Myocardial infarction: symptoms, treatment, prognosis

Overview

In heart attacks, there is a closure of one or more coronary arteries, which are responsible for supplying the heart muscle with blood and oxygen. Without this important supply basis, parts of the heart muscle tissue die within a very short time, which in the worst case can lead to total heart failure with circulatory failure and death.

A heart attack does not come from nothing

Although myocardial infarction is an acute disease that can present with sudden onset of severe discomfort such as chest, back and upper abdominal pain, nausea, vomiting, cold sweating and anxiety, it is the result of many years of degenerative changes in the coronary arteries. These changes on the vessel walls (atherosclerosis) are caused by years of exposure to certain risk factors such as smoking, obesity, stress, diabetes mellitus, hypertension and an increase in blood lipid levels.

Arteriosclerotic altered vessels are far more prone to injury. Vascular wall injuries in turn can activate platelets that form a clot to occlude the injured site. This actually physiological process in the coronary arteries can lead to a sudden closure and thus to an infarct.

Fast action is required

A heart attack counts every minute. Since the heart tissue can survive only a few hours under reduced or missing oxygen supply and is not capable of regeneration, in case of suspected heart attack, immediate contact with an emergency physician is always essential. After diagnosis, this person immediately initiates further treatment in a suitable hospital, which usually has to have a cardiac catheterization laboratory in Germany.

After the reopening of the closed vessel in the acute hospital, a short inpatient hospital stay, during which early rehabilitation is already started, and a stay in a qualified rehabilitation clinic usually follow.

But even after completion of the rehab therapy of heart attack is far from complete. As a rule, a lifetime of medication must be taken to prevent further events. Furthermore, a change in lifestyle should be heeded, focusing on a healthy diet, sufficient exercise in the fresh air, the consistent smoking waiver and a reduction of physical and psychological stress.

How does a heart attack develop?

In most cases, a heart attack is the result of many years of degenerative changes in the coronary arteries (arteriosclerosis). In the process, lime or cholesterol builds up on the vessel walls over years or decades, forming plaques there. On the one hand, these plaques lead to an increasing narrowing of the vessel diameter and, on the other hand, to an instability and brittleness of the vessel wall.

Without blood, no oxygen

Due to the pressure and shear forces of the passing blood, plaques can rupture or detach from the vessel wall. When this happens, platelets are activated, which have the task of providing rapid wound closure and forming clots (thrombi) on injured vessels to stop bleeding. In the coronary arteries, this can have fatal consequences. If the clot is particularly large, it can also clog a vessel completely and cut off the bottleneck downstream parts of the heart muscle from the blood circulation. If no blood reaches the heart muscle tissue, it leads to an acute lack of oxygen, which leads to the death of the heart muscle tissue - a heart attack is the result.

The supply of the heart with blood and the oxygen contained therein is mainly via three large coronary arteries (coronary artery), which branch out to ever smaller branches in the direction of the heart. Depending on where a vessel is affected by the occlusion, smaller or larger infarcts occur. Very large infarcts can lead directly to death, while small infarcts can also go unnoticed.

A scarred heart beats worse

If cardiac muscle tissue dies of acute hypoxia, it is gradually replaced by non-functional scar tissue, leading to a decrease in cardiac output.In very large or multiple small scar areas, the heart may be so severely impaired in its function that heart failure (heart failure) arises, which is not curable and can often lead to further complications such as arrhythmia, dizziness and water retention in the legs or lungs.

Causes and risk factors

In most cases, the mechanism described above is the cause of a heart attack. An atherosclerotic plaque separates from the unstable vessel wall or ruptures and is occupied by a clot that results in a complete occlusion of the vessel.

Rarely: embolism and coronary spasm

In rarer cases, however, it also happens that a blood clot from another location, for example, from the legs or the heart itself, is carried with the blood stream in the coronary artery and closes a healthy vessel. In such cases it is spoken of an embolism.

Also rare is the coronary spasm, a spasm of a coronary artery, which leads to a temporary interruption of blood flow, but in most cases after a short time (seconds to a few minutes) spontaneously dissolves again.

As a rule, a heart attack is the result of many years of vascular changes that can be caused by factors affecting the vessel walls. Some of these risk factors are influenceable and therefore preventable. Others are not, because they have a genetic component and are hereditary.

Factor lifestyle

The most important risk factors that can be significantly reduced by a healthy lifestyle and by a drug therapy are:

  • Smoke
  • Overweight and lack of exercise
  • high-fat and carbohydrate diet
  • mental or physical stress
  • high blood pressure
  • elevated blood lipid levels (especially cholesterol and LDL)
  • high blood sugar levels (diabetes mellitus)

What is not in your hands

Hereditary risk factors that can not be influenced include:

  • Age (men over 55 years, women over 65 years)
  • male gender
  • First-degree relatives (parents, siblings) who have had a heart attack before the age of 60

You'll find more about it here:
Important questions and answers about the risk

symptoms

An acute myocardial infarction usually manifests itself in very sudden onset of discomfort. These occur, unlike one would expect, usually not during great physical or mental tension, but heaped in phases of rest, especially in the early morning hours.

Pain like never before

The main symptom is chest pain, which is located behind the sternum in the heart and is often described as the strongest pain ever felt. Often there is also a pain in the left, rarely in the right arm, in the upper abdomen, the back or in the jaw angle.

Concomitants that are common in a heart attack are:

  • cold sweat
  • Nausea and vomiting
  • difficulty in breathing
  • paleness
  • unrest
  • agony

A heart attack can have many faces

But not every heart attack presents itself through clear complaints. Especially in women, an acute coronary occlusion can only be shown by rather atypical symptoms such as epigastric pain, nausea, vomiting and dizziness.

In a long-standing, poorly controlled diabetes mellitus, an infarction can even go without any pain symptoms. These so-called "silent infarcts" can be explained by a secondary disease of diabetes: the so-called diabetic neuropathy, which makes nerve endings less sensitive to pain, temperature and vibration.

Since there is in some cases no sure sign, whether actually an infarction has taken place or not - call in case of doubt always the ambulance or the fire department. Because: "time is muscle." Only when the coronary vessel is reopened in time, the heart muscle tissue has a chance to survive and fully regenerate. In case of doubt, do not look for your family doctor, but choose the 112. This way, you can avoid costly waiting time and land directly in a suitable clinic, which can also provide you with interventional support in case of emergency.

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Worth knowing about the symptoms

diagnosis

To diagnose a heart attack, there is usually a very small window of opportunity. Although old infarcts can be detected for a long time with suitable diagnostic instruments, the possibility for a sufficient therapy decreases every hour. The later the treatment is started, the less heart muscle tissue can be obtained.

The right questions

To diagnose, your attending physician, who is usually an emergency physician or, more rarely, your general practitioner, will ask you specific questions to assess the likelihood of having a heart attack.

Important questions include:

  • how old are you
  • whether the pain in the heart area is dependent on physical exertion
  • whether a vascular disease is already known
  • whether you yourself suspect heart disease
  • whether the pain is aggravated by pressure on the chest

ECG and laboratory create clarity

Subsequently, blood pressure and pulse are measured. In addition, the heart and lungs are monitored to detect heart sounds and to assess the circulatory situation.

Immediately following the physical examination is the recording of an electrocardiogram (ECG). The electric cardiac currents are measured with the help of electrodes attached to the chest. These show in the healthy state a very characteristic pattern that changes during a heart attack in a typical manner and thus provides clues on the age, size and localization of the infarcted area.

Another important diagnostic criterion can be determined by taking a blood sample. When cardiac muscle tissue dies, certain proteins (enzymes and proteins) are released into the blood, which are normally absent there. These include, among others, the heart muscle-specific troponins T and I as well as creatine kinase (CK-MB). Above all, troponin rises early after an infarction in the blood, reaches its peak after about 12 hours and can be detected several days after the event. The detection of troponin in the blood is practically proof for the diagnosis of myocardial infarction, even if no infarct typical changes in the ECG can be found.

With the heart catheter to the place of the action

If indications for a heart attack can be found in ECG and blood, a coronary catheterization (coronary angiography) must be performed as soon as possible. This allows the radiographic representation of the coronary arteries and provides clues about where the infarction is located exactly how big he is and what treatment should be chosen to save as much heart muscle tissue. Under certain circumstances, the vessel can be reopened during the examination.

More on this topic can be found here:
Questions about diagnostics

treatment

The top priority of heart attack therapy is that it be initiated as soon as possible. Because every minute can do more irreparable damage and lead to increasingly longer rehabilitation phases. Therefore, if you have the slightest suspicion that an infarct has occurred in you or a person in your area, immediately call the ambulance.

1. In front of the clinic

The time span before reaching a suitable hospital is often the decisive prognostic factor for the entire further course as well as the therapy of the heart attack. Once you have called the ambulance, take care of the helpless person. Even if you have little experience in the field of medicine, there are a few things you can do:

  • Address the affected person.
  • Check if she is breathing.
  • Help with a comfortable storage, preferably with a slightly raised upper body.
  • Open tight garments such as a tie, jacket or shirt.
  • Stay calm, and also try to exert calming influence.

It depends on the first responders on site

If it comes to a cardiovascular standstill (the affected person is then no longer responsive, it can feel neither a pulse nor a breathing), you begin without delay with the chest compressions. If you do not remember the exact procedure, kneel next to the affected person, place your hands on top of each other and place the lower part of your hand in the middle of the sternum. Stretch your arms, keep your back straight and perform chest compressions in this position.

These should be best:

  • 5-6 cm deep (about one third of the thorax width) and
  • at a frequency of 100-120 times per minute.

As soon as the ambulance arrives, he will take the lead and give you instructions on how to proceed. Furthermore, the doctor organizes the transport to a suitable clinic, which should not be too far away, but should nevertheless be equipped with a cardiac catheterization laboratory.

2. acute care in the hospital

When diagnosing a heart attack, hospital admission is always essential. As a rule, home or emergency doctor decide on the basis of distance and equipment of the clinic, which house is the most suitable.

Anyway, the blood has to flow again

First of all, there is only one goal in the clinic: to reopen the closed coronary vessel and to save as much cardiac muscle tissue as possible. Depending on how fast the clinic can be reached and how big the infarcted area is, there are two different therapeutic approaches:

  • Primary Percutaneous Coronary Intervention (PCI) is the drug of first choice.
  • Alternatively, a lysis therapy may be performed.

In the case of PCI, a stent is catheter-guided over the groin to be advanced into the coronary vessels and placed at the constriction there. The catheter is usually equipped with a balloon that initially dilates the constriction of the coronary vessel before a stent is implanted.

If PCI is not possible, a lysis therapy must be carried out. Certain drugs are administered via a vein (usually the arm), which should lead to a dissolution of the blood clot in the coronary artery.

Which method is used ultimately determines the time factor. Can a cardiac catheterization laboratory be reached 90 minutes after the arrival of the emergency physician?If the complaint has not returned for more than 12 hours, a PCI will be executed. In all other cases, the lysis therapy is used.

Intensive care unit, normal ward, rehab

Following a successful PCI or lysis therapy, very thorough and close monitoring is necessary. For this reason, a stay of several days in intensive care (ITS) is necessary. Only there are the appropriate devices to monitor blood pressure, heart rate and oxygen saturation and to detect and treat complications such as cardiac arrhythmia or even shock at an early stage.

As a rule, the ITS relocates to the internal medical standard ward, where early rehabilitation can already begin. Furthermore, the oral medication is discontinued, which you have to continue independently until the end of your life. Overall, the hospital stay takes several days to weeks - depending on the severity of the infarction.

After the inpatient phase in an acute hospital, a rehabilitation treatment usually lasts for two to six weeks. This pursues several goals. On the one hand, your physical capacity is slowly being rebuilt and, on the other hand, it is about preventing a renewed infarct. As a rule, this only succeeds through a change in lifestyle, through consistent smoking abstinence, a change in diet and more exercise in the fresh air.

What usually easily manage during rehab, but is often difficult to implement in everyday life, as old habits can creep in quickly and got the good intentions of improving body image also easily forgotten.

You can read more about the treatment here:
Everything important for emergency therapy

3. After the infarction

After discharge from the hospital and after completion of the rehabilitation treatment, the therapy of myocardial infarction is not completed. On the contrary - from now on a phase in which you have to do a lot for your health, to avoid sequelae of the heart attack such as heart failure, to regain your old form, but also to avoid renewed heart events.

The treatment of the recent infarction is multimodal and relies on various pillars. These include:

  • medical therapy
  • Reduction of existing risk factors
  • Prevention measures of further infarction events

a) Drug therapy

Post-treatment of myocardial infarction always includes drug therapy. At the beginning of the treatment, the selected classes of medication are based on whether stenting or lysis therapy has primarily led to the elimination of the thrombus and which type of stent has been used. Furthermore, the drugs are adapted to the cardiac output and then selected to improve survival after infarction.

blood thinner

Probably the most important class of drugs for the treatment of heart attack are the blood thinners. They ensure that no new thrombi form in the body, and especially in the coronary arteries, by preventing the platelets from networking (coagulating).

After an infarction, you will be taking acetylsalicylic acid, short ASS (Aspirin®Godamed®, Heart ASS®, Togal-ASS®, ASS-rathiopharm®) therefore have to take for your entire life. Shortly after inserting the stent, you also get a second, blood-thinning drug. The reason for this is that the stent promotes the formation of thrombi and therefore a double anticoagulant must be used (dual platelet aggregation inhibition).

Depending on which stent has been used, the combination of ASA and another preparation, such as clopidogrel (Plavix®, Isocover®), Prasugrel (Efient®) or ticagrelor (Brilique®, Possia®) are taken up to 12 months. Thereafter, the switch to the sole administration of ASA in low dosage (100 mg a day).

A disadvantage of the blood thinners is that they can lead to bleeding and more often associated with stomach problems such as gastric ulcers.

fat reducers

The substance class of statins such as atorvastatin (Sortis®, Atorvalan®), Pravastatin (Pravalip®, Mevalotin®) or simvastatin (Zocor®) is used regularly after a heart attack. The background is that statins not only lower blood lipid levels, in particular cholesterol and LDL levels, but also contribute to the stabilization of plaques and thus prevent the development of recurrent heart attacks.

Statins have the disadvantage that they are not always well tolerated and can often lead to general complaints such as fatigue, tiredness and muscle and limb pain.

ACE inhibitors

ACE inhibitors such as Ramipril (Delix®, Vasotope®) or enalapril (Xabef®) are now standard in many clinics after a heart attack administered. They have a preventive effect on existing heart failure and promote the regeneration of the heart muscle tissue.

Since ACE inhibitors often cause a tormenting cough, a switch to AT1 blocker may be necessary. This newer substance class has comparable effects to ACE inhibitors, but with a better side effect profile.

beta blocker

Beta-blockers such as metoprolol (Beloc®, Beloc ZOK®, Lopresor®) Nebivolol (Nebilet®) and bisoprolol (bisoprolol®, Concor®) are used only in special cases. Namely, when, following the heart attack, a very irregular and rapid heart rhythm develops, or when a heart failure occurs.

Since beta blockers do not offer a safe survival advantage, their use is always an individual decision.

b) reduction of existing risk factors

In most cases, myocardial infarction is a product of unfavorable factors influencing the body or the cardiovascular system. If these risk factors are recognized for the first time in the course of myocardial infarction, medication must be intervened in many cases in order to prevent further events. The biggest risk factors are an elevated blood pressure and an existing diabetes.

Regular control of blood pressure and sugar

In hypertension, various drugs are used, which inter alia with those of the heart attack therapy cover. As a rule, values ​​below 140 / 90mmHg are sought after an infarct, which should be controlled by home measurements at home. The dose of medicinal hypertension therapy can be reduced in many cases by regular exercise and low-salt diet.

In diabetes mellitus (in most cases it is a diabetes mellitus type 2) must be paid strictly to the blood sugar. Again, home self-measurements are necessary to regularly control the mirrors. According to the German guidelines, a fasting blood sugar value should not exceed the limit of 110 mg / dl and the long-term blood glucose value (HbA1c) should be about 6.5-7%. As with the treatment of high blood pressure, you can also contribute to your heart health and the regulation of your blood sugar level through exercise and healthy nutrition.

c) prevention measures of further infarction events

Probably the most important and often the most difficult preventable measure for further infarction events is the lifestyle change. It is often about saying goodbye to old habits of several areas of life and adopt a healthier lifestyle. This is often difficult.

But what many do not realize is that there are numerous offers that help to develop and successfully apply strategies and motivation for changing one's life. Ask your doctor about it and take advantage of the offers!

Smoking: risk factor number 1

Anyone who quits smoking can reduce the risk of having a heart attack by 30-50%. Since smoking is often not just vice or a bad habit, but an addictive disease, many people find it very difficult to quit. The recidivism rate is enormous.

Still, try it. But not alone. Get help from your family doctor and get informed about the numerous smoking cessation programs.

Healthy and delicious: the right diet

Every child knows that the best diet is healthy and balanced. But what exactly is meant by that is not clear to many people.

Especially after a heart attack or for the prevention of cardiovascular diseases, the Mediterranean cuisine is recommended. This includes plenty of fresh vegetables and fruits, vegetable fats and fish once or twice a week. The consumption of animal fats, meat, sugar and hidden salts should be avoided or significantly reduced. Hiding salts are found mainly in finished products such as frozen pizza, instant soups or microwave dishes.

In order to learn the Mediterranean cuisine and to develop your own recipe ideas, participate in a cooking class or a nutritional consultation.

Get your heart on the move!

Finally, the heart should be kept fit. This works best with moderate training. Recommended are 30-60 minutes of daily endurance training in the form of walking, swimming or cycling. There is no need for high-performance sports, even extended walks in the fresh air are good for heart health.

Especially those who come fresh from rehab or do not want to do sports alone, can also join a dedicated heart sport group for this purpose.

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Frequently asked questions about aftercare

forecast

The prognosis of a heart attack is difficult to predict. It correlates not only with the size of the infarct area and the severity of the symptoms, but also with their own behavior after the infarction. Who consistently changes his lifestyle, moves more, no longer smokes and feeds healthier, has a much better prognosis than the one who continues after the infarction as before.

As a small suggestion for you:
10 tips after heart attack

 

Author: Lisa Wunsch

sources

G. Herold: Internal Medicine, Herold Verlag, 2017-12-17.

H. Renz-Polster, S. Krautzig: Basic textbook Internal Medicine, Urban & Fischer, 2012.

S.K.G. Maier et al .: Recommendation on the organization of heart attack networks, http://leitlinien.dgk.org/files/2014_Empfehlung_Herzinfarktnetzwerke_Druck.pdf, last accessed on 27.12.2017.

Borja Ibanez et.al: Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation, https://academic.oup.com/eurheartj/advance-article/doi/10.1093/eurheartj/ehx393/4095042, last accessed on 27.12. 2017th

T. Herdegen: Short Textbook Pharmacology and Toxicology, Thieme Verlag, 2013.