An ST-elevation myocardial infarction (STEMI) is a type of severe heart attack caused by a complete blockage of a coronary artery. This changes the heart’s oxygen supply, blood flow, and electrical current in the lower chambers.

These types of heart attacks are extremely serious and can be life threatening. Up to 10% of people who experience a STEMI heart attack die within 30 days.

A person experiencing STEMI may feel chest pain, pressure, or tightness. They may also feel nauseous and have difficulty breathing. If someone has these symptoms, they require immediate medical attention.

This article explains STEMI heart attacks, their symptoms, diagnosis, and treatment options.

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A STEMI heart attack is a form of acute coronary syndrome (ACS). This term describes sudden blockages to the heart’s blood flow.

Heart attacks may be STEMI, meaning the coronary artery is completely blocked. Or they may be non-ST-elevation myocardial infarction (NSTEMI), meaning the artery is partially blocked and severely reducing blood flow.

Myocardial infarction is the medical name for heart attack. It occurs when an area of the heart muscle, the myocardium, becomes damaged or dies after the blood supply has a blockage.

Read more about NSTEMI here.

The most common symptom of a STEMI heart attack is chest pain. A person may feel tightness, pressure, or a crushing feeling in the middle of the chest.

Other symptoms may include:

  • sweating
  • shortness of breath
  • nausea or vomiting
  • pain in the jaw, neck, back, or one or both arms
  • dizziness or lightheadedness

Different sexes may experience different symptoms. For example, although the most common heart attack symptom is chest pain, females may experience other symptoms such as shortness of breath, nausea, and back or jaw pain.

If someone experiences any of the above symptoms, they should seek medical attention immediately. Every second is crucial during a STEMI heart attack, and it is essential to get help straight away.

Most hospitals have an emergency department that can provide prompt care and treatment. A person should call 911 or their local emergency number if they are experiencing chest pain.

Read more about how to spot a heart attack here.

The cause of a STEMI heart attack is a blockage in one of the coronary arteries supplying the heart. This happens when a fatty substance called plaque builds up in the arteries causing inflammation and stress.

As a result, the stress can tear the artery. The body then attempts to heal the injury, and blood clots form at the site. These blood clots can block the artery, disrupting the blood and oxygen supply to the heart and damaging the muscle. When the heart muscle dies, this is a myocardial infarction.

The major risk factors for STEMI heart attacks are:

Treatment for STEMI heart attacks depends on the individual. It may include:

  • drugs to reduce chest pain and stabilize the heart
  • drugs to thin the blood and break up clots
  • opening the blocked artery with angioplasty and stent placement through a cardiac catheterization
  • medication to reduce heart rate and blood pressure
  • oxygen therapy to improve breathing
  • bypass surgery

A STEMI is the most serious type of heart attack. The in-hospital death rate ranges from 4 to 12% and around 10% at 1-year follow-up. However, this figure jumps to about 38% if complications arise, such as sudden cardiac arrest, before making it to the hospital.

A person’s outlook may also depend on the location of the blockage and how much of the heart muscle has been damaged. It may also depend on the person’s age, overall health status, and how quickly they received medical attention.

The best way to prevent heart attacks is to understand the risk factors and take steps to reduce them. This may include lifestyle measures such as:

  • quitting smoking
  • eating a balanced diet
  • managing weight
  • increasing physical activity
  • reducing stress levels
  • managing blood pressure and cholesterol levels
  • managing diabetes

People should discuss their heart health with their doctor, who can advise them on the best preventive measures.

A STEMI heart attack is a medical emergency that requires immediate treatment to reduce the chances of long-term damage and death.

It occurs when a coronary artery becomes completely blocked, limiting the heart’s blood supply and damaging the muscle. Symptoms include chest pain, sweating, shortness of breath, and nausea.

The best way to prevent STEMI heart attacks is to be aware of the risk factors and take steps to reduce them. This may include lifestyle changes such as quitting smoking, eating a balanced diet, and increasing physical activity.

It is important to seek medical attention immediately if STEMI heart attack symptoms occur. The chances for a successful outcome depend on how quickly treatment begins.