A large number of patients who have had a heart attack die immediately or within four weeks after it. A new study has shown that physically active people have a much higher chance of surviving this period than those who lead a sedentary lifestyle. Scientific work published in the European Journal of Preventive Cardiology.
Physical activity and heart disease
Ischemic heart disease is the leading cause of death in the world. Therefore, its prevention is one of the main health priorities. Regular physical activity has a protective effect: it reduces the risk of disease and can slow its progression. It is known that its effect in reducing the risk of death is dose-dependent: it is higher if a person is engaged.
Physical activity is central to guidelines for the prevention of cardiovascular disease. At the same time, its mechanisms of action are not fully understood. It is now believed that the so-called ischemic preconditioning plays an important role. We are talking about the occurrence during exercise of short episodes of lack of blood in the heart muscle, followed by normalization of blood circulation. At this time, the heart trains to resist ischemia: the body begins to quickly produce substances that increase blood flow, resulting in the formation of additional vessels. In experiments, scientists have shown that physically active animals have smaller foci of myocardial infarction than passive ones.
Physical activity prevents instant death
Scientists from Denmark decided to find out how past physical activity protected against death in the acute phase of myocardial infarction: immediately and within 28 days. They analyzed data on 28 thousand people who died from myocardial infarction. The researchers grouped study participants based on how physically active they were in their spare time.
Within 28 days after a heart attack, almost 5 thousand people died, 62% of them died immediately. The more physically active study participants were, the more likely they were to live longer.
In people with moderate and high levels of physical activity, the risk of instantaneous death from myocardial infarction was lower by 33% and 45%, respectively, than those who led a sedentary lifestyle. On the twenty-eighth day, they had a 36% and 28% lower risk of death, respectively
«Almost 18% of patients with myocardial infarction died in the first 28 days, which underlines the severity of this disease . We found that physical activity in the past helps to survive immediately after a heart attack, and, as we see, this effect extends to 28 days,” said Dr. Kim Wadt Hansen (Kim Wadt Hansen) from the Bispebjerg Hospital in Copenhagen, co-author of the study.
According to the authors, their work shows that even a low level of physical activity reduces the risk of heart attack — however, this statement needs additional research.
It is noteworthy that the study supports the current physical activity standards presented in the European Guidelines for the Prevention of Cardiovascular Diseases. The document recommends 150-300 minutes of moderate or 75-150 minutes of vigorous physical activity per week.