A heart attack is caused by coronary heart disease. It is an emergency which requires correct, urgent action. The more quickly a patient suffering an infarction receives the correct treatment, the better their prognosis will be.

What is a heart attack?

A heart attack (also known as myocardial infarction) occurs when at least one coronary artery closes completely. A blood clot which attaches itself to an arteriosclerotic constriction is generally responsible for the obstruction. As a result, a part of the heart muscle no longer receives oxygen. If this circulatory disorder is not treated immediately, this part of the heart muscle quickly dies. 

Scar tissue also forms in the heart muscle after a heart attack. This can cause cardiac arrhythmias or cardiac insufficiency.


A heart attack is usually caused by arteriosclerosis. The main risk factors for the occurrence of arteriosclerosis are:

If an already calcified coronary artery is completely closed by a blood clot, this causes a myocardial infarction.  

Symptoms of a heart attack

Heart attack patients often suffer from angina pectoris with temporary circulatory disorders of the heart before a heart attack, the cause of which is calcification (arteriosclerosis) of the coronary arteries.

However, unlike angina pectoris, the symptoms of a heart attack are generally much stronger: 

  • Severe chest pain or a feeling of tightness in the chest. This is accompanied by shortness of breath, nausea, sweating and fear of death. Doctors also call these clinical symptoms acute coronary syndrome.  
  • Milder pain which does not improve when a patient keeps still and lasts longer than 15 minutes. The pain also often radiates into the neck, the shoulders and the arms.


If you suspect that someone is having a myocardial infarction, they must be immediately admitted to hospital. The doctor can quickly make the diagnosis with an ECG examination and by determining the troponin level in the blood. Troponin is a substance which occurs if the cells of the heart muscle are damaged. If a patient has an infarction, increased troponin levels will already be detectable in the blood soon after the event.

You can find out how to recognise a heart attack and what you can do at Heart attack: emergency first aid.


It is vital that blood flow is restored to the heart muscle quickly after a diagnosis has been made. There are various options available. Depending on the situation, the blood clot responsible for the infarction can be dissolved with medication (thrombolysis), or the blocked blood vessel can be opened surgically.

Find out more about the surgical treatment methods using balloon dilatation, stent or bypass surgery in the section about Coronary arteries: operations and procedures.

After a myocardial infarction, existing risk factors usually require life-long treatment to prevent further attacks. Depending on the constellation, these include antihypertensives, cholesterol-reducing medication and blood thinners.

Emergency first aid

Cardiovascular diseases are the leading cause of death in Switzerland. In the event of a heart attack, swift action must be taken to increase the chances of survival and to minimise permanent damage to the heart. But what are the symptoms of a heart attack and how should a person react?

What are the symptoms?

How do I recognise a heart attack? 

A heart attack has the following symptoms:

  • Chest pain / feeling of tightness in the chest
  • Sweating
  • Nausea, vomiting, indigestion
  • Shortness of breath
  • Anxiety and fatigue, dizziness

The pain experienced during a heart attack is often severe to unbearable and can radiate into the shoulders, arms, neck, upper abdominal, lower jaw and the back.

What should you do?

What should I do when someone suffers a heart attack? 

If you think a person is having a heart attack, do the following:

  • Call 144 to report the emergency
  • Explain that you think the person is having a heart attack
  • Give the name, address, and age of the patient
  • Position the patient on a hard surface with their upper body slightly elevated
  • Open tight clothes, ties or bras
  • Ask passers-by to help flag down the ambulance so that you can stay with the patient and help keep them calm

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