I’m sure we’ve all heard the phrase “sedentary is the equivalent of chronic suicide”, and several previous studies have shown that spending more time exercising (and less time being sedentary) is associated with health benefits, not only in terms of improving cardiorespiratory endurance, but also in terms of improving cardiovascular disease-related risk factors.
However, inappropriate exercise can lead to sudden cardiac death (SCD) and myocardial infarction and other malignant cardiovascular events. So what can be done to prevent sports-related sudden death or cardiovascular accidents?
Cardiovascular risk stratification and assessment is recommended before exercise
1. Exercise-related cardiovascular health risk stratification
The consensus points out that using traditional risk factors for coronary heart disease to assess the risk of exercise is not very accurate. Therefore, based on evidence from relevant domestic and international studies, the consensus divides exercise-related cardiovascular risk into two strata: low-risk status and high-risk status.
Low-risk state: is a state in which exercisers have the same risk of cardiovascular events associated with exercise as healthy people of the same age and gender.
High-risk status: A state in which the absolute risk of exercise-related cardiovascular events is significantly higher than that of healthy people of the same age and gender due to a combination of multiple risk factors such as advanced age, definite cardiovascular disease, type 2 diabetes, or kidney disease, or participation in very risky and challenging sports (e.g., extreme mountain climbing, alpine skiing, triathlon, etc.).
The main variables used to stratify exercise-related risk are shown in Table 1. Low-risk states are those in which individuals have no core variables and at most one non-core variable; high-risk states are those in which individuals have at least one core variable or more than two non-core variables.
2. Cardiovascular risk assessment in the exercise population
Exercise-related cardiovascular risk assessment refers to the assessment of cardiovascular disease risk mainly in order to screen for the risk of pre-existing cardiovascular disease or cardiovascular events and to avoid the occurrence of exercise-related cardiovascular events in the population participating in exercise or during exercise.
The assessment of cardiovascular risk in the exercising population includes the assessment of four main aspects: cardiac structure, myocardial blood supply, arrhythmias and cardiac function. The diagnostic effectiveness of each test for cardiovascular disease is shown in Table 2.
Cardiac structure assessment.
Consensus points to the importance of assessing cardiac structure to screen for hypertrophic cardiomyopathy, as common causes of SCD in young adults include hypertrophic cardiomyopathy and high-risk congenital coronary artery malformations.
The main tests include echocardiography, electrocardiography, coronary CT angiography and cardiac magnetic resonance imaging (CMR), as well as invasive coronary angiography.
Myocardial blood supply assessment.
People over 40 years of age are prone to cardiac arrest or SCD during or after strenuous exercise, most commonly due to atherosclerotic heart disease. Risk assessment before and during exercise is particularly important in this population.
The main tests include the exercise plate test, cardiopulmonary exercise testing (CPET), stress echocardiography, stress myocardial perfusion imaging (rMPI), coronary CT angiography, and coronary angiography.
Consensus points out that CPET can be used to both screen for cardiovascular disease risk and individualize exercise instruction compared to other tests, making exercise safer and more scientific.
Arrhythmia assessment.
Previous studies have suggested that structural cardiac abnormalities are the primary cause of exercise-related sudden death in young adults, but more recent studies have suggested that the primary cause of SCD in young adults is sudden arrhythmia syndrome, making screening for relevant arrhythmias particularly important.
The main tests include resting ECG, ambulatory ECG, exercise ECG, CPET. in a few cases, electrophysiological examination and genetic screening are required.
Cardiac functional assessment.
Cardiac functional assessment mainly includes assessment at rest and under load, covering systolic and diastolic function and cardiac reserve capacity. It is important for high-risk groups.
The main tests include echocardiography, CPET, CMR, rMPI, and left ventriculography.
3 . Cardiovascular risk screening process in the exercise population
Low-risk population: no special assessment is needed, and primary assessment can be performed if desired.
High risk population: go directly to primary assessment. Those with a positive primary assessment and all high-risk populations are recommended to proceed to intermediate assessment for CPET to determine fitness status and further evaluation.
Positive intermediate assessment result: Exercise warning is given and further medical consultation and exercise instruction is required in a specialized medical facility.
Negative intermediate assessment: If there are no associated risk factors, exercise can be started directly, starting with low to moderate intensity and increasing gradually. If there is a history of associated heart disease then proceed to advanced assessment.
For those with no previous exercise habits, start with low to moderate intensity and gradually increase the amount of exercise, more slowly in the elderly. For those with previous exercise habits, continue with the current intensity.
Positive advanced assessment result: Exercise warning is given and further medical consultation and exercise advice is required in a professional medical institution.
Different individuals have different cardiac status, and individualized exercise training needs to be developed and guided according to the exerciser’s health status, physical ability, training response and exercise purpose.
Generally, in the 4-6 weeks at the beginning of the exercise program, the length of each training session is extended by 5-10 min every 1-2 weeks. when regular exercise is performed for at least 1 month, the frequency, intensity and duration can be gradually increased in the next 4-8 months to achieve the recommended individualized exercise training quality.
How to monitor cardiovascular health risk while exercising
For people exercising at home (low-moderate risk of cardiovascular disease): physicians can recommend appropriate wearable-type devices to monitor cardiovascular health risk; without monitoring devices, exercisers need to rely on symptoms, voluntary fatigue scores, and talking tests to monitor.
For example, moderate intensity physical activity is controlled for a voluntary fatigue score of 12 to 14, and a speaking test to the point of immediate breaking. If an individual develops symptoms such as chest pain and breath-holding before reaching moderate intensity, exercise is stopped and medical screening is performed.
For people at high risk of cardiovascular disease, it is still recommended to exercise at a medical facility until the risk status is downgraded, and the medical facility will have a full range of monitoring and professional staff.
What if an emergency occurs during exercise?
If an individual experiences discomfort during exercise, it is recommended that they stop exercising immediately and sit down to rest. If rest does not provide relief, it is necessary to consult a physician.
The most dangerous condition during exercise is SCD. In order to avoid the occurrence of SCD reduction, it is recommended that a symptom assessment be performed prior to each exercise session to identify early risks and thus prevention.
In the unfortunate event of SCD, the first aid process needs to be initiated immediately. Perform calls and calls for help while attempting CPR. Multiple studies have confirmed that bystander performance of CPR is the only factor that improves survival from out-of-hospital SCD.
Bystanders can identify the occurrence of ventricular fibrillation with an automated external defibrillator (AED) if the scene is equipped with one prior to the arrival of an EMS vehicle.
Ordinary defibrillators require qualified personnel to use them, while AEDs can be operated by non-medical personnel. It is recommended that AEDs be set up in all public places and that CPR training be provided to relevant personnel.
