**9. SCD prevention in athletes**

Solutions to this problem vary from country to country. In the USA, a group of American Heart Association (AHA) experts has proposed 12 steps that can help in the prevention of SCD in athletes at the initial screening stage [25]. These include the following conditions and medical history features:

Medical history:


Family history:


Physical examination:


It is noteworthy that an ECG is not included in this screening list. Supporting this approach, the guideline authors note that the rates of SCD in athletes in the USA and Italy (where an ECG is a compulsory component of the medical checkup in athletes before training) are about the same. A prospective cohort study in individuals aged below 36 years engaged in competitive sports was conducted in the Italian region of Veneto between 1979 and 1999. The most frequent cause of SCD in the study was ARVC (24%), followed by ischemic heart disease of atherosclerotic etiology (20%), abnormal outlet of coronary arteries (14%), and mitral valve prolapse (12%) [2]. Among older athletes (> 35–40 years), more than half of the cases of SCD were associated with ischemic heart disease, as in the general population.

**57**

*Sudden Cardiac Death in Young Athletes DOI: http://dx.doi.org/10.5772/intechopen.90627*

this study was USD 8000 (26).

changes, etc.

may be reduced almost twofold (USD 44,000).

changes of ECG—long or short QT and others [29, 30].

Some other American studies support the use of an ECG as part of a medical checkup of athletes at the early stages. A large study of 5615 young athletes conducted in Nevada (USA) demonstrated that the sensitivity of an ECG in the identification of serious cardiovascular pathology was 70% compared to 3% in the group of athletes where only a medical history and physical examination were used [26]. The specificity of ECG was 97.4%. Only 0.4% (22 of 5615) were withdrawn from sporting competitions. The estimated "cost" of a life saved by using only clinical and medical history data in this study was USD 84,000, while by adding an ECG, it

In the Japanese study [27], the researchers evaluated ECG screening results in 68,503 school students, and the SCD incidence in adolescents involved in competitive sports was on average 1.32 per 100,000 per year. Three deaths occurred in children without preceding syncope or SCD cases in the family history. In one 14-year-old boy, HCM had been identified earlier, at the pre-screening stage, and he was withdrawn from the sport, but he still died suddenly while jogging. In two other cases (13- and 16-year-old boys), SCD occurred while playing handball and basketball, and both had a normal ECG, and no pathological changes were identified during autopsy. The estimated "cost" of a life saved by using ECG screening in

Together with history and physical examination, the mandatory instrumental part of the cardiac examination in members of Russian junior national teams (less 18 years old) consists of a 12-lead resting ECG (with using original normal ECG criteria, which were elaborated at 500 young elite athletes) [28], EchoCG, and bicycle ergometry or treadmill test. A more thorough examination (Holter monitoring, analysis of heart rate turbulence, ventricular late potentials, magnetic resonance therapy, tilt test, etc.) depends on the changes detected at the preliminary stage, as well as medical history features, such as syncope, sudden death in the family, ECG

Despite a rather sizable document, it seems to us that for so-called elite athletes in high-level sports, it would be beneficial to include Holter monitoring, for special indication in athletes with syncope, arrhythmias, palpitation, and pathological

The European experience, which formed the basis for the International Olympic Committee recommendations, includes gathering a detailed medical history with an emphasis placed on the identification of complaints of potentially arrhythmogenic origin (palpitations, heart pain, etc.), syncope, cardiovascular disease, and cases of SCD in the family, especially at a young (under 50 years) age, and physical and ECG examinations, especially focusing on abnormal heart murmurs, alterations in blood pressure, ECG criteria of heart chamber hypertrophy, signs of myocardial ischemia, shortening or lengthening of the QT and PR intervals, and ventricular and supraventricular tachyarrhythmias [2]. The use of such screening, including an ECG in assessing the risk of SCD for 25 years in Italy, has shown that the incidence of SCD in young athletes aged 12–35 years engaged in competitive sports declined from 3.6 SCD cases per 100,000 per year (one death per 27,777 athletes) in 1979–1981 to 0.4 deaths per 100,000 per year (one death per 250,000 athletes) in 2003–2004. In general, SCD in athletes included in the screening decreased by 89%, whereas the incidence of SCD in the population not covered by the screening has not changed during the period [2]. This was due primarily to an increase in early detection and withdrawal from competitive sports of young people suffering from HCM, ARVC, and dilated cardiomyopathy (from 4.4% in 1979 to 9.4% in 2004). ECG changes may be the only early marker of a risk of life-threatening arrhythmias and SCD in athletes. However, the interpretation of ECG in athletes has its own peculiarities; any potentially life-threatening changes may be affected by conditions specific

#### *Sudden Cardiac Death in Young Athletes DOI: http://dx.doi.org/10.5772/intechopen.90627*

*Sudden Cardiac Death*

for cardiac conduction system diseases [6].

1.Chest pain/discomfort on exertion

2.Sudden fainting/presyncope

3.Vertigo (dizziness) on exertion

the following conditions and medical history features:

parents, brothers, sisters, and grandparents)

2.Cardiovascular disease in close relatives under 50 years

**9. SCD prevention in athletes**

Medical history:

4.Heart murmurs

Family history:

Physical examination:

2.Marfan syndrome manifestations

3.Sitting BP measurements

1.Femoral pulse

the general population.

the risk of SCD is significantly higher in athletes than in nonathletes with the same heart condition in the general population—by more than 5 times for ARVC, 2.6 times for coronary artery disease, 1.5 times for myocarditis, and more than 2 times

Solutions to this problem vary from country to country. In the USA, a group of American Heart Association (AHA) experts has proposed 12 steps that can help in the prevention of SCD in athletes at the initial screening stage [25]. These include

5.High blood pressure (> 140/90 or more on the first measurement)

1.Sudden death of the first-degree relatives aged under 50 years (first of all

3.Cardiomyopathy, LQTS, Marfan syndrome, ARVC, or other conditions with a risk of life-threatening arrhythmias or coronary artery disease in relatives

It is noteworthy that an ECG is not included in this screening list. Supporting

this approach, the guideline authors note that the rates of SCD in athletes in the USA and Italy (where an ECG is a compulsory component of the medical checkup in athletes before training) are about the same. A prospective cohort study in individuals aged below 36 years engaged in competitive sports was conducted in the Italian region of Veneto between 1979 and 1999. The most frequent cause of SCD in the study was ARVC (24%), followed by ischemic heart disease of atherosclerotic etiology (20%), abnormal outlet of coronary arteries (14%), and mitral valve prolapse (12%) [2]. Among older athletes (> 35–40 years), more than half of the cases of SCD were associated with ischemic heart disease, as in

**56**

Some other American studies support the use of an ECG as part of a medical checkup of athletes at the early stages. A large study of 5615 young athletes conducted in Nevada (USA) demonstrated that the sensitivity of an ECG in the identification of serious cardiovascular pathology was 70% compared to 3% in the group of athletes where only a medical history and physical examination were used [26]. The specificity of ECG was 97.4%. Only 0.4% (22 of 5615) were withdrawn from sporting competitions. The estimated "cost" of a life saved by using only clinical and medical history data in this study was USD 84,000, while by adding an ECG, it may be reduced almost twofold (USD 44,000).

In the Japanese study [27], the researchers evaluated ECG screening results in 68,503 school students, and the SCD incidence in adolescents involved in competitive sports was on average 1.32 per 100,000 per year. Three deaths occurred in children without preceding syncope or SCD cases in the family history. In one 14-year-old boy, HCM had been identified earlier, at the pre-screening stage, and he was withdrawn from the sport, but he still died suddenly while jogging. In two other cases (13- and 16-year-old boys), SCD occurred while playing handball and basketball, and both had a normal ECG, and no pathological changes were identified during autopsy. The estimated "cost" of a life saved by using ECG screening in this study was USD 8000 (26).

Together with history and physical examination, the mandatory instrumental part of the cardiac examination in members of Russian junior national teams (less 18 years old) consists of a 12-lead resting ECG (with using original normal ECG criteria, which were elaborated at 500 young elite athletes) [28], EchoCG, and bicycle ergometry or treadmill test. A more thorough examination (Holter monitoring, analysis of heart rate turbulence, ventricular late potentials, magnetic resonance therapy, tilt test, etc.) depends on the changes detected at the preliminary stage, as well as medical history features, such as syncope, sudden death in the family, ECG changes, etc.

Despite a rather sizable document, it seems to us that for so-called elite athletes in high-level sports, it would be beneficial to include Holter monitoring, for special indication in athletes with syncope, arrhythmias, palpitation, and pathological changes of ECG—long or short QT and others [29, 30].

The European experience, which formed the basis for the International Olympic Committee recommendations, includes gathering a detailed medical history with an emphasis placed on the identification of complaints of potentially arrhythmogenic origin (palpitations, heart pain, etc.), syncope, cardiovascular disease, and cases of SCD in the family, especially at a young (under 50 years) age, and physical and ECG examinations, especially focusing on abnormal heart murmurs, alterations in blood pressure, ECG criteria of heart chamber hypertrophy, signs of myocardial ischemia, shortening or lengthening of the QT and PR intervals, and ventricular and supraventricular tachyarrhythmias [2]. The use of such screening, including an ECG in assessing the risk of SCD for 25 years in Italy, has shown that the incidence of SCD in young athletes aged 12–35 years engaged in competitive sports declined from 3.6 SCD cases per 100,000 per year (one death per 27,777 athletes) in 1979–1981 to 0.4 deaths per 100,000 per year (one death per 250,000 athletes) in 2003–2004. In general, SCD in athletes included in the screening decreased by 89%, whereas the incidence of SCD in the population not covered by the screening has not changed during the period [2]. This was due primarily to an increase in early detection and withdrawal from competitive sports of young people suffering from HCM, ARVC, and dilated cardiomyopathy (from 4.4% in 1979 to 9.4% in 2004). ECG changes may be the only early marker of a risk of life-threatening arrhythmias and SCD in athletes. However, the interpretation of ECG in athletes has its own peculiarities; any potentially life-threatening changes may be affected by conditions specific

only to sports. For instance, the QT interval is longer in athletes [31]; its shortening was revealed when using some anabolic agents in athleticism [32]. The emergence of new, noninvasive methods of electrocardiological diagnostics seems to be promising for risk group stratification in sports. Certain features of the QT interval frequency adaptation [33] and microvolt T-wave alternans [34, 35] may aid in the stratification of athletes with electrical instability of the heart and an increased risk of life-threatening arrhythmias and SCD, and they may differentiate pathological and non-pathological transformations of the athlete's heart. The 2015 European Society of Cardiology Guidelines for the prevention of SCD proposes the following algorithm of SCD prevention in athletes [9]:


#### **Prevention of sudden cardiac death in athletes (ESC).**

*ESC = European Society of Cardiology, CMR = cardiac magnetic resonance, ECG = electrocardiogram, SCD = sudden cardiac death, SCORE = systematic coronary risk evaluation, Class = class of recommendation (I, IIa, IIb, III), Level = level of evidence (A, B, C), Reference = reference(s) supporting recommendations.*

The main fatal arrhythmia leading to death is ventricular fibrillation. If this develops, the most effective method for treatment is electric defibrillation. As was shown above, the majority of SCD cases in athletes occur during engagement in sports [2, 6], in contrast to similar data from nonathletes where up to 80% of SCD cases are registered at home [29, 30]. This enables the creation of a system of more effective medical aid in the first few minutes after cardiac arrest during physical activity. According to the US National Registry of Sudden Death, in cases of sudden death associated with exercise in young people over the period from 2000 and 2006, the percentage of survival in the latter 3 years of the study almost doubled compared to the first 3 years, reaching 14–17% [39]. And only in 2006, similar rates of successful recovery after cardiac arrest were achieved by using automatic external defibrillators (AED), which are publicly available, and electrical defibrillation performed by specialized emergency teams [39]. There were many reports of successful defibrillation in cardiac arrest in athletes during physical activity or competition [19].

Labor costs, effectiveness, and economic costs of comprehensive preventive screening in 785 athletes aged 5–65 years who are engaged in high-intensity sports [38] were also evaluated. As a result of this screening, newly diagnosed

**59**

**Author details**

Leonid Makarov

*Sudden Cardiac Death in Young Athletes DOI: http://dx.doi.org/10.5772/intechopen.90627*

during major competitions [37].

cardiovascular diseases were identified in 2.8% of athletes; economic costs were USD 199 per athlete. The researchers consider such a screening to be warranted and affordable. The guidelines also highlight the importance of training coaches and staff in sports centers on the actions needed in case of emergency, performing cardiopulmonary resuscitation and the use of AED, both in athletes and spectators

Regular physical activity in the young is the most effective prophylactic for all cardiac diseases, but SCD in young athletes remains rare but a very tragic event for the family, friends, and society, which can arise deep negative resonance media about sports. Prevention of SCD in the young athletes is based on careful preparticipation screening of young athletes for identifying diseases with risk of SCD during sports activity and to elaborate a detailed plan of the first aid during and after cardiac events in sports competition and any sports activity, it is necessary to perform careful pre-participation screening of young athletes for identifying diseases with high risk of SCD during sports activity and to elaborate a detailed plan of the first aid after cardiac events during sports competition and any sports activity.

Center for Syncope and Cardiac Arrhythmias in Children and Adolescents, Central Children Clinical Hospital Russian Federal Medico Biology Agency (FMBA of Russia), Academy of Postgraduated Education FMBA of Russia, Moscow, Russia

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

\*Address all correspondence to: dr.leonidmakarov@mail.ru

provided the original work is properly cited.

#### *Sudden Cardiac Death in Young Athletes DOI: http://dx.doi.org/10.5772/intechopen.90627*

*Sudden Cardiac Death*

algorithm of SCD prevention in athletes [9]:

of SCD is recommended in athletes

recommended

recommended

and resting ECG

defibrillators

**Prevention of sudden cardiac death in athletes (ESC).**

Careful history taking to uncover underlying cardiovascular disease, rhythm disorder, and syncopal episodes or family history

Upon identification of ECG abnormalities suggestive of structural heart disease, echocardiography and/or CMR imaging is

Upon identification of ECG abnormalities suggestive of structural heart disease, echocardiography and/or CMR imaging is

Physical examination and resting 12-lead ECG should be considered for pre-participation screening in younger athletes

Middle-aged individuals engaging in high-intensity exercise should be screened with history, physical examination, SCORE,

Staff at sporting facilities should be trained in cardiopulmonary resuscitation and on the appropriate use of automatic external

only to sports. For instance, the QT interval is longer in athletes [31]; its shortening was revealed when using some anabolic agents in athleticism [32]. The emergence of new, noninvasive methods of electrocardiological diagnostics seems to be promising for risk group stratification in sports. Certain features of the QT interval frequency adaptation [33] and microvolt T-wave alternans [34, 35] may aid in the stratification of athletes with electrical instability of the heart and an increased risk of life-threatening arrhythmias and SCD, and they may differentiate pathological and non-pathological transformations of the athlete's heart. The 2015 European Society of Cardiology Guidelines for the prevention of SCD proposes the following

**Recommendations Class Level Reference**

I С This panel of

I С This panel of

IIa С This panel of

IIa С This panel of

IIa С [36]

IIa С [37, 38]

experts

experts

experts

experts

The main fatal arrhythmia leading to death is ventricular fibrillation. If this develops, the most effective method for treatment is electric defibrillation. As was shown above, the majority of SCD cases in athletes occur during engagement in sports [2, 6], in contrast to similar data from nonathletes where up to 80% of SCD cases are registered at home [29, 30]. This enables the creation of a system of more effective medical aid in the first few minutes after cardiac arrest during physical activity. According to the US National Registry of Sudden Death, in cases of sudden death associated with exercise in young people over the period from 2000 and 2006, the percentage of survival in the latter 3 years of the study almost doubled compared to the first 3 years, reaching 14–17% [39]. And only in 2006, similar rates of successful recovery after cardiac arrest were achieved by using automatic external defibrillators (AED), which are publicly available, and electrical defibrillation performed by specialized emergency teams [39]. There were many reports of successful defibrillation in cardiac arrest in athletes during physical activity or

*ESC = European Society of Cardiology, CMR = cardiac magnetic resonance, ECG = electrocardiogram, SCD = sudden cardiac death, SCORE = systematic coronary risk evaluation, Class = class of recommendation (I, IIa, IIb, III), Level = level of evidence (A, B, C), Reference = reference(s) supporting recommendations.*

Labor costs, effectiveness, and economic costs of comprehensive preventive screening in 785 athletes aged 5–65 years who are engaged in high-intensity sports [38] were also evaluated. As a result of this screening, newly diagnosed

**58**

competition [19].

cardiovascular diseases were identified in 2.8% of athletes; economic costs were USD 199 per athlete. The researchers consider such a screening to be warranted and affordable. The guidelines also highlight the importance of training coaches and staff in sports centers on the actions needed in case of emergency, performing cardiopulmonary resuscitation and the use of AED, both in athletes and spectators during major competitions [37].

Regular physical activity in the young is the most effective prophylactic for all cardiac diseases, but SCD in young athletes remains rare but a very tragic event for the family, friends, and society, which can arise deep negative resonance media about sports. Prevention of SCD in the young athletes is based on careful preparticipation screening of young athletes for identifying diseases with risk of SCD during sports activity and to elaborate a detailed plan of the first aid during and after cardiac events in sports competition and any sports activity, it is necessary to perform careful pre-participation screening of young athletes for identifying diseases with high risk of SCD during sports activity and to elaborate a detailed plan of the first aid after cardiac events during sports competition and any sports activity.
