Statistics from Altmetric.com
The sudden and unexpected death of an apparently healthy young athlete is relatively uncommon (0.5–2.1/100 000 athletes per year), but the catastrophic nature of these events mandates the medical community to adopt more widespread and extensive preparticipation cardiovascular screening (PPS).1 2
PPS in young athletes (<35 years old) is a systemic method to identify athletes at risk for life-threatening cardiovascular events.3 Excluding these athletes from competitive sports participation leads to a reduction in the incidence of exercise related sudden cardiac death (SCD).3 According to the Italian law all young competitive athletes (about 10% of the population) have been screened in a nationwide screening program in Italy for over 25 years. In the Veneto region in northern Italy, this resulted in a decrease of SCD among young athletes of 89% (from 3.6/100 000 per year in 1979 to 0.4/100 000 athletes per year in 2004).3 This reduction was predominantly attributed to identification of cardiomyopathy and electrical disease, and by excluding these athletes from competitive sports participation. The number of false positive test results was reported at 7%.3
The “Italian experience” is at the moment the only prospective population based study regarding PPS. This Italian protocol was adopted by the European Society of Cardiology (ESC) as the “common European protocol”, and by the International Olympic Committee (IOC), the international soccer association Fédération Internationale de Football Association (FIFA) and the international federation for cyclists Union Cycliste Internationale (UCI) as the “Lausanne protocol”.4 5 Contrary to the guidelines of the American Heart Association, the common European and the Lausanne protocols include a 12-lead resting electrocardiogram (ECG).6 There have been several debates concerning the different approaches in the USA and European Union (EU).
The ECG in athletes is an expression of cardiac adaptation to the type of sports, intensity and level of training, and duration of sports participation. The most common training related variations are bradyarrhythmias, prolonged PR interval, increased QRS voltages and early repolarisation. Only 2% to 15% of ECGs performed on athletes require additional cardiovascular evaluation, and this is largely dependent on the criteria chosen to interpret the ECGs and define “abnormal”.3 4 7 The surface ECG in young athletes can be a clue for “silent cardiac disease” in about 60% of cases. Electrical cardiac diseases, such as long QT syndrome, short QT syndrome, Brugada syndrome and Lev Lenegre syndrome, and Wolf Parkinson White syndrome (WPW), hypertrophic cardiomyopathy (HCM) and arrhythmogenic right ventricular cardiomyopathy (ARVC) can be identified on the resting ECG. HCM is still the main cause of SCD in young athletes in the US (36%) with the highest rate in African–Americans.4 8 The resting ECG fails to detect catecholaminergic polymorphic ventricular tachycardia (CPVT), coronary anomaly (responsible for 13.7% to 16% of SCD) and premature coronary disease. In suspected cases an exercise ECG or advanced cardiac imaging may be necessary. Other important non-congenital and non-inherited causes of SCD in athletes (of all ages) are myocarditis and commotiocordis (blunt chest trauma) (responsible for 4% of SCD).9 These two acquired cardiac diseases cannot be prevented by screening methods.
With regard to older athletes (>35 years old), there is limited data on screening. The principal cause of SCD in this group is acquired coronary artery disease, often presenting itself as exercise induced ventricular fibrillation. Therefore an exercise ECG should be considered in the PPS of older competitive athletes.10 In a 3-year prospective observational study, 66% of older athletes referred for additional cardiovascular evaluation after PPS by sports doctors had cardiovascular problems such as arrhythmia (17%), coronary artery disease (7%), or a high-risk profile with two or more major risk factors for cardiovascular disease (11%).11 Hypertension (23%) and atrial fibrillation (10%) were frequently seen in this study, and 4.9% of those referred needed invasive treatment such as rhythm ablation, coronary revascularisation and valve replacement.11
In the “common European protocol” criteria for what can be accepted as a normal ECG in Caucasian athletes are mentioned. However, criteria for normal values in different age groups of young athletes and in other ethnic groups, especially the black population, are lacking.4 The evidence is growing for what can be regarded as normal for duration and morphology of the ECG findings in athletes, resulting in a lower false positive rate for presumed pathology and less unnecessary additional cardiovascular evaluation that may result in unindicated exclusion from sports participation (1.5% to 4%).12 The criteria mentioned in the common European protocol have to be reconsidered to increase the possibility of discriminating between physiological electrical cardiac adaptation and underlying pathology in athletes.13
The US and the EU protocols both give recommendations to guide sports participation or disqualification in athletes with identified cardiovascular disorders6 14 When an athlete is not eligible for sports participation the psychological impact is of great consequence, and there may be financial or career implications as well. Caution should be taken not to erroneously exclude an athlete with a false positive finding of cardiovascular disease. The athlete should be able to go for re-evaluation by consulting another cardiologist with expertise in this field to reduce unnecessary exclusion from sports participation. If the diagnosis is confirmed again, the athlete should be excluded from competitive sports participation based on existing guidelines. However, if there is a treatable disease the athlete should be able to have further evaluation after adequate disease management. Therefore the recommendations for sports participation should be based on a true definitive diagnosis, with adequate risk stratification, and not on the presumed diagnosis. Risk stratification in athletes, according to the EU recommendations, is based on the identified disease. Risk stratification should be more precise with the aid of gene typing, reducing unnecessary (complete) exclusion from sports participation. In cases of positive gene testing without clinical expression of the disease, recommendation for sports participation should be on an individual basis with respect to risk stratification for the disease in question.
In many countries such as the USA and The Netherlands, the PPS is performed by sports doctors and primary healthcare practitioners. With proper education, this allows a greater infrastructure to conduct a comprehensive PPS, including ECGs, in all athletes. Once the ECG criteria for normal variations in athletes are revised and implemented these doctors can be adequately trained in recognising electrocardiographic physiological adaptation and pathology.13 In cases of an abnormal ECG suspicious for pathological cardiovascular disease, the athlete should be referred for additional evaluation to a specialised centre with expertise in sports cardiology. This makes a universal screening program possible.
While a single protocol to screen young athletes has not been universally adopted, there is general agreement regarding the need for preparticipation cardiovascular screening in young athletes. The EU screening protocol (and the Lausanne protocol) including a 12-lead resting ECG meets the World Health Organization (WHO) criteria for screening and is evidence based.3 The ECG is simple, efficient, safe, non-invasive, accurate, validated and inexpensive. Healthcare and sport governing bodies should support this universal screening protocol in all young athletes. However, caution must be taken not to exclude an athlete on false positive reasons. Continued research in this field of young and older athletes is clearly warranted.
Competing interests None.
Provenance and peer review Commissioned; not externally peer reviewed.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.