Myocardial infarctions are the leading cause of death worldwide. This is a type of coronary accident related to lifestyle; In particular, the appearance of heart attacks is directly influenced by sustained stress and unhealthy habits.
In this article we will analyze the mechanisms by which Stress can lead to heart attacks For this it is necessary that we first stop at the definition of these two concepts.
We can define stress as a set of physiological responses that occur to the appearance of stimuli or situations that the body perceives as threatening or demanding
These body reactions are nonspecific and stereotyped; This means that they do not depend on a specific type of environmental stimulation and that they are very similar regardless of the causes that cause them.
Physiological stress responses depend on the activation of the hypothalamic-pituitary-adrenal axis and the autonomic nervous system Short-term effects consist of an increase in heart rate and stored energy consumption, as well as other signs of physical activation.
Physiologist Hans Selye described three phases of stress in his General Adaptation Syndrome model. During the alarm phase the body recognizes the stressor and mobilizes to cope with it; If the stress still persists, we move on to the resistance phase, in which activation decreases a little in order to be maintained in the long term.
When the organism has consumed its resources The third phase appears, called “exhaustion” and characterized by the reappearance of the intense symptoms typical of the alarm phase. Although the advanced phases of the stress response harm the body, the alterations usually disappear after a period of rest during which the person generates new energy reserves.
When stress is sustained on a sustained basis, it causes what we know as stress syndrome, consisting of the appearance of peptic ulcer, an increase in the size of the adrenal gland and a decrease in the thymus. These alterations are related to massive secretion of glucocorticoids and suppression of the immune response which facilitates the development of diseases.
Today’s increasingly stressful lifestyle has promoted a clear increase in the prevalence of blood circulation disorders, such as heart attacks and hypertension. Having high blood pressure increases the probability of atherosclerotic plaques accumulating, and therefore of cardiovascular accidents.
There are also many psychological symptoms that can be influenced by stress: anxiety, irritability, apathy, sadness, emotional instability… Among the disorders caused by stress anxiety and depression stand out which, like cardiovascular disorders, are considered lifestyle diseases.
Definition of heart attack
Heart attacks are the main cause of death worldwide, according to the World Health Organization, and their frequency continues to grow; While in 1990 they explained 12% of deaths, in 2013 this figure was close to 17%.
Infarction consists of the death (or necrosis) of part of the tissue of an organ. Necrosis generally occurs as consequence of the obstruction of the artery that supplies it
When necrotic tissue is found in the heart muscles we speak of a myocardial infarction. Heart attacks can also occur in other organs; In addition to the heart, the most common are the brain, kidneys and intestine.
If the accident takes place in the kidneys we speak of renal infarction, while if they occur in the intestine the correct term is “mesenteric intestinal infarction”. Cerebral infarctions are known as “cerebrovascular accidents.” or “brain vascular accidents”.
Arterial obstruction is usually due to the accumulation of atheroma plaques (or atherosclerosis) but it can also be a consequence of hernias, the presence of tumors or deformation of the organ.
Among the most relevant factors that predispose to the appearance of heart attacks are tobacco and alcohol consumption, obesity, sedentary lifestyle , diabetes and high cholesterol levels. They also occur more frequently in men, in people over 40 years of age and in those with a family history of cardiovascular disorders.
How does stress cause heart attacks?
The appearance of heart attacks as a result of stress is due to the conjunction of a series of interrelated causal mechanisms. Specifically, scientific research has linked heart attacks to increased cortisol levels and hyperreactivity of the amygdala.
Cortisol is a steroid hormone which is produced in the adrenal gland and is released in response to stressful conditions. Although it is essential for the body to consume energy, excessive and continued secretion of cortisol can inflame the arteries, narrowing them and making them easier to block.
The amygdalae are two brain structures that are located in the temporal lobes and are involved in the learning emotional responses , including those of fear, anxiety and stress. When stress levels are high for much of the time, neurons in the amygdala learn through classical conditioning to trigger stress responses to stimuli that do not actually pose a threat.
Therefore, continued stress in itself negatively affects the cardiovascular system, but it also facilitates the amygdala associates the fear response with harmless stimuli In this way, a vicious circle occurs in which stress causes more stress, increasing the risk of heart attacks and other circulatory problems.
However, the continued practice of physical and cognitive relaxation exercises can help the body stop issuing stress responses at inappropriate times. Scientific research particularly supports progressive muscle relaxation procedures and slow, deep breathing.
