Cardiac Arrest – What is It?

Cardiac arrest stops the heart, preventing blood from flowing to the brain. It can kill within minutes unless treated immediately with CPR, chest compressions and an electric shock from a defibrillator.

Those who survive cardiac arrest may need therapy to process their emotions. One in 10 who go into sudden cardiac arrest die, but the survival rate doubles or triples if bystanders give CPR.

Risk Factors

A sudden cardiac arrest kills people quickly, often within minutes. It’s different from a heart attack (myocardial infarction). The main risk factor for cardiac arrest is coronary artery disease, with 80% of sudden deaths linked to this condition. Other risk factors include smoking, a family history of coronary artery disease, and an abnormal heart rhythm called ventricular arrhythmias, especially long QT syndrome and Brugada syndrome.

Some medicines and illnesses raise the risk of arrhythmias, including a number of over-the-counter medications. Injuries, like getting hit in the chest with a hard blow from a sports ball or car crash, also raise the risk of cardiac arrest. A person’s risk for cardiac arrest also increases with age. Men have a greater risk for cardiac arrest than women, but the gender gap narrows after middle age.

Arrhythmias

Heart arrhythmias occur when the electrical signals that control a normal heartbeat are disrupted. These irregular heartbeats can cause your heart to beat too quickly, too slowly or with an abnormal rhythm. Arrhythmias can range from a minor nuisance to a life-threatening problem.

Supraventricular arrhythmias come from the top parts of your heart and can feel like a racing or fluttering heartbeat. Ventricular arrhythmias, which come from the lower chambers of your heart, can be dangerous and require emergency evaluation.

Arrhythmias are often caused by pre-existing conditions such as coronary artery disease, sleep apnea, diabetes or high blood pressure. They can also be triggered by certain medications, alcohol, illegal drugs or stimulants such as caffeine and nicotine. The natural aging process can also be a trigger.

Heart Attacks

A heart attack occurs when a blockage in the coronary arteries prevents oxygen-rich blood from reaching the heart. This can cause heart damage and death. It’s not the same as sudden cardiac arrest (SCA).

SCA happens when electrical impulses in the heart change pattern and disrupt the heartbeat. This stops blood flow to the brain and other organs, leading to unconsciousness or death if not treated right away.

You can’t predict when you will have a heart attack, but you can reduce your risk by following healthy lifestyle habits and seeing your doctor for regular checkups. If you have a history of cardiac arrest, your doctor may recommend an implantable defibrillator or other devices to prevent future episodes. In some cases, you might need to take medication for certain conditions that can increase your risk of heart attack or arrhythmias.

CPR

While cardiac arrest can be fatal, immediate treatment can increase a person’s chance of survival. This includes calling 911 and undergoing cardiopulmonary resuscitation (CPR), which involves rescue breathing and chest compressions to circulate oxygenated blood to the heart and brain.

CPR also helps prevent oxygen-starved tissue damage that can occur in four to six minutes. This is because the heart stops pumping blood, and without oxygen in the body, cell and tissue death can occur.

The CPR steps are the same for adults and children, although the technique for babies and young children (0-5 years old) is slightly different. People who suffer from a cardiac event may grunt, snore or take gasping breaths, but these are not signs of breathing normally and they still need CPR.

Defibrillation

A defibrillator is a medical device that sends an electric shock to the heart to restore a normal rhythm. The shock may be necessary to stop dangerous arrhythmias or to prevent sudden cardiac arrest (SCA).

A person who has collapsed with SCA needs emergency treatment right away. Without it, they’ll die within a few minutes due to oxygen-poor blood.

The best chance of survival comes from a combination of quick emergency treatment that includes cardiopulmonary resuscitation (CPR) and defibrillation. CPR keeps enough oxygen in the lungs to get to the brain, while defibrillation quickly returns a normal heart rhythm. Defibrillation is typically done with an automated external defibrillator (AED) that can analyze the heart rhythm and advise when a shock is needed. The high-energy shock may feel like a kick in the chest, but it’s not painful for most people.

Go Home