Sudden Cardiac Death in the Athlete: Bridging the Gaps Between Evidence, Policy, and Practice

Coronary artery calcium and sudden cardiac death: current evidence and future directions

PURPOSE OF REVIEW

To provide a summary of the current evidence and highlight future directions regarding coronary artery calcium (CAC) and risk of sudden cardiac death (SCD).

RECENT FINDINGS

Although up to 80% of all SCD is attributed to coronary heart disease (CHD), the subclinical atherosclerosis markers that help to improve SCD risk prediction are largely unknown. Recent observational data have demonstrated that, after adjustment for traditional risk factors, there is a stepwise higher risk for SCD across increasing CAC burden such that asymptomatic patients without overt atherosclerotic cardiovascular disease (ASCVD) experience a three-fold to five-fold higher SCD risk beginning at CAC at least 100 when compared with CAC = 0. Although the mechanisms underlying increasing CAC and SCD risk have yet to be fully elucidated, risk for myocardial infarction and scar, and/or exercise-induced ischemia may be potential mediators.

SUMMARY

High CAC burden is an important risk factor for SCD in asymptomatic middle-aged adults, suggesting that SCD risk stratification can begin in the early stages of CHD via measurement of calcific plaque on noncontrast computed tomography. Despite the clinical inertia for downstream functional cardiac testing after detecting high CAC, comprehensive ASCVD prevention strategies should be the primary focus for SCD risk reduction.

Sudden Cardiac Death in Athletes: Facts and Fallacies

The benefits of exercise for cardiovascular and general health are many. However, sudden cardiac death (SCD) may occur in apparently healthy athletes who perform at the highest levels. A diverse spectrum of diseases is implicated in SCD in athletes, and while atherosclerotic coronary artery disease predominates in individuals of >35 years of age, primary cardiomyopathies and ion channelopathies are prevalent in young individuals. Prevention of SCD in athletes relies on the implementation of health policies aimed at the early identification of arrhythmogenic diseases (such as cardiac screening) and successful resuscitation (such as widespread utilization of automatic external defibrillators and training members of the public on cardiopulmonary resuscitation). This review will focus on the epidemiology and aetiologies of SCD in athletes, and examine fallacies in the approach to this controversial field. Furthermore, potential strategies to prevent these tragic events will be discussed, analysing current practice, gaps in knowledge and future directions.

High level physical activity in cardiac rehabilitation: Implications for exercise training and leisure-time pursuits

IMPORTANCE

Regular moderate-to-vigorous physical activity and increased levels of cardiorespiratory fitness (CRF) are widely promoted as cardioprotective measures in secondary prevention interventions.

OBSERVATIONS

A low level of CRF increases the risk of cardiovascular disease (CVD) to a greater extent than merely being physically inactive. An exercise capacity <5 metabolic equivalents (METs), generally corresponding to the bottom 20% of the fitness continuum, indicates a higher mortality group. Accordingly, a key objective in early cardiac rehabilitation (CR) is to increase the intensity of training to >3 METs, to empower patients to vacate this "high risk" group. Moreover, a "good" exercise capacity, expressed as peak METs, identifies individuals with a favorable long-term prognosis, regardless of the underlying extent of coronary disease. On the other hand, vigorous-to-high intensity physical activity, particularly when unaccustomed, and some competitive sports are associated with a greater incidence of acute cardiovascular events. Marathon and triathlon training/competition also have limited applicability and value in CR, are associated with acute cardiac events each year, and do not necessarily provide immunity to the development of or the progression of CVD. Furthermore, extreme endurance exercise regimens are associated with an increased incidence of atrial fibrillation and accelerated coronary artery calcification.

CONCLUSIONS AND RELEVANCE

High-intensity training offers a time-saving alternative to moderate intensity continuous training, as well as other potential advantages. Additional long-term studies assessing safety, adherence, and morbidity and mortality are required before high-intensity CR training can be more widely recommended, especially in previously sedentary patients with known or suspected CVD exercising in non-medically supervised settings.

Electrocardiographic and Echocardiographic Findings in Elite Ghanaian Male Soccer Players

OBJECTIVE

To analyze the athlete's heart of adult and adolescent elite male soccer players by electrocardiography (ECG) and echocardiography (ECHO) and to describe typical ECG and ECHO findings in this cohort (West African elite soccer players).

DESIGN

A cross-sectional study of ECGs and ECHOs conducted as part of precompetition medical assessment for national male soccer teams preparing for various Fédération Internationale de Football Association (FIFA) tournaments in 2016 and 2017.

SETTING

Ghana National Football Association.

PARTICIPANTS

One hundred fifty-nine players playing for the National male soccer teams preparing for tournaments in 2016 and 2017.

INTERVENTIONS

Precompetition medical assessment using ECGs and ECHOs.

MAIN OUTCOME MEASURES

Number of athletes with abnormal ECGs and ECHO findings.

RESULTS

Twenty-three percent of the players had abnormal ECGs. Nine percent of the participants had T-wave inversions in lateral leads (V5-V6). Sokolow-Lyon criteria for left ventricular hypertrophy were present in 64% of participants. Thirty-six (23%) players had left ventricular wall thickness (LVWT) ≥13 mm, with no player exceeding 16 mm. Four percent of players had left ventricular cavity dimension greater than 60 mm. Relative wall thickness >0.42 was present in 44% of the players.

CONCLUSIONS

Uncommon ECG changes seem to be more common in elite Ghanaian soccer players compared with previously reported results for Caucasians and even mixed populations of black athletes. Although ST elevation, T-wave inversions, and LVWT up to 15 mm are common, ST depression, deep T-waves in lateral leads, and LVWT ≥16 mm always warrant further clinical and scientific investigations.

Chronic Stress, Exercise and Cardiovascular Disease: Placing the Benefits and Risks of Physical Activity into Perspective

Chronic stress, which has been exacerbated worldwide by the lingering COVID pandemic, has been strongly linked to cardiovascular disease (CVD). In addition, autonomic dysregulation via sustained sympathetic activity has been shown to increase the risk of arrhythmias, platelet aggregation, acute coronary syndromes and heart failure. Fortunately, effective coping strategies have been shown to attenuate the magnitude of hyperarousal associated with the stress response, including moderate-to-vigorous lifestyle activity and/or structured exercise. A good-to-excellent level of cardiorespiratory fitness also appears to be highly cardioprotective. These beneficial effects have been substantiated by numerous studies that have evaluated the levels of stress reactivity and stress recovery in physically active individuals versus matched sedentary controls, as well as before and after exercise interventions. On the other hand, unaccustomed strenuous exercise in habitually sedentary persons with underlying CVD is associated with a disproportionate incidence of acute cardiac events. Moreover, extreme exercise regimens appear to increase coronary calcification and the likelihood of developing atrial fibrillation. This review summarizes these relations and more, with specific reference to placing the benefits and risks of physical activity into perspective.

Causes of sudden cardiac death in young athletes and non-athletes: systematic review and meta-analysis: Sudden cardiac death in the young

INTRODUCTION

The etiology of sudden cardiac death (SCD) in young people continues to attract much attention. This meta-analysis aimed to identify the most frequent causes of SCD in individuals aged ≤35 years, the differences between athletes and non-athletes and geographic areas.

METHODS

Studies published between 01/01/1990 and 01/31/2020 and evaluating post-mortem the aetiology of SCD in young individuals (≤35 years) were included. Individuals were divided into athletes and non-athletes. Studies that did not report separate data between athletes and non-athletes were excluded.

RESULTS

Thirty-four studies met the inclusion criteria, and a total population of 5,060 victims of SCD were analyzed (2,890 athletes, 2,170 non-athletes). Comparing the causes of SCD between athletes and non-athletes, non-ischemic left ventricular scar (NILVS) (5.1% vs. 1.1%, p=0.01) was more frequent in the former, while coronary artery disease (CAD) (19.6% vs. 9.1%, p=0.009), arrhythmogenic cardiomyopathy (ACM) (11.5% vs. 4.7%, p=0.03) and channelopathies (8.4% vs. 1.9%, p=0.02) were more frequent in the latter. In studies published in the last decade, hypertrophic cardiomyopathy (HCM) (p=0.002), dilated cardiomyopathy (p=0.047), and anomalous origin of coronary arteries (AOCA) (p=0.009) were more frequently the causes of SCD in athletes while aortic dissection (0.022) was the cause in non-athletes. HCM (p=0.01) and AOCA (p=0.004) were more frequently the causes of SCD in the US while ACM (p=0.001), structurally normal heart (p=0.02), and channelopathies (p=0.02) were more frequent in Europe.

CONCLUSIONS

Among the causes of SCD, NILVS was the more frequent cause in athletes, while CAD, ACM and channelopathies were more frequent causes in non-athletes. The causes of SCD differ between the US and Europe.

[Cardiac arrest under special circumstances]

These guidelines of the European Resuscitation Council (ERC) Cardiac Arrest under Special Circumstances are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the modifications required for basic and advanced life support for the prevention and treatment of cardiac arrest under special circumstances; in particular, specific causes (hypoxia, trauma, anaphylaxis, sepsis, hypo-/hyperkalaemia and other electrolyte disorders, hypothermia, avalanche, hyperthermia and malignant hyperthermia, pulmonary embolism, coronary thrombosis, cardiac tamponade, tension pneumothorax, toxic agents), specific settings (operating room, cardiac surgery, cardiac catheterization laboratory, dialysis unit, dental clinics, transportation [in-flight, cruise ships], sport, drowning, mass casualty incidents), and specific patient groups (asthma and chronic obstructive pulmonary disease, neurological disease, morbid obesity, pregnancy).

European Resuscitation Council Guidelines 2021: Cardiac arrest in special circumstances

These European Resuscitation Council (ERC) Cardiac Arrest in Special Circumstances guidelines are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the modifications required to basic and advanced life support for the prevention and treatment of cardiac arrest in special circumstances; specifically special causes (hypoxia, trauma, anaphylaxis, sepsis, hypo/hyperkalaemia and other electrolyte disorders, hypothermia, avalanche, hyperthermia and malignant hyperthermia, pulmonary embolism, coronary thrombosis, cardiac tamponade, tension pneumothorax, toxic agents), special settings (operating room, cardiac surgery, catheter laboratory, dialysis unit, dental clinics, transportation (in-flight, cruise ships), sport, drowning, mass casualty incidents), and special patient groups (asthma and COPD, neurological disease, obesity, pregnancy).

Implementing a Standardized Cardiac Protocol for the Adolescent Preparticipation Sports Examination

INTRODUCTION

To evaluate adolescent athletes for cardiovascular (CV) abnormalities before engaging in competitive sports, the American Heart Association guidelines recommend preparticipation screening. The initiative aimed to implement a standardized protocol to increase the identification of CV abnormalities during athletic physical examinations.

METHOD

A rapid-cycle model with four Plan-Do-Study-Act cycles was implemented in two urgent care clinics. Providers used a CV-specific screening checklist; parents were engaged in a discussion about the importance of this screening, and team engagement activities were used. Outcomes were measured with chart audits and surveys.

RESULTS

Because of the intervention, 62% of athletes were screened, with 29% identified as having a CV risk. The satisfaction of the patients and the team increased by 3% and 62.5%, respectively.

DISCUSSION

Despite competing foci in the clinics, athletes were properly screened using a standardized checklist, which is easily sustainable and can be duplicated in other settings.

Mortality of Japanese Olympic athletes in 1964 Tokyo Olympic Games

Objectives

To compare the mortality of Japanese athletes in the 1964 Tokyo Olympic Games with that of the Japanese population, and to elucidate factors associated with their mortality.

Methods

We obtained from the Japan Sport Association study subjects’ biographical information, information on lifestyles and medical data. Missing data were obtained from online databases. Standardised mortality ratio (SMR) was calculated to compare athletes’ mortality with the Japanese population. Cox proportional hazards model was applied to estimate the HR for each category of body mass index (BMI), smoking history and handgrip strength. This analysis was limited to male athletes due to the small number of female athletes.

Results

Among 342 (283 men, 59 women) athletes, deaths were confirmed for 70 (64 men, 6 women) athletes between September 1964 and December 2017. Total person years was 15 974.8, and the SMR was 0.64 (95% CI 0.50 to 0.81). Multivariate analysis performed on 181 male athletes. Mortality was significantly higher for BMI≥25 kg/m² than for 21–23 kg/m² (HR: 3.03, 95% CI 1.01 to 9.07). We found no statistically significant associations between smoking history and mortality; the HR (95% CI) for occasional and daily smokers were 0.82 (0.26 to 2.57) and 1.30 (0.55 to 3.03) compared with never smokers. We also found no statistically significant associations between handgrip strength and mortality (P for trend: 0.51).

Conclusion

Japanese athletes in the 1964 Tokyo Olympic Games lived longer than the Japanese population. BMI≥25 kg/m² was associated with higher mortality, but smoking history and handgrip strength were not associated with mortality.

FIFA Sudden Death Registry (FIFA-SDR): a prospective, observational study of sudden death in worldwide football from 2014 to 2018

OBJECTIVE

To investigate the underlying causes and regional patterns of sudden death in football (soccer) players worldwide to inform and improve existing screening and prevention measures.

METHODS

From 2014 to 2018 cases of sudden cardiac death (SCD), survived sudden cardiac arrest (SCA) and traumatic sudden death were recorded by media monitoring (Meltwater), a confidential web-based data platform and data synchronisation with existing national Sudden Death Registries (n=16). Inclusion criteria were met when sudden death occurred during football-specific activity or up to 1 hour afterwards. Death during other activities was excluded.

RESULTS

A total of 617 players (mean age 34±16 years, 96% men) with sudden death were reported from 67 countries; 142 players (23%) survived. A diagnosis by autopsy or definite medical reports was established in 211 cases (34%). The leading cause in players >35 years was coronary artery disease (76%) and in players ≤35 years was sudden unexplained death (SUD, 22%). In players ≤35 years the leading cause of SCD varied by region: cardiomyopathy in South America (42%), coronary artery anomaly in North America (33%) and SUD in Europe (26%). Traumatic sudden death including commotio cordis occurred infrequently (6%). Cardiopulmonary resuscitation (CPR) resulted in a survival rate of 85% with the use of an automated external defibrillator (AED) compared with 35% without.

CONCLUSIONS

Regional variation in SCD aetiology should be verified by expansion of national registries and uniform autopsy protocols. Immediate access to an AED at training and competition sites, as well as CPR training for players, coaches and staff members, is needed to improve survival from SCA.

Dietary Thiols: A Potential Supporting Strategy against Oxidative Stress in Heart Failure and Muscular Damage during Sports Activity

Moderate exercise combined with proper nutrition are considered protective factors against cardiovascular disease and musculoskeletal disorders. However, physical activity is known not only to have positive effects. In fact, the achievement of a good performance requires a very high oxygen consumption, which leads to the formation of oxygen free radicals, responsible for premature cell aging and diseases such as heart failure and muscle injury. In this scenario, a primary role is played by antioxidants, in particular by natural antioxidants that can be taken through the diet. Natural antioxidants are molecules capable of counteracting oxygen free radicals without causing cellular cytotoxicity. In recent years, therefore, research has conducted numerous studies on the identification of natural micronutrients, in order to prevent or mitigate oxidative stress induced by physical activity by helping to support conventional drug therapies against heart failure and muscle damage. The aim of this review is to have an overview of how controlled physical activity and a diet rich in antioxidants can represent a “natural cure” to prevent imbalances caused by free oxygen radicals in diseases such as heart failure and muscle damage. In particular, we will focus on sulfur-containing compounds that have the ability to protect the body from oxidative stress. We will mainly focus on six natural antioxidants: glutathione, taurine, lipoic acid, sulforaphane, garlic and methylsulfonylmethane.

Exercise-Related Acute Cardiovascular Events and Potential Deleterious Adaptations Following Long-Term Exercise Training: Placing the Risks Into Perspective-An Update: A Scientific Statement From the American Heart Association

Epidemiological and biological plausibility studies support a cause-and-effect relationship between increased levels of physical activity or cardiorespiratory fitness and reduced coronary heart disease events. These data, plus the well-documented anti-aging effects of exercise, have likely contributed to the escalating numbers of adults who have embraced the notion that "more exercise is better." As a result, worldwide participation in endurance training, competitive long distance endurance events, and high-intensity interval training has increased markedly since the previous American Heart Association statement on exercise risk. On the other hand, vigorous physical activity, particularly when performed by unfit individuals, can acutely increase the risk of sudden cardiac death and acute myocardial infarction in susceptible people. Recent studies have also shown that large exercise volumes and vigorous intensities are both associated with potential cardiac maladaptations, including accelerated coronary artery calcification, exercise-induced cardiac biomarker release, myocardial fibrosis, and atrial fibrillation. The relationship between these maladaptive responses and physical activity often forms a U- or reverse J-shaped dose-response curve. This scientific statement discusses the cardiovascular and health implications for moderate to vigorous physical activity, as well as high-volume, high-intensity exercise regimens, based on current understanding of the associated risks and benefits. The goal is to provide healthcare professionals with updated information to advise patients on appropriate preparticipation screening and the benefits and risks of physical activity or physical exertion in varied environments and during competitive events.

"It Doesn't Make Sense for Us Not to Have One"-Understanding Reasons Why Community Sports Organizations Chose to Participate in a Funded Automated External Defibrillator Program

OBJECTIVE

Implementation of automated external defibrillators (AEDs) in community sports settings is an important component of emergency medical planning. This study aimed to understand motivations for why sports organizations participated in a government-funded program that provided AEDs and associated first-aid training.

DESIGN

Face-to-face interviews.

SETTING

Community sports organizations in Victoria, Australia.

PARTICIPANTS

Representatives from 14 organizations who participated in a government-funded AED program.

MAIN OUTCOME MEASURES

Motivations to participate in the AED program were explored using a qualitative descriptive approach.

RESULTS

Two overarching themes emerged: awareness of the program and decision to apply. Awareness was gained indirectly through grant advertising in newsletters/emails/web sites and directly through their sporting associations. For most organizations, there was no decision process per se, rather, the opportunity to apply was the key determinant for participating in the program. A duty of care also emerged as a key driving factor, with recognition of AEDs as a valuable asset to communities broadly, not just the participants' immediate sports setting. Reflecting on participation in the program, these participants identified that it was important to increase awareness about AED ownership and use. The program benefits were clearly summed up as being best prepared for a worst-case scenario.

DISCUSSION

This study provides new understanding of why community sports organizations apply for an AED and training. The strongest reason was simply the opportunity to acquire this at no cost. Therefore, for wider implementation of AEDs, additional funding opportunities, targeted awareness of these opportunities, and continued promotion of AED importance are recommended.

Continuous electrocardiogram changes preceding phenotypic expression for 8 years in an athlete with hypertrophic cardiomyopathy: a case report

Background

Hypertrophic cardiomyopathy is one of the most common causes of sudden cardiac death in young athletes. Performing, comparing, and monitoring serial electrocardiograms over time can help to detect potential cardiovascular diseases and to prevent malignant cardiac events in these populations.

Case presentation

A young Han Chinese male football player had abnormal electrocardiograms for 8 years without any subjective discomfort. Electrocardiograms revealed that T-wave inversions increased from 1 mm to a maximum of 5 mm on lead I and fluctuated around 5 mm on lead avL. Q-wave duration ranged from 40 ms to 60 ms, its depth increased to a maximum of 8 mm and was much greater than 40% of the R waves in depth in II, III, and avF leads. Echocardiography showed increasingly thickened interventricular septum from 10 mm to 13 mm, enlarged left atrium and ventricle, and reduced left ventricular ejection fraction. Coronary angiography showed no distinct stenosis. Emission computed tomography revealed mild myocardial ischemia of the left ventricular inferior wall. These unusual electrocardiogram manifestations were initially regarded as benign alterations of a highly trained athlete. Upon reviewing the clinical information and the newest criteria for electrocardiographic interpretation in athletes, hypertrophic cardiomyopathy was identified. The misreading of electrocardiograms is not uncommon, thus predisposing such patients to high susceptibility to exercise-induced sudden cardiac death.

Conclusions

We propose that abnormal electrocardiogram findings reveal the initial expression of underlying cardiac diseases such as hypertrophic cardiomyopathy, preceding the symptoms and signs by many years. Accordingly, early detection and continuous surveillance are important for athletes with such electrocardiogram patterns, and improvement of physicians’ expertise is crucial.

Integration of 12-Lead Electrocardiograms Into Preparticipation Screenings to Prevent Sudden Cardiac Death in High School Athletes

INTRODUCTION

Sudden cardiac arrest continues to be the leading cause of death in young athletes despite preparticipation sports screening (PPS). The devastating loss of children to sudden cardiac arrest has led communities to demand more comprehensive heart screenings. The purpose of this study was to evaluate a community youth heart screening program in Minnesota.

METHOD

A retrospective chart review of 840 participants aged 14 to 18 years from August 2015 through March 2017 was conducted.

RESULTS

Referrals were made for two abnormal electrocardiography results, 12 abnormal echocardiography results, and 59 elevated blood pressure readings. Cross-tabulations showed one participant with an abnormal electrocardiogram and six participants with abnormal echocardiograms who had no other abnormal findings at the screening. Findings were not statistically significant.

DISCUSSION

It was clinically significant that six participants were found to have potentially lethal electrical or structural heart abnormalities who would have otherwise have remained unidentified with the standard preparticipation sports screening guidelines.

Preparticipation Cardiovascular Screening of Student-Athletes with Echocardiography: Ethical, Clinical, Economic, and Legal Considerations

PURPOSE OF REVIEW

To identify whether the use of echocardiography is a viable approach for the screening of athletes for the prevention of sudden cardiac death when considering ethical, clinical, economic, and legal issues.

RECENT FINDINGS

Ethical musings, echocardiographic findings, economic calculations, and legal analysis suggest that echocardiographic screening may reduce sudden cardiac death on the athletic field. Ethical, clinical, economic, and legal considerations suggest echocardiographic screening is a viable option to meet the societal goal to prevent athletic field sudden death.

School Nurses' Perceived Barriers and Perceptual Influences When Implementing AED Programs

School nurses' experienced barriers and benefits with perceptions of self-efficacy are important factors to consider for program implementation in the school setting. Little research has been done in the area of automated external defibrillator (AED) program implementation by the school nurse for the treatment of sudden cardiac arrest. The purpose of this study was to identify benefits of and barriers to AED program implementation in public schools and measure school nurses' self-efficacy related to their role as a change agent in program implementation. Results revealed that school nurses are functioning with a high level of self-efficacy in their ability to influence major health-care decisions in the school setting, and despite barriers, AED program implementation is considered beneficial and a necessary component of emergency care.

Sudden cardiac death in athletes and the value of cardiovascular magnetic resonance

Sudden cardiac death (SCD) is the nontraumatic death, due to loss of heart function that occurs suddenly and unexpectedly within 6 hours of a previously normal state of health. It is related to intense competitive sports promoting ventricular tachycardia (VT)/ventricular fibrillation (VF) in the presence of underlying abnormal substrate. A serial evaluation of cardiac physiologic changes taking place during training will allow the better understanding of athlete's heart and will facilitate its discrimination from other grey-zone cardiomyopathies. According to the ESC recommendations, a pre-participation evaluation should include medical history, physical examination as well as a 12-lead electrocardiogram (ECG). Additional tests, such as echocardiography, 24-hours Holter monitoring, stress testing and cardiovascular magnetic resonance (CMR) should be requested upon positive findings at the initial evaluation. Cardiovascular magnetic resonance can be of great value in the differential diagnosis between various cardiomyopathies including hypertrophic cardiomyopathy (HCM), arrhythmogenic right ventricular cardiomyopathy (ARVC), left ventricle noncompaction cardiomyopathy (LVNC) and athlete's heart. This is due to its great versatility that can provide reliable and reproducible anatomical, functional and tissue characterization information, which are operator and acoustic window independent.

The pre-participation screening in young athletes: which protocol do we need exactly?

The aim was to assess the utility and feasibility of a comprehensive cardiac screening protocol in young athletes before participation in sports. A total of 380 athletes referring before participation in sports, between April, 2014 and April, 2015, were included in this study. The mean age was 12.4 years. A screening protocol has been applied to all, including personal and family history, physical examination, 12-lead electrocardiography, transthoracic echocardiography, 24-hour rhythm Holter analysis, and treadmill exercise test. The most frequent complaints were chest pain in 19 (5%), dyspnoea in 13 (3.4%), and dizziness and fainting in five patients (1.3%) on exercise. There was sudden death and arrhythmia in 41 patients (10.7%) owing to family history. Heart murmur was present in 20 (5.2%) and hypertension in 10 patients (2.6%) on physical examination. The 12-lead electrocardiography was abnormal in 9 patients (2.4%). The findings of transthoracic echocardiography were insignificant in 47 patients (12.3%) and in five patients (1.3%) a haemodynamically important condition was detected. The 24-hour rhythm Holter analysis was abnormal in six patients (1.5%). There were significant ST changes in two patients (0.5%) on treadmill exercise test with normal findings on myocardial perfusion scans. No significant relation was present between findings of screening protocol and transthoracic echocardiography, 24-hour rhythm Holter analysis, or treadmill exercise test results. Pre-participation screening in young athletes should consist of a targeted personal history, family history, physical examination, and 12-lead electrocardiography. Other tests should be applied only if the screening indicates the presence of a cardiovascular disease.

Early recognition of sudden cardiac arrest in athletes during sports activity

INTRODUCTION

Sudden cardiac arrest (SCA) in athletes is an unexpected life-threatening event, which is often not recognised early and cardiopulmonary resuscitation (CPR) is not always initiated immediately. We describe key features to rapidly recognise non-traumatic SCA in athletes during sports activity.

METHODS

We reviewed videos and images of athletes suffering from non-traumatic SCA during sports activity. We searched Google images, Google videos and YouTube.com using the keywords 'sudden cardiac death athlete' and 'resuscitation athlete'. We analysed (1) the athlete's performance before syncope, (2) the athlete's performance at the start of syncope, (3) the position of the body, and (4) the athlete's facial expressions before CPR. We analysed our data by describing these four features to answer our research question.

RESULTS

We analysed the sequence of events in six well-known soccer players in whom a camera-witnessed non-traumatic SCA occurred during their athletic activity. All six athletes showed no changes before syncope. Four became unstable while standing and unexpectedly collapsed falling on their back. Two suddenly 'dropped dead' and fell face down. All six had their eyes wide open with a fixed gaze and fixed pupils.

CONCLUSIONS

Sudden unexpected loss of consciousness in an athlete in action and a fixed gaze eye position are key features of SCA. Immediate cardiac massage should follow. The described features to immediately recognise SCA in athletes during sports activity should be taught to everyone involved in athletic activity leading to earlier recognition of SCA followed by earlier CPR.

Prevention of sudden cardiac death in athletes, sportspersons and marathoners in India

The annual incidence of sudden cardiac death (SCD) in athletes is significantly lower than the general population. However, when SCD occurs in an athlete during sporting event or training, it sends shockwaves in the society and raises questions about cardiovascular effects of sports and exercise. This document reviews the causes and mechanism of SCD in sports and exercise in young and older athletes. In the Indian context, we suggest a ‘pre-participation screening’ of young and older athletes and consider a ‘supervised, graded exercise regime’ for the uninitiated, older sports participant. Finally, the document proposes medical infrastructure required to successfully revive a victim of sudden cardiac arrest during a sporting event.

CARDIOVASCULAR SCREENING OF YOUNG ATHLETES: A REVIEW OF ECONOMIC EVALUATIONS

Objectives: Some experts have promoted preparticipative cardiovascular screening programs for young athletes and have claimed that such programs were cost-effective without performing a critical analysis of studies supporting this statement. In this systematic review, a critical assessment of economic evaluations on these programs is performed to determine if they really provide value for money.

Methods: A systematic review of economic evaluations was performed on December 24, 2014. Web sites of health technology assessment agencies, the Cochrane database of systematic review, the National Health Service Economic Evaluation Database of the Cochrane Library, EMBASE, Medline, Psychinfo, and EconLit were searched to retrieve (reviews of) economic evaluations. No language or time restrictions were imposed and predefined selection criteria were used. Selected studies were critically assessed applying a structured data extraction sheet.

Results: Five relevant economic evaluations were critically assessed. Results of these studies were mixed. However, those in favor of screening made (methodological) incorrect choices, of which the most important one was not taking into account a no-screening alternative as comparator. Compared with no screening, other strategies (history and physical examination or history and physical examination plus electrocardiogram) were not considered cost-effective.

Conclusions: Results of primary economic evaluations should not be blindly copied without critical assessment. Economic evaluations in this field lack the support of robust evidence. Negative consequences of screening (false positive findings, overtreatment) should also be taken into account and may cause more harm than good. A mass screening of young athletes for cardiovascular diseases does not provide value for money and should be discouraged.

Death in Community Australian Football: A Ten Year National Insurance Claims Report

While deaths are thought to be rare in community Australian sport, there is no systematic reporting so the frequency and leading causes of death is unknown. The aim of this study was to describe the frequency and cause of deaths associated with community-level Australian Football (AF), based on insurance-claims records. Retrospective review of prospectively collected insurance-claims for death in relation to community-level AF activities Australia-wide from 2004 to 2013. Eligible participants were aged 15+ years, involved in an Australian football club as players, coaches, umpires or supporting roles. Details were extracted for: year of death, level of play, age, sex, anatomical location of injury, and a descriptive narrative of the event. Descriptive data are presented for frequency of cases by subgroups. From 26,749 insurance-claims relating to AF, 31 cases were in relation to a death. All fatalities were in males. The initial event occurred during on-field activities of players (football matches or training) in 16 cases. The remainder occurred to people outside of on-field football activity (n = 8), or non-players (n = 7). Road trauma (n = 8) and cardiac conditions (n = 7) were the leading identifiable causes, with unconfirmed and other causes (including collapsed or not yet determined) comprising 16 cases. Although rare, fatalities do occur in community AF to both players and people in supporting roles, averaging 3 per year in this setting alone. A systematic, comprehensive approach to data collection is urgently required to better understand the risk and causes of death in participants of AF and other sports.

Prevalence of Cardiovascular Disorders Among Iranian Elite Athletes

BACKGROUND

Athletes' health is an important issue and for promoting it, pre-participation examination (PPE) is widely performed by responsible bodies around the world.

OBJECTIVES

This study was to determine prevalence of cardiovascular disorders among athletes participating in the Asian games and answering the question whether the electrocardiogram (ECG) is a necessary part of pre-participation examination (PPE) for prevention of sudden cardiac death.

MATERIALS AND METHODS

All athletes participated at Asian games came to sports medicine federation for a PPE including a comprehensive questionnaire, physical examination and ECG. In this retrospective study all profiles of 338 athletes have been studied as well as their electrocardiograms. Multiple logistic regressions as well as Firth's bias reduction were used with R statistical software and SPSS. For predicting the changes in ECG, receiver operating characteristic (ROC) curve has done.

RESULTS

Among 388 athletes, 80 (20.6%) were female and 308 (79.4%) male with mean age of 23.2 + 8 years. Nine athletes (2.3%) were smokers, 28 of them (7.2%) experienced chest pain and discomfort, 45 of them (13.3%) had palpitations and 28 (7.2%) had history of anemia. Study of their electrocardiograms showed that long Q-T interval was not seen for anyone, but evidence of left ventricular hypertrophy was seen in 12 (3.1%), inverted T wave in 6 (1.5%), and right bundle branch block in 45 (13.3%).

CONCLUSIONS

PPE provides very important information of athletes' health. This study has shown that there was not any significant relation between current examination and electrocardiogram changes but regarding the ECG changes we recommend it as a routine part of PPE.

Hypertrophic Cardiomyopathy as a Cause of Sudden Cardiac Death in the Young: A Meta-Analysis

BACKGROUND

Sudden cardiac death is often linked with hypertrophic cardiomyopathy in young athletes, but with a divergence of study results. We performed a meta-analysis to compare the prevalence of sudden cardiac deaths associated with hypertrophic cardiomyopathy vs sudden cardiac deaths associated with structurally normal hearts.

METHODS

A structured search of MEDLINE was conducted for studies published from 1990 through 2014. Retrospective cohort studies, patient registries, and autopsy series examining sudden cardiac death etiology in young individuals (age ≤35 years) were included. A random-effects model was applied to generate pooled summary estimates of the percentage of sudden cardiac deaths with structurally normal hearts at postmortem vs those caused by hypertrophic cardiomyopathy. Heterogeneity was assessed using I(2). Subgroup analyses were conducted based on study location, patient age groups, and population types.

RESULTS

Thirty-four studies were included, representing a combined sample of 4605 subjects. The overall pooled percentage of sudden cardiac deaths caused by hypertrophic cardiomyopathy was 10.3% (95% confidence interval [CI], 8.0%-12.6%; I(2) = 87.2%), while sudden cardiac deaths with structurally normal hearts at death were more common (P <.001) at 26.7% (95% CI, 21.0%-32.3%; I(2) = 95.3%). In nonathlete subjects, the pooled percentage of sudden cardiac deaths associated with structurally normal hearts (30.7%; 95% CI, 23.0%-38.4%; I(2) = 96.3%) were significantly more common (P <.001) than sudden cardiac death caused by hypertrophic cardiomyopathy (7.8%; 95% CI, 5.8%-9.9%; I(2) = 80.1%). Among athletes, there was no significant difference between summary estimates of hypertrophic cardiomyopathy and structurally normal hearts (P = .57), except in Europe where structurally normal hearts were more common (P = .01).

CONCLUSIONS

Hypertrophic cardiomyopathy is not a more common finding at death than structurally normal hearts in young subjects with sudden cardiac death. Increased attention should be directed toward identifying causes of death associated with a structurally normal heart in subjects with sudden cardiac death.

Benign and pathological electrocardiographic changes in athletes

Sudden cardiac death is the leading cause of death in athletes during sport. It is a tragic event that generates significant media attention and discussion throughout society as to whether everything possible had been done to prevent it. Regular physical exercise causes cardiac remodeling at both the mechanical and electrical level, known as athlete's heart, resulting in an electrocardiogram (ECG) considered abnormal compared with the ECGs of the general population. Some of these electrocardiographic changes are considered normal or physiological in athletes, while others suggest underlying cardiac disease with the potential to cause sudden cardiac death. There is thus an urgent need to define the electrocardiographic patterns that allow or prohibit participation in sports, and to differentiate them in terms of gender, ethnicity and age. The purpose of this review is to present the latest data on the electrocardiographic changes considered benign or pathological that are typically found in athletes and to critically analyze the most recent criteria for classifying ECGs in this population (the Seattle criteria), comparing them with previous guidelines and with the latest studies on the subject. This article also examines the question of including ECGs in pre-participation screening programs, the US and European approaches to the subject, and the most up-to-date data on the sensitivity, specificity and cost-effectiveness of the ECG in athletes.

Electrocardiogram in Preparticipation Athletic Evaluations among Insured Youths

OBJECTIVE

To retrospectively characterize electrocardiogram (ECG) use among preparticipation history and examinations (PPEs).

STUDY DESIGN

Using the 2005 to 2010 MarketScan insurance database, we identified subjects aged 5-21 years with either a PPE with an ECG or a PPE alone, excluding those with known cardiac diagnoses. We described cardiology referrals and subspecialty testing within 180 days and cardiac diagnoses within 1 year of the PPE, and the costs of testing in each group.

RESULTS

From 2005-2009, 503 304 PPEs occurred in 419 456 subjects, of which 8621 (2%) included an ECG. ECG use increased from 12-20 per 1000 PPEs from 2005-2009. Females, lower socioeconomic status, and rural settings were associated with fewer ECGs. Thirteen percent of PPEs with ECG and 0.5% of PPEs alone led to a cardiology referral. After PPEs with ECG, cardiac disease was identified in 18% (2% sports-limiting); after PPEs alone, cardiac disease was identified in 0.5% (0.03% sports-limiting). The PPE had a sensitivity of 44% and a specificity of 98.6% of identifying cardiac disease. The total reimbursement cost of PPEs plus testing was $80 396 464 ($160 per PPE).

CONCLUSIONS

These real-world data demonstrate that community providers selectively use the ECG as part of the PPE with a high rate of identification of cardiac disease. Mass ECG screening would need to be more efficient at identifying disease than this selective approach.

Student athletes, sudden cardiac death, and lifesaving legislation: a review of the literature

PURPOSE

The purpose of this article is to present findings of a literature review examining the use of automatic external defibrillators (AEDs) for student athletes experiencing sudden cardiac arrest and variances in state legislation regarding the mandatory placement of AEDs in school gymnasiums and athletic fields.

METHODS

A broad search of computerized databases was conducted utilizing PubMed, Medline, CINHAHL, and the Cochrane Databases, which provided a broad but not exhaustive review of the current literature related to student athletes, sudden cardiac death, and the use of AEDs. The articles were evaluated and graded using Stetler's strength of evidence guidelines.

FINDINGS

A total of 17 articles are included in this literature review (Stetler's Grade I, n = 1; Grade II, n = 2; Grade III, n =2; Grade IV, n = 5; Grade V, n = 3; and Grade VI, n = 4). The literature produced few meta-analyses of controlled studies, experimental studies, and quasi-experimental studies on the topic of student athletes at risk for sudden cardiac death. The majority of the literature is based on expert opinion, case reports, and retrospective data sets. The literature does support the correlation of early cardiopulmonary resuscitation and defibrillation with increased survival rates among persons experiencing sudden cardiac arrest.

CONCLUSIONS

Additional evidence-based research is needed to support the long-term outcomes of AED legislation and its utility in sparing the lives of student athletes. However, the evidence supporting early intervention, a coordinated emergency plan, and rapid emergency medical services response is conclusive enough to warrant state or federal legislation mandating that AEDs be present in all school gyms and athletic fields.

Life-threatening events during endurance sports: is heat stroke more prevalent than arrhythmic death?

BACKGROUND

Two important causes of sudden death during endurance races are arrhythmic death and heat stroke. However, "arrhythmic death" has caught practically all the attention of the medical community whereas the importance of heat stroke is less appreciated.

OBJECTIVES

The study sought to determine what percentage of life-threatening events during endurance races are due to heat stroke or cardiac causes.

METHODS

This retrospective study examined all the long distance popular races that took place in Tel Aviv from March 2007 to November 2013. The number of athletes at risk was known. The number of athletes developing serious sport-related events and requiring hospitalization was known. Life-threatening events were those requiring mechanical ventilation and hospitalization in intensive care units.

RESULTS

Overall, 137,580 runners participated in long distance races during the study period. There were only 2 serious cardiac events (1 myocardial infarction and 1 hypotensive supraventricular tachyarrhythmia), neither of which were fatal or life threatening. In contrast, there were 21 serious cases of heat stroke, including 2 that were fatal and 12 that were life threatening. One of the heat stroke fatalities presented with cardiac arrest without previous warning.

CONCLUSIONS

In our cohort of athletes participating in endurance sports, for every serious cardiac adverse event, there were 10 serious events related to heat stroke. One of the heat stroke-related fatalities presented with unheralded cardiac arrest. Our results put in a different perspective the ongoing debate about the role of pre-participation electrocardiographic screening for the prevention of sudden death in athletes.

Sports-related sudden cardiac death in a competitive and a noncompetitive athlete population aged 12 to 49 years: data from an unselected nationwide study in Denmark

BACKGROUND

Preparticipation screening programs have been suggested to reduce the numbers of sports-related sudden cardiac deaths (SrSCD).

OBJECTIVE

The purpose of this study was to identify and characterize all SrSCD aged 12-49 years and to address the difference in incidence rates between competitive and noncompetitive athletes.

METHODS

All deaths among persons aged 12-49 years from 2007-2009 were included. Death certificates were reviewed. History of previous admissions to hospital was assessed, and discharge summaries and autopsy reports were read. Sudden cardiac deaths (SCDs) and SrSCD cases were identified.

RESULTS

In the 3-year period, there were 881 SCDs, of which we identified 44 SrSCD. In noncompetitive athletes aged 12-35 years, the incidence rate of SrSCD was 0.43 (95% confidence interval [CI] 0.16-0.94) per 100,000 athlete person-years vs 2.95 (95% CI 1.95-4.30) in noncompetitive athletes aged 36-49 years. In competitive athletes, the incidence rate of SrSCD was 0.47 (95% CI 0.10-1.14) and 6.64 (95% CI 2.86-13.1) per 100,000 athlete person-years in those aged 12-35 years and 36-49 years, respectively. The incidence rate of SCD in the general population was 10.7 (95% CI 10.0-11.5) per 100.000 person-years.

CONCLUSION

The incidence rates of SrSCD in noncompetitive and competitive athletes are not different. The study showed an increase in the incidence rate of SrSCD in persons aged 36-49 years in both noncompetitive and competitive athletes compared to those aged 12-35 years. Importantly, SCD in the general population is much more prevalent than is SrSCD in all age groups.

Impact of ethnicity on cardiac adaptation to exercise

The increasing globalization of sport has resulted in athletes from a wide range of ethnicities emerging onto the world stage. Fuelled by the untimely death of a number of young professional athletes, data generated from the parallel increase in preparticipation cardiovascular evaluation has indicated that ethnicity has a substantial influence on cardiac adaptation to exercise. From this perspective, the group most intensively studied comprises athletes of African or Afro-Caribbean ethnicity (black athletes), an ever-increasing number of whom are competing at the highest levels of sport and who often exhibit profound electrical and structural cardiac changes in response to exercise. Data on other ethnic cohorts are emerging, but remain incomplete. This Review describes our current knowledge on the impact of ethnicity on cardiac adaptation to exercise, starting with white athletes in whom the physiological electrical and structural changes--collectively termed the 'athlete's heart'--were first described. Discussion of the differences in the cardiac changes between ethnicities, with a focus on black athletes, and of the challenges that these variations can produce for the evaluating physician is also provided. The impact of ethnically mediated changes on preparticipation cardiovascular evaluation is highlighted, particularly with respect to false positive results, and potential genetic mechanisms underlying racial differences in cardiac adaptation to exercise are described.