Sports cardiology: preventing sudden cardiac death

Sports activities and cardiovascular system change

Sports activity is generally considered to be beneficial to health. The World Health Organization (WHO) recommends physical activity as part of a healthy lifestyle. Sports activities significantly affect the cardiovascular system. A number of studies show that they significantly reduce the risk of cardiovascular disease as well as decrease cardiovascular mortality. This review discusses changes in various cardiovascular parameters in athletes - vagotonia/bradycardia, hypertrophy of heart, ECG changes, blood pressure, and variability of cardiovascular parameters. Because of its relationship to the cardiovascular system, VO2max, which is widely used as an indicator of cardiorespiratory fitness, is also discussed. The review concludes with a discussion of reactive oxygen species (ROS) and oxidative stress, particularly in relation to changes in the cardiovascular system in athletes. The review appropriately summarizes the above issues and points out some new implications.

[The athlete's ECG : What is normal or abnormal?]

BACKGROUND

The electrocardiogram (ECG) has become a mobile and cost-effective routine assessment tool to risk stratify leisure-time and professional athletes during preparticipation screening. A central goal is the reduction of sudden cardiac death in sports through early recognition of the most prevalent underlying cardiac pathologies, e.g., hereditary cardiomyopathies or primary arrhythmias.

METHODS

Continuous evolution of the first ECG criteria for athletes, presented in 2010 by the European Society of Cardiology (ESC), has helped to improve the specificity of the criteria to both detect cardiac pathologies in early stages and differentiate from physiologic adaptation of the athlete's heart. Thus, the risk of false-positive findings and erroneous stigmatizations of athletes has been successfully reduced.

CONCLUSION

This review article intends to trace back the changes of the ECG criteria in the light of a growing body of scientific evidence over the last 15 years, to present the key messages of the current International ECG criteria from 2017 and to identify some of the remaining challenges that wait to be answered by physicians in the field of sports medicine and sports cardiology.

Sudden cardiac arrest in sports: a video analysis

Objectives

Information about sudden cardiac arrest (SCA) in sports arises from registries, insurance claims and various reports. Analysing video footage of SCA during sports for scientific purposes has scarcely been done. The objective of this study was to examine videotaped SCA in athletes to better understand the mechanisms of SCA.

Methods

Publicly available online video databases were searched for videos displaying SCA in athletes.

Results

Thirty-five online videos (26 from professional and 9 from amateur sport; 34 male victims) were obtained. Twenty-one events resulted in survival and 14 in sudden cardiac death. Level of physical activity prior to SCA was assessable in 28 videos; 19 events occurred during low-intensity, 6 during moderate-intensity and 3 during high-intensity activity. SCA predominately occurred during low-intensity compared with both moderate-intensity and high-intensity activities (p<0.01). In 26/35 videos, it was possible to observe if resuscitation was provided. Resuscitation was carried out in 20 cases; cardiopulmonary resuscitation (CPR) alone (8 cases), CPR+defibrillation (10), cardiac thump (1) or shock from an implantable cardioverter defibrillator (1). Thirteen of the 20 cases with resuscitation received an intervention within 1 min after collapse. Survival was high when intervention occurred within 1 min (12/13) compared with those who received delayed (3/5) or no intervention (1/6). Associated signs of SCA such as agonal respirations and seizure-like movements were observed in 66% of the cases.

Conclusions

SCA during sport most often occurred during low-intensity activity. Prompt intervention within 1 min demonstrated a high survival rate and should be the standard expectation for witnessed SCA in athletes.