From the Guidelines
Cardiac death due to exercise is a significant risk for individuals with underlying genetic heart diseases, and high-intensity exercise can trigger malignant ventricular arrhythmias, leading to cardiac arrest and sudden cardiac death (SCD) in at-risk individuals. The most common causes of SCD during exercise include hypertrophic cardiomyopathy (HCM), arrhythmogenic right ventricular cardiomyopathy (ARVC), and other genetic heart diseases 1. To reduce the risk of cardiac death during exercise, individuals should undergo pre-participation screening, which includes a medical history, physical examination, and sometimes an electrocardiogram (ECG) or echocardiogram.
Some key points to consider:
- Individuals with known heart conditions or risk factors should start exercise programs gradually and avoid sudden intense exertion without proper conditioning 1.
- Warning signs such as chest pain, unusual shortness of breath, dizziness, or palpitations during activity should be taken seriously, and individuals should seek medical attention immediately if they experience any of these symptoms.
- Those with known heart conditions should follow their cardiologist's specific recommendations regarding exercise limitations.
- Automated external defibrillators (AEDs) at exercise facilities and prompt CPR can significantly improve survival if cardiac arrest occurs.
- The risk of exercise-related cardiac death must be balanced against the substantial cardiovascular benefits of regular physical activity, which generally far outweigh the risks for most people 1.
- Individuals over 35 should be particularly mindful of coronary artery disease risk factors and consider more comprehensive screening before beginning vigorous exercise programs.
It is essential for individuals to be aware of their underlying heart conditions and take necessary precautions to minimize the risk of cardiac death during exercise. By taking a cautious approach and following guidelines, individuals can reduce their risk of cardiac death during exercise and enjoy the many benefits of regular physical activity.
From the Research
Cardiac Death Due to Exercise
- Cardiac death due to exercise is a significant concern, with studies suggesting that physical activity can trigger sudden cardiac death in individuals with underlying heart conditions 2, 3.
- The risk of sudden cardiac death during exercise is relatively low, but it can be higher in individuals with certain underlying conditions, such as hypertrophic cardiomyopathy and coronary artery disease 2.
- Regular physical exercise is recommended for lowering the risk of coronary events and all-cause mortality, but the relative effectiveness and hierarchy of different types of physical activity remain unclear 4.
- Extreme exercise can place a large hemodynamic stress on the heart, leading to cardiac remodeling and potentially increasing the risk of arrhythmias, coronary atherosclerosis, and sudden cardiac death 5.
Risk Factors
- Age is a significant risk factor, with the risk of sudden cardiac death increasing with aging (>35 years old) 2.
- Underlying heart conditions, such as hypertrophic cardiomyopathy and coronary artery disease, can increase the risk of sudden cardiac death during exercise 2, 3.
- The prevalence of coronary atherosclerosis is higher in athletes than in sedentary subjects with comparable risk profiles, but coronary plaques in physically active subjects appear more stable, reducing the risk of rupture and subsequent myocardial ischemia 2.
Prevention
- Preparticipation screening and annual follow-up are recommended for individuals who wish to practice moderate- to high-intensity exercise 2.
- Habitual physical activity can reduce the overall risk of myocardial infarction and sudden coronary death by preventing the development of coronary artery disease and progression of coronary atherosclerotic lesions 3.
- A high level of physical activity may reduce the risk of sudden cardiac death in the general population, with a summary relative risk of 0.52 (95% CI: 0.45-0.60) for highest vs. lowest level of physical activity 6.