evaluation (PPE) is used in the United States to screen adolescents for potential causes of sudden cardiac death. The American Heart Association recommends 14 screening elements of history and physical examination. This study sought to define the utilization of these screening elements by each of the 50 states before high school athletics.

METHODS

PPE forms were obtained from the public website of the high school athletics governing body in every state. Form content was analyzed to identify which of the 14 screening elements were explicitly fulfilled. Additional PPE forms provided by private/parochial schools, other professional societies, or independent groups were excluded from this study.

RESULTS

A total of 48 states (96%) had PPE forms posted online. The remaining 2 states (4%) deferred the specific method of PPE documentation to individual school districts and provided no standardized form. Of the 48 states providing PPE forms, 13 (27%) included all 14 American Heart Association screening elements. The median criteria included by each state was 11 (range 3-14). The 3 criteria most commonly absent were (1) the examination of femoral pulses to exclude coarctation (58%), (2) a family history of specific inherited cardiac disease (31%), and (3) personal history of hypertension (27%).

CONCLUSIONS

Annual preparticipation forms are important screening tools. Only a minority of states include all 14 cardiac screening elements recommended by the American Heart Association.

Dissemination of Chest Compression-Only Cardiopulmonary Resuscitation by Bystanders for Out-of-Hospital Cardiac Arrest in Students: A Nationwide Investigation in Japan

We aimed to investigate how the types of bystander-initiated cardiopulmonary resuscitation (CPR) for out-of-hospital cardiac arrest (OHCA) among students have changed recently. We also determined the association between two types of bystander-CPRs (i.e., chest compression-only CPR [CCCPR] and conventional CPR with rescue breathing [CCRB]) and survival after OHCA. From a nationwide registry of pediatric OHCAs occurring in school settings in Japan, the data of 253 non-traumatic OHCA patients (elementary, junior high, and high school/technical college students) receiving bystander-CPR between April 2008 and December 2017 were analyzed. Multivariable logistic regression analysis was conducted to assess the impact of different types of bystander-CPR on 30-day survival with favorable neurological outcomes. The proportion of patients receiving CCCPR increased from 25.0% during 2008–2009 to 55.3% during 2016–2017 (p for trend < 0.001). Overall, 53.2% (50/94) of patients receiving CCCPR and 46.5% (74/159) of those receiving CCRB survived for 30 days with favorable neurological outcomes. Multivariable analysis showed no significant difference in outcomes between the two groups (adjusted odds ratio: 1.23, 95% confidence interval: 0.67–2.28). In this setting, CCCPR is a common type of bystander-CPR for OHCA in students, and the effectiveness of CCCPR and CCRB on survival outcomes seems comparable.

[Causes and mechanisms of sudden cardiac death in children]

The paper presents basic morphological criteria of the diagnosis of sudden cardiac death related to different diseases in young people. Attention is drawn to cardiomyopathies, channelopathies, connective tissue dysplasias, Marfan syndrome with cystic medial necrosis, sudden arrhythmic death. Initiating events in sudden cardiac death are discussed. Besides morphological manifestations, the paper dwells upon major genetic events and clinical presentation of the diseases. It is based on both existing publications and own data.

Sudden Death in the Young: Information for the Primary Care Provider

There are multiple conditions that can make children prone to having a sudden cardiac arrest (SCA) or sudden cardiac death (SCD). Efforts have been made by multiple organizations to screen children for cardiac conditions, but the emphasis has been on screening before athletic competition. This article is an update of the previous American Academy of Pediatrics policy statement of 2012 that addresses prevention of SCA and SCD. This update includes a comprehensive review of conditions that should prompt more attention and cardiology evaluation. The role of the primary care provider is of paramount importance in the evaluation of children, particularly as they enter middle school or junior high. There is discussion about whether screening should find any cardiac condition or just those that are associated with SCA and SCD. This update reviews the 4 main screening questions that are recommended, not just for athletes, but for all children. There is also discussion about how to handle post-SCA and SCD situations as well as discussion about genetic testing. It is the goal of this policy statement update to provide the primary care provider more assistance in how to screen for life-threatening conditions, regardless of athletic status.

Deployment of a Clinical Pathway to Improve Postcardiac Arrest Care: A Before-After Study

OBJECTIVES

Postcardiac arrest care bundles following adult cardiac arrest are associated with improved survival to discharge. We aimed to evaluate whether a clinical pathway and computerized order entry were associated with improved pediatric postcardiac arrest care and discharge outcomes.

DESIGN

Single-center retrospective before-after study.

SETTING

Academic PICU.

PATIENTS

Patients who suffered an in- or out-of-hospital cardiac arrest from January 2008 to December 2015 cared for in the PICU within 12 hours of sustained return of circulation.

INTERVENTION

Deployment of a postcardiac arrest clinical pathway and computerized order entry system.

MEASUREMENTS AND MAIN RESULTS

There were 380 patients included-163 in the pre-pathway period and 217 in the post-pathway period. Primary outcome was percent adherence to pathway clinical goals at 0-6 and 6-24 hours post-return of circulation and to diagnostics (continuous electroencephalogram monitoring, head CT for out-of-hospital cardiac arrests, echocardiogram). Secondary outcomes included survival to hospital discharge and survival with favorable neurologic outcome (Pediatric Cerebral Performance Category of 1-3 or no change from baseline). The pre-pathway and post-pathway groups differed in their baseline Pediatric Cerebral Performance Category scores and the following causes of arrest: airway obstruction, arrhythmias, and electrolyte abnormalities. Pathway adherence was not significantly different between the pre-pathway and post-pathway groups, with the exception of higher rates of continuous electroencephalogram monitoring (45% vs 64%; p < 0.001). There was no difference in survival to hospital discharge between the two groups (56% vs 67%; adjusted odds ratio, 1.68; 95% CI, 0.95-2.84; p = 0.05). Survival to discharge was higher in the post-pathway group for the in-hospital cardiac arrest cohort (55% vs 76%; adjusted odds ratio, 3.06; 95% CI, 1.44-6.51; p < 0.01). There was no difference in favorable neurologic outcome between all patients (adjusted odds ratio, 1.21; 95% CI, 0.72-2.04) or among survivors (adjusted odds ratio, 0.72; 95% CI, 0.27-1.43).

CONCLUSIONS

After controlling for known potential confounders, the creation and deployment of a postcardiac arrest care pathway and computerized order entry set were not associated with improvement in pathway adherence or overall outcomes, but was associated with increased survival to hospital discharge for children with in-hospital cardiac arrests.

Incidence, characteristics, and outcomes of pediatric out-of-hospital cardiac arrest in nursery schools and kindergartens in Japan

BACKGROUND

A better understanding of the epidemiology of pediatric out-of-hospital cardiac arrest (OHCA) occurring in nursery schools and kindergartens is indispensable to establish an evidence-based strategy for prevention and improved outcomes. This study aimed to describe the incidence, characteristics, and outcomes of pediatric OHCAs that occurred in certified nursery schools and kindergartens.

METHODS

Stop and Prevent cardIac aRrest, Injury, and Trauma in Schools (SPIRITS) is a study to construct and analyze a nationwide registry of pediatric OHCAs occurring in school settings in Japan. Using data from the SPIRITS registry, we assessed the incidence, characteristics, and outcomes of pediatric OHCAs that occurred in certified nursery schools/kindergartens between April 2008 and December 2016.

RESULTS

During the study period, 37 OHCA patients (31 in certified nursery schools and 6 in kindergartens) were confirmed. The overall incidence rate was 0.13 per 100,000 children per year. Among 37 patients, 57% (21/37) had an OHCA while napping and 35% (13/37) experienced OHCA that was witnessed by bystanders. Although public-access automated external defibrillator pads were applied by bystanders in 24% (9/37) of cases, only 1 patient actually received defibrillation. Overall, the proportion of 1-month survival with favorable neurological outcomes after OHCA was 19% (7/37). Among those with OHCA of non-medical origins, 60% (3/5) of patients experienced arrest caused by suffocation, 60% (3/5) by drowning, and 100% (1/1) by head injury. In contrast, no patient had 1-month favorable neurological outcomes among those with OHCA of medical origins such as presumed cardiac origin (0/17), sudden infant death syndrome (0/6), acute viral myocarditis (0/1), respiratory disease (0/1), and ventricular fibrillation (0/1).

CONCLUSIONS

In this population, the majority of pediatric OHCAs occurring in certified nursery schools/kindergartens had non-ventricular fibrillation rhythm, and their outcomes after OHCA of medical origin were poor.

Study on the Improvement of Electrical Facility System of Automated External Defibrillators by Real-Time Measurement of Thoracic Impedance

Sudden Cardiac Arrest (SCA) is a serious emergency disease that has increased steadily every year. To this end, an Automated External Defibrillator (AED) is placed in a public place so that even non-professional medical personnel can respond to SCA. However, the thoracic impedance of patients changes due to CardioPulmonary Resuscitation (CPR) and artificial respiration during first aid treatment. In addition, changes in chest statues due to gender, age, and accidents cause changes in thoracic impedance in real time. The change in thoracic impedance caused by this has a negative effect on the intended electrical energy of the automatic heart shocker to the emergency patient. To prove this, we divided it into adult and pediatric modes and experimented with the energy error of the AED according to the same impedance change. When the first peak current was up to 56.4 (A) and at least 8.4 (A) in the adult mode, the first peak current was up to 32.2 (A) and at least 4.8 (A), respectively, when the impedance changed, the error of the current figure occurred. In this paper, the inverse relationship between thoracic impedance and electric shock energy according to the state of the cardiac arrest patient is demonstrated through the results of the experiment, and the need for an electric facility system that can revise for changes in thoracic impedance of the cardiac arrest patient by reflecting them on electric shock energy in real time is presented.

Can Pediatric Practitioners Correctly Interpret Electrocardiograms?

OBJECTIVES

To assess the impact of participation in an educational presentation on electrocardiogram (ECG) interpretation in children on pediatric practitioners' ability to accurately interpret ECGs.

STUDY DESIGN

Pediatric healthcare providers at a pediatric clinic with >65 000 visits/year were eligible to participate. A 1-hour ECG educational module that provided a systematic approach to ECG interpretation was presented to 8 providers who consented (6 pediatricians, 2 pediatric nurse practitioners). A test on 11 ECGs (normal, normal-variant, and abnormal ECGs) was given before and 2 weeks after the educational module. Outcomes included correct interpretation of each ECG as normal or abnormal and correct identification of specific ECG findings. Data analysis was descriptive and included χ² and Student t test.

RESULTS

Mean score (SD) for correct interpretation of ECGs as normal or abnormal improved from 35% (48%) (95% CI 25.0-45.4) to 77% (42%) (95% CI 68.3-86.2) after the ECG educational module (P < .001). Mean (SD) pretest score for correct identification in the normal ECG category improved from 45% (50%) (95% CI 28.9-61.1) to 68% (47%) (95% CI 52.3-82.7) (P= .003). In the abnormal ECG category, correct identification improved from 31% (47%) (95% CI 17.6-44.9) to 83% (5%) (95% CI 72.4-94.3) after the module (P < .001).

CONCLUSIONS

Education of pediatric practitioners on ECG interpretation significantly improves their ability to distinguish normal from abnormal and to identify specific abnormalities. Limitations included small sample size and short-term follow-up.

Cardiovascular Clearance for Sports Participation

Sudden cardiac death (SCD) in a young athlete is a rare but tragic occurrence. The goal of this article is to provide information about the risks of sudden cardiac death in athletes by reviewing the epidemiology and describing the current screening recommendations of the American Heart Association/American College of Cardiology. ¹ The specifics of and reasons for differences between screening guidelines in the United States and the screening guidelines in Europe are highlighted. Electrocardiogram (ECG) changes that can be expected in the setting of conditioning vs pathology are described. Intrinsic cardiac pathologies and disorders, with related cardiac findings, are reviewed, including prevalence and inheritance patterns. Also included is a brief medical-legal discussion about physician liability in the course of making sports clearance decisions. In an area in which there is no single national standard but in which there is an expectation by almost all states for a clearance examination, this article aims to help physicians make thoughtful decisions when evaluating a seemingly healthy patient in order to detect those rare athletes who may be at increased risk of succumbing to a sudden cardiac death during sports participation. ²¹.

Epidemiology of Pediatric Out-of-Hospital Cardiac Arrest at School - An Investigation of a Nationwide Registry in Japan

BACKGROUND

A better understanding of the epidemiology of pediatric out-of-hospital cardiac arrest (OHCA) occurring in school settings is important to establish an evidence-based strategy for prevention and better prognosis.Methods and Results:The Stop and Prevent cardIac aRrest, Injury, and Trauma in Schools (SPIRITS) is a nationwide prospective observational study linking databases from 2 nationally representative registries, the Injury and the Accident Mutual Aid Benefit System of The Japan Sport Council and the All-Japan Utstein Registry of the Fire and Disaster Management Agency. Using these databases, we described the detailed characteristics and outcomes of pediatric OHCAs that occurred in school settings in Japan between 2009 and 2014. During the 6-year study period, 295 OHCA cases were confirmed. Overall incidence rate was 0.4 per 100,000 students per year. The majority of OHCA cases had a cardiac origin (71%), occurred during exercise (65%), were witnessed by bystanders (70%), and received bystander-initiated cardiopulmonary resuscitation (73%). In approximately one-third of cases the student was defibrillated by public-access automated external defibrillator (38%). The proportion of patients with 1-month survival and a favorable neurological outcome was 34% among all OHCAs and 43% among OHCAs of cardiac origin.

CONCLUSIONS

In Japan, approximately 50 pediatric cases of OHCA consistently occur yearly in school settings. The majority of students received basic life support from bystanders, and patients with OHCA of cardiac origin had a relatively good prognosis.

Sudden unexpected cardio-respiratory arrest after venipuncture in children

Purpose

This study aimed to investigate the clinical and socioenvironmental characteristics of sudden cardiorespiratory arrest after venipuncture in children.

Methods

We conducted a retrospective email-based survey of all members of the Korean Pediatric Society. The questionnaire included items on patient demographics, socioenvironmental circumstances of the venipuncture, type of cardiorespiratory arrest, symptoms and signs, treatment, prognosis, and presumed cause of the arrest.

Results

Fourteen patients were identified. Of these, 13 were young children (<2 years old), and 1 was 14 years old. All patients had been previously healthy and had no specific risk factors for sudden cardiorespiratory arrest. Most cases (n=11, 79%) were defined as cardiac or cardiorespiratory arrest, while the remaining cases (n=3, 21%) were defined as respiratory arrest. Aspiration (n=3), acute myocarditis (n=2), and laryngeal chemoreflex (n=1) were presumed as the causes; however, the exact causes were unclear. The overall prognosis was poor (death, n=7; morbidity, n=5; full recovery, n=2). The medical institutions faced severe backlash because of these incidents (out-of-court settlement, n=5; medical lawsuit, n=5; continuous harassment, n=3).

Conclusion

Cardiorespiratory arrest after venipuncture is unpredictable and the probable cause of most cases is a vasovagal reaction. Medical personnel must be aware of the risk of unexpected cardiorespiratory arrest during routine intravenous procedures.

The influence of targeted temperature management on the pharmacokinetics of drugs administered during and after cardiac arrest: a systematic review

OBJECTIVE

Pharmacokinetic parameters of drugs are widely investigated under normothermic conditions and normal hemodynamic parameters. The European Resuscitation Council recommends the use of targeted temperature management (TTM) with a target temperature of 34 °C in cardiac arrest (CA) patients. The aim of this literature review is to investigate the influence of CA combined with TTM on the pharmacokinetics of drugs. Results of preclinical and clinical studies are compared with each other. Only the most important drugs, administered during CA in emergency setting, were studied.

METHODS

A literature search was conducted within PubMed and Google Scholar. The search terms included 'therapeutic hypothermia', 'TTM', 'drug metabolism', 'pharmacokinetics during hypothermia', 'cardiac arrest/etiology'. In Pubmed, MeSH-terms were also included: 'myocardial infarction/therapy', 'heart arrest/complications' and 'hypothermia'. To search for preclinical studies: the search terms 'pigs' and 'swine' were used. After the primary shift of relevant findings, further articles were found through references of these (snowballing method), as well as through related articles as suggested by the databases.

RESULTS

Due to the reduced cardiac output during TTM, most of the distribution volume ([Formula: see text]) of drugs included in this literature study is decreased. Only the [Formula: see text] of chlorzoxazone in CA rats and midazolam in non-CA patients are significantly increased during respectively deep and mild hypothermia. The renal, hepatic and biliary clearance of drugs administered during CA/TTM/hypothermia are decreased.

DISCUSSION

The combination of a decreased [Formula: see text] and a decrease in the metabolization/excretion of drugs during CA/TTM result in higher plasma concentrations compared to the plasma concentrations during CA without TTM.

Genetic Insurance Discrimination in Sudden Arrhythmia Death Syndromes

Background—

There is virtually no information assessing the insurability of families affected with Sudden Arrhythmia Death Syndromes (SADS) for the determination of the nonclinical implications of genetic screening. It is important to identify the barriers and challenges faced by families as a result of genetic screening for SADS to enable equitable access to insurance coverage.

Methods and Results—

To explore the insurance coverage experiences of SADS-affected families, we administered a cross-sectional online survey across North America from April 28, 2012 to November 13, 2013. Participants included individuals with a SADS diagnosis and their relatives who have applied for insurance (health, life, travel, and disability) or have existing insurance coverage. Of 202 participants, 92% had a SADS diagnosis (92%) as either a proband (50%) or an affected relative (42%); 8% of participants were unaffected family members of a proband; and genetic confirmation was reported by 73%. Of the 54% of SADS respondents who applied for insurance, 60% were rejected by insurers. The preexisting SADS diagnosis was the major reason reported for rejection (57%). Most respondents (80%) had insurance coverage through a spouse/parent plan at the time of diagnosis; 14% experienced a subsequent negative effect on coverage. Thirty-nine percent of affected SADS respondents reported an increase in insurance premium rates.

Conclusions—

Increased genetic testing has negatively impacted insurability for SADS patients and affected family members. The challenges in obtaining life and health insurance are mainly because of the preexisting condition, even in the presence of protective laws in the United States.

Clinical Presentation of Pediatric Patients at Risk for Sudden Cardiac Arrest

OBJECTIVES

To identify the clinical presentation of children and adolescents affected by 1 of 4 cardiac conditions predisposing to sudden cardiac arrest: hypertrophic cardiomyopathy, long QT syndrome (LQTS), catecholaminergic polymorphic ventricular tachycardia (CPVT), and anomalous origin of the left coronary artery from the right sinus of Valsalva (ALCA-R).

STUDY DESIGN

This was a retrospective review of newly diagnosed pediatric patients with hypertrophic cardiomyopathy, LQTS, CPVT, and ALCA-R referred for cardiac evaluation at 6 US centers from 2008 to 2014.

RESULTS

A total of 450 patients (257 male/193 female; median age 10.1 years [3.6-13.8 years, 25th-75th percentiles]) were enrolled. Patient age was ≤13 years for 70.4% of the cohort (n = 317). Sudden cardiac arrest was the initial presentation in 7%; others were referred on the basis of abnormal or suspicious family history, personal symptoms, or physical findings. Patients with LQTS and hypertrophic cardiomyopathy were referred most commonly because of family history concerns. ALCA-R was most likely to have abnormal signs or symptoms (eg, exercise chest pain, syncope, or sudden cardiac arrest). Patients with CPVT had a high incidence of syncope and the greatest incidence of sudden cardiac arrest (45%); 77% exhibited exercise syncope or sudden cardiac arrest. This study demonstrated that suspicious or known family history plays a role in identification of many patients ultimately affected by 1 of the 3 genetic disorders (hypertrophic cardiomyopathy, LQTS, CPVT).

CONCLUSION

Important patient and family history and physical examination findings may allow medical providers to identify many pediatric patients affected by 4 cardiac disorders predisposing to sudden cardiac arrest.

Sudden Cardiac Arrest in Pediatrics

Sudden cardiac arrest (SCA) in the pediatric population is a rare and potentially devastating occurrence. An understanding of the differential diagnosis for the etiology of the cardiac arrest allows for the most effective emergency care and provides the patient with the best possible outcome. Pediatric SCA can occur with or without prodromal symptoms and may occur during exercise or rest. The most common cause is arrhythmia secondary to an underlying channelopathy, cardiomyopathy, or myocarditis. After stabilization, evaluation should include electrocardiogram, chest radiograph, and echocardiogram. Management should focus on decreasing the potential for recurring arrhythmia, maintaining cardiac preload, and thoughtful medication use to prevent exacerbation of the underlying condition. The purpose of this review was to provide the emergency physician with a concise and current review of the incidence, differential diagnosis, and management of pediatric patients presenting with SCA.

Utility and limitations of exome sequencing as a genetic diagnostic tool for conditions associated with pediatric sudden cardiac arrest/sudden cardiac death

Background

Conditions associated with sudden cardiac arrest/death (SCA/D) in youth often have a genetic etiology. While SCA/D is uncommon, a pro-active family screening approach may identify these inherited structural and electrical abnormalities prior to symptomatic events and allow appropriate surveillance and treatment. This study investigated the diagnostic utility of exome sequencing (ES) by evaluating the capture and coverage of genes related to SCA/D.

Methods

Samples from 102 individuals (13 with known molecular etiologies for SCA/D, 30 individuals without known molecular etiologies for SCA/D and 59 with other conditions) were analyzed following exome capture and sequencing at an average read depth of 100X. Reads were mapped to human genome GRCh37 using Novoalign, and post-processing and analysis was done using Picard and GATK. A total of 103 genes (2,190 exons) related to SCA/D were used as a primary filter. An additional 100 random variants within the targeted genes associated with SCA/D were also selected and evaluated for depth of sequencing and coverage. Although the primary objective was to evaluate the adequacy of depth of sequencing and coverage of targeted SCA/D genes and not for primary diagnosis, all patients who had SCA/D (known or unknown molecular etiologies) were evaluated with the project’s variant analysis pipeline to determine if the molecular etiologies could be successfully identified.

Results

The majority of exons (97.6 %) were captured and fully covered on average at minimum of 20x sequencing depth. The proportion of unique genomic positions reported within poorly covered exons remained small (4 %). Exonic regions with less coverage reflect the need to enrich these areas to improve coverage. Despite limitations in coverage, we identified 100 % of cases with a prior known molecular etiology for SCA/D, and analysis of an additional 30 individuals with SCA/D but no known molecular etiology revealed a diagnostic answer in 5/30 (17 %). We also demonstrated 95 % of 100 randomly selected reported variants within our targeted genes would have been picked up on ES based on our coverage analysis.

Conclusions

ES is a helpful clinical diagnostic tool for SCA/D given its potential to successfully identify a molecular diagnosis, but clinicians should be aware of limitations of available platforms from technical and diagnostic perspectives.

Electronic supplementary material

The online version of this article (doi:10.1186/s40246-015-0038-y) contains supplementary material, which is available to authorized users.

The Impact of Sports Cardiology on the Practice of Primary Care Sports Medicine: Where Were We, Where Are We, Where Are We Headed?

This article is a commentary on the role of sports cardiologists in the athletic arena and the beneficial impact they offer sports medicine in the comprehensive care of competitive athletes. The focus is a dialogue on current recommendations for primary prevention of sudden cardiac arrest (SCA), incorporating elements of the preparticipation evaluation and continuing care of athletes with diagnosed heart disease (HD). The feasibility and potential advantages of implementing well-designed preparticipation cardiovascular screening programs and the role of sports cardiologists to educate primary care team physicians on secondary prevention of SCA and proper treatment of underlying HD are discussed.

Best practices for ECG screening in children

Screening for conditions associated with sudden cardiac arrest in the United States (US) is aimed at high school athletes in most states and utilizes a preparticipation history and physical form that is not standardized across the US. In Italy, data have shown that their incidence of sudden cardiac arrest has decreased significantly after implementation of an electrocardiographic-based screening program including history and physical exam. The American Heart Association recommendations do not include an electrocardiogram. A recent AHA statement has suggested that those screening athletes should consider all children of similar ages in the selected venue, but still should not include an electrocardiogram. A number of models of screening are presented along with a best practice recommendation for further evaluation and study.

Sudden cardiac death in the young: the bogeyman

Sudden cardiac death in the young is a relatively uncommon but marked event usually related to congenital diseases or anomalies. Despite the prevalence of each condition being variable, most common causes include primary myocardial diseases and arrhythmic disorder, frequently with inheritance pattern. Sudden cardiac death is usually preceded by symptoms, thus making personal and family history fundamental for its prevention. Nevertheless, in more than 50% of cases, sudden cardiac death is the first manifestation of the disease. In this review, we describe the different causes of sudden cardiac death, their incidence, and currently used preventive strategies.

The Electrocardiogram Is a Poor Diagnostic Tool to Detect Left Ventricular Hypertrophy in Children: A Comparison with Echocardiographic Assessment of Left Ventricular Mass

OBJECTIVE

The electrocardiogram (ECG) is used to detect left ventricular hypertrophy (LVH) in children and young adults, and it is considered an important screening tool for the most common causes of sudden cardiac arrest in the United States. However, the reliability and accuracy of the ECG in the detection of LVH are poorly understood. This study's objective was to assess the reliability and accuracy of ECG parameters predicting LVH in comparison with echocardiographic two-dimensional left ventricular mass (2D-LVM) assessment.

DESIGN

Two hundred fifty patients met study criteria with complete 2D-LVM measurements, temporally matched ECGs and no confounding structural heart defects. The echocardiographic diagnosis of LVH was made by 2D-LVM z-score > 2. The electrocardiographic diagnosis of LVH was fulfilled if specific Q, R, or S wave voltages exceeded the normal limits for the respective age groups established by the Davignon, Macfarlane and Rijnbeek datasets, or fulfilled the LVH criteria set forth by adult indices (Sokolow-Lyon, Cornell, Gubner, Romhilt-Estes).

RESULTS

None of the ECG parameters showed significant correlation with 2D-LVM z-scores. In the detection of LVH, the most commonly used R in V6 voltages showed the following results: sensitivity 13-29%, specificity 77-96%, positive predictive value (PPV) 29-50%, and negative predictive value (NPV) 77%. The overall accuracy ranged 65-75%. The accuracy of adult indices for LVH ranged from 49% to 78%.

CONCLUSIONS

The ECG's prediction of LVH is unreliable with dismal sensitivity, variable specificity, poor PPV, and barely acceptable NPV. With such overall poor reliability, the use of current ECG standards in screening for LVH warrants reassessment.

Epidemiological characteristics of sudden cardiac arrest in schools

AIMS

The present study aimed to clarify the incidence and outcomes of sudden cardiac arrests in schools and the clinically relevant characteristics of individuals who experienced sudden cardiac arrests.

METHODS AND RESULTS

We obtained data on sudden cardiac arrests that occurred in schools between January 1, 2005 and December 31, 2009 from the database of the Utstein Osaka Project, a population-based observational study on out-of-hospital cardiac arrests in Osaka, Japan. The data were analyzed to show the epidemiological features of sudden cardiac arrests in schools in conjunction with prehospital documentation. In total, 44 cases were registered as sudden cardiac arrests in schools during the study period. Of these, 34 cases had nontraumatic cardiac arrests. Twenty-one cases (62%) had pre-existing cardiac diseases and/or collapsed during physical exercise. Twenty-three cases (68%) presented with ventricular fibrillation or pulseless ventricular tachycardia, with cases of survival 1 month after cardiac arrest and those having favourable neurological outcome (Cerebral Performance Category 1 or 2) being 12 (52%) and 10 (43%), respectively. The incidence of sudden cardiac arrests in students was 0.23 per 100,000 persons per year, ranging from 0.08 in junior high school to 0.64 in high school. The incidence of sudden cardiac arrests in school faculty and staff was 0.51 per 100,000 persons per year, a rate approximately 2 times of that observed in the students.

CONCLUSIONS

Although sudden cardiac arrests in schools is rare, they majorly occurred in individuals with cardiac diseases and/or during physical exercise and presented as ventricular fibrillation or pulseless ventricular tachycardia observed initially as cardiac arrhythmia.

Demographics, bystander CPR, and AED use in out-of-hospital pediatric arrests

BACKGROUND

In 2005 the American Heart Association released guidelines calling for routine use of automated external defibrillators during pediatric out-of-hospital arrest. The goal of this study was to determine if these guidelines are used during resuscitations.

METHODS

We conducted a secondary analysis of prospectively collected data from 29 U.S. cities that participate in the Cardiac Arrest Registry to Enhance Survival (CARES). Patients were included if they were older than 1 year of age and had a documented resuscitation attempt from October 1, 2005 through December 31, 2009 from an arrest presumed to be cardiac in nature. Hierarchical multivariable logistic regression analysis was used to estimate the associations between age, demographic factors, and AED use.

RESULTS

129 patients were 1-8 years of age (younger children), 88 patients were 9-17 years of age (older children), and 19,338 patients were ≥18 years of age (adults). When compared to adults, younger children were less likely to be found in a shockable rhythm (young children 11.6%, adults 23.7%) and were less likely to have an AED used (young children 16.3%, adults 28.3%). Older children had a similar prevalence of shockable rhythms as adults (31.8%) and AED use (20.5%). A multivariable analysis demonstrated that, when compared to adults, younger children had decreased odds of having an AED used (OR 0.42, 95% CI 0.26-0.69), but there was no difference in AED use among older children and adults.

CONCLUSIONS

Young children suffering from presumed out-of-hospital cardiac arrests are less likely to have a shockable rhythm when compared to adults, and are less likely to have an AED used during resuscitation.

Sports participation during teenage years

Ensuring the safety of young athletes is a priority among health care providers. Controversy remains as to the best method of preparticipation screening. The American Academy of Pediatrics and the American Heart Association currently recommend screening with history and physical examination, without routine electrocardiogram or echocardiography. Meticulous conduction of a cardiac focused history and exam during the preparticipation evaluation can help identify those who may be at risk for sudden cardiac arrest. Understanding presenting signs of the most common cardiac diseases is useful in recognizing those in need of a directed cardiac evaluation before sports participation.

Sudden cardiac death in children (1-18 years): symptoms and causes of death in a nationwide setting

AIMS

Hitherto, sudden cardiac death in children (SCDc)-defined as sudden cardiac death (SCD) in the 1-18 years old-has been incompletely described in the general population. Knowledge on incidence rates, causes of death and symptoms prior to death is sparse and has been affected by reporting and referral bias.

METHODS AND RESULTS

In a nationwide setting all deaths in children aged 1-18 years in Denmark in 2000-06 were included. To chart causes of death and incidence rates, death certificates and autopsy reports were collected and read. By additional use of the extensive healthcare registries in Denmark, we were also able to investigate prior disease and symptoms. During the 7-year study period there was an average of 1.11 million persons aged 1-18 years. There were a total of 1504 deaths (214 deaths per year) from 7.78 million person-years. A total of 114 (7.5%) were sudden and unexpected. A cardiac disease was known prior to death in 18% of all sudden unexpected death cases. In two-thirds of all sudden unexpected death cases no previous medical history was registered. Causes of death in autopsied cases were cardiac or unknown in 70%. Unexplained deaths, presumed to be a primary cardiac arrhythmia, accounted for 28% of autopsied sudden unexpected death cases. Autopsy rate was 77%. There were a total of 87 cases of SCDc (5.8% of all deaths). Prodromal symptoms were noted in 26% and antecedent symptoms in 45% of SCDc cases. The most frequent antecedent symptoms were seizures, dyspnoea, and syncope. In total, 61% of SCDc were not known with any prior disease; 23% were known with congenital or other heart disease prior to death. In total, 43 (49%) of all sudden unexpected deaths died of a potential inherited cardiac disease. The incidence rate of sudden unexpected death was 1.5 per 100 000 person-years. The highest possible incidence rate of SCDc was 1.1 per 100 000 person-years.

CONCLUSION

From a nationwide study of all deaths in a 7-year period more than half of all victims of SCDc experienced antecedent and/or prodromal symptoms prior to death. The incidence rate of sudden death and SCDc was 1.5 and 1.1 per 100 000 person-years, respectively. Cardiac symptoms in young persons should warrant clinical work-up and an autopsy should be performed in all cases of sudden unexpected death in which the deceased was not known with congenital heart disease prior to death. This is pivotal, in the subsequent familial cascade screening, to diagnose and treat potential inherited cardiac diseases in family members.

Sudden unexplained cardiac arrest in apparently healthy children: a single-center experience

This study aimed to determine the causes of sudden cardiac arrest (SCA) in apparently healthy children at a single center in the era of primary prevention (screening questionnaire [SQ]) and secondary prevention (automated external defibrillator [AED] and the automated implantable cardioverter defibrillator [AICD]). Any child 0 to 18 years of age without prior known disease, except for attention deficit disorder, who underwent out-of-the hospital cardiopulmonary resuscitation was included in the study as a SCA subject. A retrospective chart review was used to evaluate the efficacy of the SQ, electrocardiogram (ECG), chest roentgenogram (CXR), and echocardiogram. The findings showed that for 44 of 6,656 children admitted to intensive care with SCA, an AED was used for 39%, an AICD was placed in 18%,and survival to hospital discharge was 50%. The etiology for SCA was identified in 57% of the cases, mostly in those older than 1 year, and the majority of these had a cardiac etiology (50%), whereas 7% had rupture of an arteriovenous malformation. Stimulant medication use was seen in 11% of the SCA subjects. In the best-case scenario of hypothesized primary prevention, a prior SQ, CXR, ECG, or echocardiogram may have detected respectively 18, 9, 23 and 16% of the at-risk cases, and 32% of the cases may have been detected with ECG and SQ together. Based on a historical control cohort, a positive ECG was significantly higher in the children with SCA (p = 0.014). An ECG together with a screening SQ may be more effective in identifying children potentially at risk for SCA than an SQ alone.

The school nurse role in preparing for sudden cardiac arrest in the school setting

Automated external defibrillators (AEDs) were introduced for first responders in 1992 to manage adult cardiac arrest and are now common in many public places. Today AEDs are capable of shocking children under 8 years of age, or less than 55 pounds. This presents a challenge for school nurses, particularly as the prevalence of chronic medical conditions of school children continues to increase. Preparing for a cardiac emergency for a person of any age is stressful and requires a coordinated approach to best manage sudden cardiac arrest (SCA). The school nurse's responsibility is to assess the school setting and the need for an AED, and when indicated, determine the best AED guidelines in schools that accommodate people of all ages.