Sudden Cardiac Arrest (SCA) is the loss of blood flow through the heart that causes the heart to stop beating. If not treated immediately, death will occur. Sudden heart failure is different from a heart attack, which is caused by reduced blood flow to the heart.
SCA usually is caused by coronary heart disease. Other causes include:
- Extreme physical stress
- Intense physical activity
- Low levels of potassium or magnesium
- Major blood loss
- Lack of oxygen
Inherited diseases that cause arrhythmias can result in a higher chance of SCA. In addition, structural changes to the heart, such as due to an enlarged heart or heart disease, can lead to SCA.
Fainting with no signs of a pulse or heartbeat are typically the first symptoms. Sometimes people will experience a fast heartbeat or dizziness before fainting:
Up to an hour before a SCA, some people may experience:
- Chest pain
- Vomiting or nausea