Heart attack

A myocardial infarction (heart attack) happens when one of the coronary arteries is suddenly blocked - leading to the death of part of the heart muscle. Myocardial infarction is more common in older people, and always constitutes a medical emergency. Prompt treatment may be able to limit the extent of the damage caused to the heart.

What is a heart attack?

The term heart attack - or myocardial infarction - refers to a sudden interruption in the blood supply to the heart, leading to the death of heart muscle tissue. Usually, a heart attack is the direct result of a blood clot blocking an already narrowed coronary artery - preventing the muscle cells from receiving a sufficient amount of oxygen. Most heart attacks are caused by coronary heart disease.

Acute myocardial infarction is often life-threatening, and is always a medical emergency. A heart attack can often cause dangerous arrhythmias, and approximately a third of patients will die before the emergency services have been notified.

According to WHO (World Health Organization) criteria, acute myocardial infarction is diagnosed if 2 of the following 3 criteria are satisfied:

  • Typical angina pectoris (crushing chest pain)
  • Increased cardiac enzymes following pain symptoms
  • Specific ECG changes

What are the main symptoms?

The symptoms of a heart attack can vary depending on the patient's gender and the location of the heart attack (e.g. anterior wall or posterior wall myocardial infarction). Although chest pain with pain radiating to the arms is often referred to as the cardinal symptom of a heart attack, it can be completely absent - particularly in women. Furthermore, some heart attacks may only produce minor symptoms or none at all ("silent" heart attacks).

In many patients, however, heart attack is characterized by dramatic symptom presentation. Many heart attacks occur in the early hours of the morning and involve the following symptoms:

 

What are possible causes?

As with coronary heart disease, a heart attack is usually associated with a hardening of the arteries (atherosclerosis) near/around the heart. In many cases, an acute heart attack occurs when one of the narrowed arteries is blocked as a result of a blood clot.
Atherosclerosis of the coronary arteries develops over many years and is associated with a number of specific risk factors. These include: 

  • High blood pressure
  • Diabetes
  • Abnormalities in lipid metabolism
  • Smoking
  • Stress
  • Excess weight
  • Lack of exercise
  • Genetic predisposition
  • Psychosocial factors (depression)
  • Additional factors capable of triggering a heart attack in patients with atherosclerosis include, for instance, fluctuating blood pressure and stressful situations.
  • Blockage of a coronary artery as a result of: narrowing, blood clots or spasms (coronary artery spasm)
  • Age

Diagnosis of heart attack

When symptoms are severe, physicians will immediately suspect a heart attack. The following can be used to confirm a suspected heart attack:

  • ECG: in many cases, this shows typical changes in the electrical impulses travelling through the heart.
  • Analysis of the levels of cardiac biomarkers (enzymes, troponin) in the blood
  • Electrocardiography (cardiac ultrasound) may also be considered.
  • Clinical history and clinical examination
  • Blood tests (troponins T and I, creatine kinase, FABP, LDH)
  • Cardiac catheterization

Treatment for heart attack

If the above-named symptoms have been present more than 20 minutes, the emergency services should be contacted immediately.
A heart attack is a medical emergency. Prompt treatment may be able to limit the damage caused to the heart muscle ("time is muscle").
Place the patient in a semi-reclining position (upper body elevated), reassure the patient, and remove any restrictive clothing. 

  • Emergency treatment
  • Cardiac catheterization
  • Bypass surgery
  • Rehabilitation
Emergency treatment

Emergency treatment provided by the emergency services may include the administration of oxygen, morphine (for pain) and anticoagulants (blood thinning medication).

Very often, the emergency response team will also start an intravenous drip in order to administer medication so as to dissolve the blood clot inside the coronary arteries (referred to as thrombolytic therapy). Systemic thrombolytic therapy should only be administered by the emergency response team if the nearest cardiac catheterization laboratory is more than a 2-hour journey away.

Cardiac catheterization

Once at the hospital, many patients will be treated with catheter-based interventions. A cardiac catheterization laboratory is therefore essential.

Catheter-based procedures allow physicians to make a precise diagnosis and, in many cases a blocked coronary artery can be re-opened using an inflatable balloon (this is referred to as a balloon angioplasty).
This procedure usually involves the implantation of a stent to support the artery wall and keep it open. 

more

Research

  • Effect of intravenous FX06 as an adjunct to primary percutaneous coronary intervention for acute ST-segment elevation myocardial infarction results of the FIRE (Efficacy of FX06 in the prevention of myocardial reperfusion injury) trial.
    Autoren: Atar D, Petzelbauer P, Schwitter J… Butter C, et al. JACC 2009;53:720-9
 
 
 
 
Relevant information

Emergency numbers

  • Emergencies only:
    112
    Our emergency room:
    +49 3338-69 45 21

Contact person

  • Univ.-Prof. Dr. med.
    Christian Butter
    Head of the Department of Cardiology, Immanuel Hospital Bernau Brandenburg Heart Center

    PA to Head of Department Christine Meinecke
    Immanuel Hospital Bernau Brandenburg Heart Center
    Ladeburger Str. 17
    16321 Bernau bei Berlin
    T +49 3338 694-610
    F +49 3338 694-644
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