Cardiac Arrest

What is a cardiac arrest?

A cardiac arrest is when the heart suddenly stops working. The person having a cardiac arrest may or may not have diagnosed heart disease. It is also called sudden cardiac arrest. Death (also called sudden cardiac death) will occur within minutes after symptoms appear if the cardiac arrest is not treated right away.

What causes a cardiac arrest?

The most common reason for cardiac arrest is a blocked blood vessel in the heart (coronary heart disease) or poor heart muscle function. There are other causes for cardiac arrest. These include inherited problems that bring about rare disorders in the heart muscle or the heart’s electrical system (e.g., Long QT Syndrome, Arrhythmogenic Right Ventricular Cardiomyopathy or ARVC). Some cardiac arrests are due to the extreme slowing of the heart. This is called bradycardia.

Cardiac arrest can also happen with respiratory arrest, electrocution, drowning, choking and trauma. Sometimes, the reason for a cardiac arrest is not known.

What causes a cardiac death?

Most cardiac deaths happen when the electrical impulses in the diseased heart become disorganized (ventricular fibrillation), too fast (ventricular tachycardia), or both. This causes an irregular heart rhythm and the heart can no longer pump blood.

Brain death and possibly permanent death will within 6-10 minutes after someone has a cardiac arrest.

Can the heart be started again after a cardiac arrest?

The heart can be restarted if it is treated within the first few minutes of stopping. This involves CPR and giving an electric shock or defibrillation to the heart to help it restore a normal heartbeat. A person's chance of survival is reduced by about 10 percent with every minute that passes without CPR or defibrillation. Very few people have survived after 10 minutes without CPR or defibrillation. It is important for the person having a cardiac arrest to receive treatment right away.

How many people survive cardiac arrest?

The exact number of cardiac arrests that happen each year is unknown. Health researchers think about 95 percent of cardiac arrest victims die before reaching hospital. The survival rate is a lot higher in cities where defibrillation is done within the first 5 to 7 minutes of having an arrest.

How can survival rates be increased?

Good long term survival rates are the result of early CPR, rapid defibrillation and being sent to hospital for specialized care. This means more people getting CPR training and using it in an emergency. It also means getting more Automated External Defibrillators (AED) put in common public places like shopping malls and school hallways. If Canadian communities increased their cardiac survival rate to 20 percent per year, it would mean that over 4000 people a year could be saved from cardiac arrest!

Simply put, reacting quickly by performing CPR, using an AED if one is available and calling 911 right away saves lives.

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