Protagonist: Routine screening of all athletes prior to participation in competitive sports should be mandatory to prevent sudden cardiac death

Can exercise test intensity and modality affect the prevalence of arrhythmic events in young athletes?

Pre-participation screening is performed to identify underlying cardiac conditions that may also lead to sudden cardiac death. Our aim is to compare submaximal Harvard Step Test (HST) with incremental Maximal Exercise Test (MET) on treadmill to induce and detect arrhythmias in younger athletes. A total of 1000 athletes (mean age 14.6 ± 4.7 years) were evaluated, 500 with MET and 500 with HST, all with continuous ECG monitoring until three minutes of recovery. Pre-test evaluation includes medical history, clinical evaluation and resting electrocardiogram. Ventricular and/or supraventricular arrhythmias were observed in 2.6% of athletes performing HST and in 8.4% during MET (p < 0.001). Incidence of arrhythmias remained higher for MET also considering separately exercise phase (0.8% vs. 5.2%; p < 0.001) and recovery phase (2.0% vs. 6.0%; p < 0.01). No gender differences were observed. Results suggest that MET induces more arrhythmias than submaximal HST, regardless of test phase. Higher test intensity and longer exercise duration might influence test outcomes, making MET more arrhythmogenic.

Generalized Poincaré plots analysis of heart period dynamics in different physiological conditions: Trained vs. untrained men

Background

Recently we proposed a new method called generalized Poincaré plot (gPp) analysis which gave a new insight into the pattern of neurocaridac control. In this study we examined potential of gPp method to reveal changes in cardiac neural control in young athletes during three conditions: supine rest, running and relaxation, with respect to untrained subjects.

Methods

This method is based on the quantification of Pearson’s correlation coefficients r(j, k), between symmetrical (j = k) and asymmetrical summed j previous and k following RR intervals up to the 100th order (j,k≤100).

Results

Differences between groups were obtained at all levels of this analysis. The main result is the significant difference of NAI, normalized index of asymmetry, between groups in running, which was originated in different positions of local maxima of r(j, k). Compared with untrained subjects, these findings indicate modified neural control and altered intrinsic heart rate behavior in athletes which are related to some kind of memory mechanism between RR intervals.

Conclusion

Obtained results provide great potential of gPp method analysis in the recognition of changes in neurocardiac control in healthy subjects. Further studies are needed for identification of altered cardiac regulatory mechanisms whose background may be useful in the evaluation of genesis of athletes neurocardiovascular pathology.

Pre-participation screening of asymptomatic athletes : "Don't do stupid stuff"

Catastrophic events, be it traffic accidents, natural disasters or homicides, always lead to scrutiny. Could we have seen the event coming and could it have been prevented? In the case of a sudden cardiac arrest of a seemingly healthy athlete the public outcry is not any different. Despite an intrinsic appeal for screening to prevent similar events, there is no evidence that justifies routine cardiovascular pre-participation screening of athletes. On balance, cardiovascular screening in athletes will most likely do more harm than good. Fatal exercise-related cardiac arrests do not occur very often. The true diagnostic yield of the pre-participation evaluation is not known and once a cardiac condition has been identified, the most appropriate intervention is often unclear. It follows that pre-participation screening of large groups of athletes without known cardiac disease will inevitably result in many false positive findings, while at the same time providing a false sense of security to those screened negative. Except for compelling reasons (e. g. cascade screening, research settings, professional athletes), physicians should not engage in routine examination of asymptomatic athletes to prevent cardiac events.

A survey of paediatricians on the use of electrocardiogram for pre-participation sports screening

Aim The aim of the present study was to determine general paediatrician knowledge, practices, and attitudes towards electrocardiogram (ECG) screening in school athletes during pre-participation screening exam (PPSE).

METHODS

Paediatricians affiliated with a tertiary children's hospital completed a survey about ECGs for PPSE.

RESULTS

In total, 205/498 (41%) responded; 92% of the paediatricians did not include an ECG as part of PPSE; 56% were aware of a case in which a student athlete in their own community had died of sudden unexplained death; 4% had an athlete in their practice die. Only 16% of paediatricians perform all 12 American Heart Association recommended elements of the PPSE. If any of these screening elements are abnormal, 69% obtain an ECG, 36% an echocardiogram, and 30% restrict patients from sports activity; 73% of them refer the patient to a cardiologist.

CONCLUSION

Most of the general paediatricians surveyed did not currently perform ECGs for PPSE. In addition, there was a low rate of adherence to performing the 12 screening elements recommended by the American Heart Association. They have trouble obtaining timely, accurate ECG interpretations, worry about potential unnecessary exercise restrictions, and cost-effectiveness. The practical hurdles to ECG implementation emphasise the need for a fresh look at PPSE, and not just ECG screening. Improvements in ECG performance/interpretation would be necessary for ECGs to be a useful part of PPSE.

Ethics of preparticipation cardiovascular screening for athletes

Preparticipation screening for unsuspected cardiovascular disease is a controversial topic in the medical and lay communities. Much attention has been directed towards young competitive athletes, particularly the proposed strategy of incorporating 12-lead electrocardiograms into the screening process, even on a national or worldwide basis. However, sudden deaths of young athletes owing to genetic or congenital heart diseases have a low incidence in the general population. Furthermore, young people not engaged in competitive sports can harbour the same conditions that cause sudden death in athletes, which has gone largely unrecognized. Notably, sudden deaths from these diseases are numerically far more common in the much larger population of nonathletes. In this Perspectives article, we propose that an ethical dilemma has emerged, raising the important public-health issue of whether young individuals should be arbitrarily excluded from potentially life-saving clinical screening evaluations because they do not engage in competitive sports programmes.

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.

The pre-sports cardiovascular evaluation: should it depend on the level of competition, the sport, or the state?

Sudden cardiac death (SCD) in an athlete is a rare but tragic event, and significant controversy exists regarding the most effective method to define those at highest risk. Recommendations of the American Heart Association require that a history and physical examination be used for preparticipation screening with an abnormal cardiac finding expected to prompt further evaluation. Given the lack of data documenting that electrocardiogram (ECG) screening in all competitive athletes is either feasible or appropriate, these same guidelines state that such screening is optional but not mandatory. The extremely low incidence of SCD events, in conjunction with the low sensitivity and specificity of ECG as a screening tool in athletes, contributes to this recommendation. Although these guidelines target all competitive athletes, however, there may be subgroups of athletes, based on age, level of competition, individual sport, or state of residence, for which mandatory ECG screening may be both appropriate and sensible. Given the lack of resolution of the ongoing ECG debate, it is perhaps reasonable to consider screening specific high-risk subgroups of athletes rather than continuing to dispute whether to screen all competitive athletes or none at all. Recent data suggest that such a program may be feasible and may provide a rationale basis for subsequent expansion of cardiovascular screening programs.

Can we prevent sudden cardiac death in young athletes: the debate about preparticipation sports screening

All high school athletes in the United States require a preparticipation screening examination. The American Heart Association recommends a focused history and physical examination. The European Society of Cardiology recommends that all examinations include an electrocardiogram (ECG). We review the risks and costs of screening, discuss legal ramifications and analyse the ethical implications of these considerations. There are too many unknown about ECG screening to require it as routine testing for all high school athletes.

CONCLUSION

Doctors must inform young athletes and their parents about the option of ECG screening and about the debate over its efficacy. Patients and parents may then choose to have an ECG or not. Mandatory universal screening is not warranted at this time.

Mandatory electrocardiographic screening of athletes to reduce their risk for sudden death proven fact or wishful thinking?

OBJECTIVES

The purpose of this study was to determine if pre-participation screening of athletes with a strategy including resting and exercise electrocardiography (ECG) reduces their risk for sudden death.

BACKGROUND

An increasing number of countries mandate pre-participation ECG screening of athletes for the prevention of sudden death. However, the evidence showing that such a strategy actually reduces the risk of sudden death in athletes is limited. We therefore analyzed the impact of the National Sport Law enacted in Israel in 1997-which mandates screening of all athletes with resting ECG and exercise testing-on the incidence of sudden death among competitive athletes.

METHODS

We conducted a systematic search of the 2 main newspapers in Israel to determine the yearly number of cardiac arrest events among competitive athletes. The size of the population at risk was retrieved from the Israel Sport Authority and was extrapolated to the changes in population size over time.

RESULTS

There were 24 documented events of sudden death or cardiac arrest events among competitive athletes during the years 1985 through 2009. Eleven occurred before the 1997 legislation and 13 occurred after it. The average yearly incidence of sudden death or cardiac arrest events was 2.6 events per 100,000 athlete-years. The respective averaged yearly incidence during the decade before and the decade after the 1997 legislation was 2.54 and 2.66 events per 100,000 person years, respectively (p = 0.88).

CONCLUSIONS

The incidence of sudden death of athletes in our study is within the range reported by others. However, mandatory ECG screening of athletes had no apparent effect on their risk for cardiac arrest.

Arrhythmia and right heart disease: from genetic basis to clinical practice

Historically, left ventricular cardiomyopathy and coronary heart disease have been regarded as the main causes of ventricular arrhythmia and sudden cardiac death. However, within last two decades, arrhythmias originating from the right ventricle have begun to attract the attention of the scientific world for a number of reasons. Ventricular arrhythmias originating from the right ventricle usually affect younger patients and can lead to sudden cardiac death. The pathophysiologic mechanism of these arrhythmias is not fully understood, which can leave room for a range of different interpretations. Moreover, the intriguing world of genetics is increasingly being drawn into the pathogenesis, diagnosis and prognosis of some of these arrhythmias. This review considers the pathogenesis, diagnosis and treatment of arrhythmogenic right ventricular cardiomyopathy or dysplasia (ARVD), Brugada syndrome, right ventricular outflow tract ventricular tachycardia, and arrhythmias in the right side of the heart due to congenital heart disease. In addition, because ventricular arrhythmias associated with right ventricular heart diseases such as Brugada syndrome and ARVD can explain up to 10-30% of sudden cardiac deaths in young adults in the general population and an even greater percentage in young athletes, this article contains a brief analysis of screening tests used before participation in sports, life-style modification, and treatment options for athletes affected by these conduction disorders.

Electrocardiogram testing during athletic preparticipation physical examinations

CONTEXT

Sudden cardiac death (SCD) is a relatively rare yet unfortunate risk of athletic participation. To reduce the incidence of SCD, electrocardiogram (ECG) use during athletic preparticipation examinations (PPEs) has been proposed to detect underlying cardiac abnormalities.

OBJECTIVE

To estimate the effectiveness of ECG use during athletic PPEs.

DESIGN

Epidemiologic modeling.

POPULATIONS

Public high school athletes.

DATA COLLECTION AND ANALYSIS

Estimates of ECG sensitivity (70%) and specificity (84%) were drawn from the literature, as was the estimate of overall prevalence of cardiac conditions relevant to SCD (0.3%). Participation rate by sex was determined from National Federation of State High School Associations data. Participation by ethnicity was assumed to be proportionate to the public high school attendance rates for grades 9 through 12 (18.4% African American). Population-specific ECG effectiveness (positive predictive value), estimated total costs, cost per year of life saved, and cost to identify 1 additional case were computed. Total annual PPE screening costs reflected a cardiologist's office visit, including echocardiogram for those athletes with a positive ECG screen.

RESULTS

The model predicted that 16% of all athletes would be expected to have a positive ECG, but only 1.3% of athletes with a positive ECG would have a cardiac abnormality capable of causing SCD, including hypertrophic cardiomyopathy, structural defects, and various conduction abnormalities. Total annual cost estimates for ECG screening and follow-up exceeded $126 million. Average cost per year of life saved across groups was $2693, and the cost to identify 1 additional case averaged $100 827. Compared with females, males had both lower cost per year of life saved and lower cost to identify 1 true case. Similarly, black males exhibited lower costs than white males. Across groups, false-positive ECG screening exams accounted for 98.8% of follow-up costs.

CONCLUSIONS

Large-scale, mass ECG testing would be a costly method to identify athletes with cardiac abnormalities. Targeting high-risk populations can increase the effectiveness of the ECG for athletic PPE screening.

Sudden death in persons younger than 40 years of age: incidence and causes

BACKGROUND

The problem of sudden death in the young is currently debated and measures for prevention are being evaluated worldwide. Information on the incidence and causes of sudden (cardiac) death in the young (1-40 years) is essential for the development of these preventive strategies.

METHODS

Incidence estimates and causes of death were determined using death certificate data of out-of-hospital sudden deaths recorded by Statistics Netherlands from 1996 to 2006. To define sudden death, International Classification of Diseases codes were selected based on a systematic review of the literature assessing the most common causes of sudden death in the young.

RESULTS

The incidence of sudden death was 2.07 (2.06-2.07 per 100 000 person-years). The incidence was higher for men (2.86 per 100 000 person-years) than for women (1.24 per 100 000 person-years) and increased by age. The majority of sudden deaths was of cardiac origin. Sudden cardiac death incidence was 1.62 (1.61-1.62 per 100 000 person-years). In 9% the cause of death remained unexplained.

CONCLUSION

The incidence of sudden death in the young is 2.07 per 100 000 person-years. Treatable cardiac causes (such as coronary atherosclerosis and inherited cardiac diseases) are often underlying for the sudden death. This information is helpful in the development of preventive strategies.

Recommendations for interpretation of 12-lead electrocardiogram in the athlete

Cardiovascular remodelling in the conditioned athlete is frequently associated with physiological ECG changes. Abnormalities, however, may be detected which represent expression of an underlying heart disease that puts the athlete at risk of arrhythmic cardiac arrest during sports. It is mandatory that ECG changes resulting from intensive physical training are distinguished from abnormalities which reflect a potential cardiac pathology. The present article represents the consensus statement of an international panel of cardiologists and sports medical physicians with expertise in the fields of electrocardiography, imaging, inherited cardiovascular disease, cardiovascular pathology, and management of young competitive athletes. The document provides cardiologists and sports medical physicians with a modern approach to correct interpretation of 12-lead ECG in the athlete and emerging understanding of incomplete penetrance of inherited cardiovascular disease. When the ECG of an athlete is examined, the main objective is to distinguish between physiological patterns that should cause no alarm and those that require action and/or additional testing to exclude (or confirm) the suspicion of an underlying cardiovascular condition carrying the risk of sudden death during sports. The aim of the present position paper is to provide a framework for this distinction. For every ECG abnormality, the document focuses on the ensuing clinical work-up required for differential diagnosis and clinical assessment. When appropriate the referral options for risk stratification and cardiovascular management of the athlete are briefly addressed.