Cardiac Arrest

What is cardiac arrest?

Cardiac arrest happens when the heart stops beating or when it beats too fast and stops pumping blood. It is caused by an issue with the electrical system that controls the heart rate. The symptoms of cardiac arrest usually start with no warning, so it is also referred to as sudden cardiac death.

Cardiac arrest usually happens in older adults, but it can affect anyone of any age. It can happen to people with heart disease and those with no history of a heart condition. People who have previously had a heart condition or heart attack are at a higher risk of cardiac arrest.

During cardiac arrest, you become unconscious. It can be fatal within a matter of minutes as the body stops receiving oxygen. Receiving immediate help can increase the chances of survival.

If you see someone having cardiac arrest, always seek urgent medical assistance. Giving CPR can keep oxygen in the lungs and defibrillation delivers an electrical shock which can restore normal heartbeat.

What are the warning symptoms of cardiac arrest?

Cardiac arrest warning symptoms can include:

• Dizziness
• Heart palpitations
• Lightheadedness
• Loss of consciousness (fainting)

Before losing consciousness, there may be other signs of cardiac arrest, which can include:

• Chest pain
• Nausea/vomiting
• Shortness of breath
• Weakness

Cardiac arrest can also happen with no symptoms immediately before.

What causes cardiac arrest?

Before a cardiac arrest happens, the heart’s electrical system, which regulates the heartbeat, fires abnormal impulses. These override the normal impulses which start a heartbeat normally.

This leads to arrhythmias, which are abnormal heart rhythms and cause most cardiac arrests. The most common arrhythmia leading to cardiac arrest is called ventricular fibrillation (or v-fib). This is a life-threatening, disorganized firing of impulses, which come from the heart’s lower chambers, called the ventricles. If this happens, the heart can’t pump blood and no oxygen can reach the body.

A range of other factors and medical conditions can lead to abnormal heart rhythms and are underlying causes of cardiac arrest. These underlying causes include:

• Cardiomyopathy
• Coronary artery disease
• Congenital heart conditions
• Heart attack
• Heart failure
• Infectious disease
• Injury or illness that has caused major blood loss
• Respiratory conditions

What are the risk factors for cardiac arrest?

The following may increase the risk of cardiac arrest:

• A history of abnormal heart rhythms
• A family history of cardiac arrest
• A previous cardiac arrest
• A congenital heart disease
• Diabetes
• Heart attacks
• Heart Failure
• Heart valve disease
• Hypertrophic cardiomyopathy
• Obesity

What happens after cardiac arrest?

People who survive cardiac arrest often experience complications that last for a long time. These may include:

• Cognitive issues (how we learn and understand things)
• Sensory issues
• Mental health problems
• Muscle weakness or paralysis

How is cardiac arrest diagnosed?

Cardiac arrest happens suddenly and can be fatal very quickly. Recognizing symptoms immediately is very important as it is the only way to diagnose cardiac arrest. If someone has lost consciousness, has no pulse and isn’t breathing, they may be having a cardiac arrest and require urgent medical assistance.

How is cardiac arrest treated?

Cardiac arrest can be treated, but treatment must begin immediately. Survival rates are improved the faster treatment is given.

If treatment is given after 8 minutes, cardiac arrest is usually fatal. Brain damage can happen within 5 minutes if CPR isn’t administered.

Chest compressions can save someone’s life by keeping blood and oxygen circulating until medical help arrives. If a defibrillator is available, it must be used as it offers the best chance of survival.

When emergency responders arrive, they will defibrillate the patient to try and restart their heart. An electrical current travels to the heart via paddles that are placed on the chest, which restores the normal impulses.

Anti-arrhythmics will then be delivered intravenously, which are medications that aims to restore the heart’s normal electrical rhythm.

Can cardiac arrest be prevented?

Cardiac arrest can be prevented. Being aware of risk factors such as a family history of abnormal heart rhythms, can make you more aware of your risk and ways you can avoid them.

Cardiac screening can identify your risk for cardiac arrent. This will include tests such as:

• Ambulatory monitoring
• Blood tests
• Cardiac catheterization
• Echocardiogram (echo)
• Electrocardiogram (ECG or EKG)
• Electrophysiology study
• Cariac MRI (magnetic resonance imaging)

The following treatments can prevent cardiac arrest or lower the risk of it happening again:

• Implantable cardioverter defibrillator (ICD)
• Medicines like beta-blockers
• Other arrhythmia treatments
• Surgery like coronary artery bypass surgery or angioplasty to fix blocked heart arteries

Addressing conditions and factors that put you at increased risk of cardiac arrest can also reduce the risk. This includes:

• Being physically active
• Eating a heart-healthy diet
• Maintaining a healthy weight
• Quitting smoking

Look after your heart

With so many people in the UAE living with at least one risk factor for heart disease, a risk factor for cardiac arrest and many other heart conditions, the team at Cleveland Clinic Abu Dhabi’s Heart & Vascular Institute recommend adults should undergo comprehensive cardiac screening to better understand and identify potential risk factors. Learn more.