The main cause of myocardial infarction is the obstruction of the coronary arteries.
What is myocardial infarction?
It is a pathology that is characterized by the death of a portion of the heart muscle that occurs when a coronary artery is completely blocked.
In the circumstances in which obstruction occurs the blood supply is suppressed. If the heart muscle lacks oxygen for too long, the tissue in that area dies and does not regenerate.
According to Joelmary Isabel Garcia, president of the Ischemic Heart Disease and Acute Cardiovascular Care section of the Society of Cardiology (SEC), this pathology manifests itself when people reach middle age and affects both men and women. “In women the disease manifests itself about ten years later than in men, so the myth that women are not affected by ischemic heart disease is a lie.” This is because the hormonal situation of the menstruating woman makes her more protected against the risk of suffering a myocardial infarction.
The myth that a heart attack does not affect women is a lie.
The results of the Recalcar registry, a report prepared by the SEC with patient data based on discharge reports from hospitals throughout Spain, indicate that there are currently about 52,000 hospitalized heart attacks per year. This figure has dropped slightly in recent years and is currently stabilized.
“We must bear in mind that there are heart attack patients who die before reaching the hospital, so we find a significant percentage of patients who are not counted within these 52,000 cases,” Lidón clarifies.
The main cause of myocardial infarction is the obstruction of the coronary arteries. For the heart to function properly, blood must circulate through the coronary arteries. However, these arteries can narrow, making circulation difficult.
If the heart is overstressed, disorders can develop and form a clot, which, in turn, can plug a semi-blocked artery. This blockage cuts off the blood supply to the heart muscle fibers. When they stop receiving blood, these fibers die irreversibly. A myocardial infarction occurs when a blood clot (coronary thrombosis) blocks a narrowed artery. Usually, a heart attack does not happen suddenly. It can be caused by atherosclerosis, a prolonged process that narrows the coronary vessels.
There are factors that can accelerate the deterioration of the arteries and cause them to clog, as Lidón points out, who highlights tobacco, cholesterol, diabetes and hypertension as some of the cardiovascular risk factors that force the heart to function in worse conditions.
At present, myocardial infarctions in young people have increased in Spain and, according to Lidón, this increase is linked to drug use. “We have verified that the majority of heart attacks that occur at young ages are directly related to cocaine use. In addition, they do not have to be large consumptions, “he says. “When we see a heart attack under 40 years of age, we always look to see if there is cocaine in the body.”
Assess your symptoms
The classic description of a heart attack is an oppressive pain in the center of the chest radiating to the arms (especially the left), neck and back. “This is a subjective sensation of the patient. In some the pain sometimes transforms into oppression; in others, in discomfort ”, says the specialist. “Due to these subjective differences, health workers have the obligation that, before any discomfort that occurs from the waist up and that is affecting the patient, perform an electrocardiogram that will reveal if the heart is suffering.”
The usual symptoms are:
Intense and prolonged chest pain, which is perceived as intense pressure and which can extend to the arms and shoulders (especially the left), back and even teeth and jaw. The pain is described as a huge fist twisting the heart. It is similar to angina, but longer and does not stop even if a nitroglycerin tablet is applied under the tongue.
- Dizziness in ten percent of the cases.
- Others: Nausea, vomiting and fainting may appear.
The risk of having a heart attack can be avoided by following some healthy living guidelines:
Give up smoking.
Eat a balanced diet rich in fruits, vegetables, legumes and cereals. “It has been shown that the Mediterranean diet is the most effective in preventing both the occurrence of heart attacks and recurrences,” adds Lidón.
Do aerobic physical exercise.
The president of the SEC’s Ischemic Heart Disease and Acute Cardiovascular Care section advises that the best exercises for the heart are walking, cycling or swimming. “Walking 30 minutes a day in the morning and in the afternoon is a guarantee of success for heart health and would help control cardiovascular risk factors.
Avoid alcoholic beverages.
The simplest, most obvious, and most effective test during pain to diagnose an acute myocardial infarction is the electrocardiogram. However, if, for example, the patient has an attack of angina and visits the doctor between pain and pain, the electrocardiogram may be normal. In these circumstances, Lidón specifies that specialists can perform other tests, such as stress tests, to see if when they put pressure on the heart there are alterations in the electrocardiogram.
The main diagnostic tests that are performed are:
It is the fundamental test to diagnose acute infarction that, in addition, allows to analyze its evolution. During the electrocardiogram, the patient is monitored at all times.
The test reveals a graphical representation of the electrical forces working on the heart. During the heart’s pump-and-fill cycle, a pattern of changing electrical pulses accurately reflects the action of the heart. This test is painless and is usually done with the patient stretched out and calm, except when done during a stress test.
The electrocardiogram only detects abnormalities at the time pain occurs. Later, it is used only to confirm or rule out whether there has been damage to the heart.
Through a blood test, the increased serum activity of certain enzymes that are released into the bloodstream due to necrosis that occurs during the heart attack can be detected.
To give this information with certainty, the enzymatic values are taken by series during the first three days. The maximum values of these enzymes show a discrete correlation with the extent of necrosis, although other factors that influence their degree of activity must also be taken into account. In short, it is a complex calculation of values.
On the other hand, interesting prognostic parameters are also obtained, such as cholesterol level, glucose levels (diabetes increases the risk of heart disease) and thyroid hormones (an overactive thyroid can cause cardiac abnormalities).
It can be done on a stationary bike or a treadmill. In the test, the specialist will place electrodes on the patient’s body, to continuously record the electrocardiogram, and a tension cuff.
As the patient pedals or walks on the treadmill, the physician supervising the test will observe changes in blood pressure, pulse, and EKG tracing. The test is completed in half an hour and is abandoned if changes suggestive of disease appear in the observed parameters or if the patient does not tolerate it physically, due to exhaustion or difficulty in breathing.
These studies are associated with the stress test and consist of the analysis of the heart with isotopes. During exercise on the bicycle or on the treadmill, a small dose of radioactive isotope is injected into the vein. Meanwhile, a special device records a series of images of the isotope’s locations in the heart (the dark areas indicate the parts where the blood flow is not reaching well).
The downside of this test is that the isotopes do not give information about the particular blocked artery.
There are different modalities of isotopic examination: scintigraphy, which increases the sensitivity and specificity of the stress test in men; ventriculography, which allows the rapid determination of ventricular volumes and the detection of areas of abnormal mobility due to ischemia, very useful for prognosis; and scintigraphy, which can detect defects in the expansion or contraction of the heart wall, a sign that the arteries do not transport enough oxygenated blood to the area.
Cardiac catheterization and coronary angiography
It is the most appropriate technique to determine the possible presence and extent of ischemic heart disease.
It allows determining the location and degree of obstruction of coronary artery lesions that may have occurred. It cannot be performed when the patient has coagulation disorders, heart failure, or ventricular dysfunction.
As soon as the patient suspects that he has some of the symptoms already described, he should immediately notify the emergency services and then they can take an aspirin (it has an antiplatelet effect that inhibits the formation of clots in the arteries). “One of the problems derived from a heart attack is that a malignant arrhythmia occurs and the patient dies,” explains Lidón. “If the health service is in front, the consequences may be less because they can activate the action protocol in the event of a heart attack.”
According to the specialist, the electrocardiogram.
It will mark the type of treatment. Thus, if an ST elevation infarction occurs, doctors will activate all the mechanisms to try to open that artery as soon as possible. “In the event that the infarction does not have ST elevation, the doctor will have to study the coronary anatomy, the pumping capacity of the heart, decide whether to perform a coronary angiography and act accordingly, either through the same catheter or indicating a surgery ”, says Lidón.
The specialist insists that whether the specialists perform percutaneous coronary intervention or if they perform surgery, it is necessary for the patient to undergo medical treatment for life. “These treatments are indicated to facilitate healing, reduce the work of the heart so that it can function properly and prevent new heart attacks from occurring”, she specifies. “Our goal is to control all cardiovascular risk factors to prevent coronary disease from progressing and, if it does progress, to do so as slowly as possible.
In the hospital, patients can receive different types of treatments:
It is usually the first measure that doctors take in the hospital and in the ambulance itself.
In situations where chest pain persists, morphine or similar drugs are given to relieve it.
They prevent the stimulating effect of adrenaline on the heart. In this way, the heartbeat is slower and has less force, so the muscle needs less oxygen.
They dissolve clots that prevent blood from flowing. To be effective, they must be administered within an hour after the onset of symptoms and up to approximately 4.5 hours.
These types of drugs, such as aspirin, prevent platelet aggregation in the formation of thrombi.
They are calcium channel blockers. They prevent the entry of calcium into myocardial cells. This reduces the tendency of the coronary arteries to narrow and makes it possible for the heart to work less, thus reducing its oxygen needs. They also lower blood pressure.
They decrease the work of the heart. In the acute phase of a heart attack, they are often used venously and / or sublingually.
Digital. They stimulate the heart to pump blood.
The procedure involves selecting a section of a vein or artery from another part of the body to join the coronary artery above and below the blocked area. This creates a new route or bridge through which blood can flow to the heart muscle.
Percutaneous coronary intervention.
The goal is to open the lumen of the blocked artery. The specialist will determine the infarcted vessel with an initial angiography and subsequently perform a balloon angioplasty of the thrombosed segment, being able to implant a stent. Sometimes they can remove the thrombus with a suction catheter.
Other information Prognosis of the disease
The improvement in the disease is contingent on obesity, which also has a negative impact on others, such as high blood pressure and diabetes.
It is one of the most important problems that exist today. The increase in incidence is already observed both in child age groups, as well as in young people and adults. This pathology increases blood pressure, diabetes, cholesterol levels and, by itself, is a risk factor. Despite the fact that with all the treatments we are improving the prognosis of the life of the heart attack, factors such as diabetes cause the heart attack to occur at an earlier age ”, points out Lidón.
The specialist specified the prognosis of the disease.
is that knowledge about it is increasing although it continues to kill without doctors being able to do anything in many cases. “It has lost some of the extreme gravity that it had before. However, we have a challenge: there is still a high percentage of patients who die before reaching the hospital and this percentage will increase with risk factors that are not controlled ”.