Cardiac arrest is when the heart suddenly stops pumping blood around the body.
It is a life-threatening emergency and different from a heart attack, even though the two are often confused. When the heart stops, blood and oxygen can no longer reach the brain and other vital organs. Without immediate treatment, cardiac arrest can cause death within minutes.
The heart beats because of electrical signals that control how the muscles contract. In cardiac arrest, these signals go wrong, leading to an irregular rhythm called an arrhythmia. The most common arrhythmia linked to cardiac arrest is ventricular fibrillation, where the lower chambers of the heart quiver instead of pumping properly.
This electrical problem means the heart cannot pump blood effectively. In some cases, the heart may stop beating altogether.
No, they are different conditions. A heart attack happens when blood flow to part of the heart muscle is blocked, often by a clot or plaque build up. The heart usually keeps beating during a heart attack, although it is under strain.
Cardiac arrest, on the other hand, means the heart stops working suddenly. Sometimes a heart attack can trigger a cardiac arrest, but they are not the same. Knowing the difference is important, because both need urgent treatment but in different ways.
Someone having a cardiac arrest will usually collapse suddenly. They will lose consciousness and will not be breathing normally, or may stop breathing altogether. They will have no pulse.
Unlike a faint, the person does not wake up within a minute or two. Without immediate help, they will not survive. This is why recognising cardiac arrest quickly and starting emergency care is so important.
If someone collapses and is not breathing, the first step is to call 999 immediately. Paramedics can provide advanced care, but while waiting, cardiopulmonary resuscitation (CPR) should be started straight away.
CPR involves pressing hard and fast in the centre of the chest to keep blood flowing to the brain and organs. If a defibrillator is available, it should be used as soon as possible. Defibrillators give an electric shock to reset the heart’s rhythm and can greatly increase survival chances.
There are several possible causes. The most common is coronary heart disease, where narrowed arteries reduce blood supply to the heart. A heart attack caused by this disease can sometimes trigger cardiac arrest.
Other causes include heart rhythm disorders such as ventricular tachycardia or atrial fibrillation, heart failure, and inherited conditions that affect the electrical system of the heart.
Cardiac arrest can also be caused by severe blood loss, choking, drowning, electrocution, or trauma. Sometimes it happens with no clear warning or known cause.
People with heart disease are at the highest risk, especially those who have already had a heart attack or live with heart failure. Family history also matters, as inherited heart rhythm disorders can increase risk.
Age plays a role, with older adults more likely to experience cardiac arrest, but it can happen to younger people too, particularly athletes with undiagnosed heart conditions. Lifestyle factors such as smoking, obesity, and lack of exercise also contribute to higher risk.
Not all cases can be prevented, but many risk factors can be reduced. Looking after heart health by keeping blood pressure, cholesterol, and blood sugar under control lowers the risk. Stopping smoking, eating a balanced diet, staying active, and limiting alcohol all protect the heart.
For people with known heart rhythm problems, doctors may recommend implantable cardioverter defibrillators (ICDs). These small devices are placed under the skin and can deliver a shock automatically if dangerous rhythms are detected, preventing cardiac arrest.
Surviving cardiac arrest is life-changing. Some people recover quickly, while others may experience memory problems, tiredness, or emotional difficulties. Rehabilitation and follow-up care are important for both physical and mental recovery.
Lifestyle changes become especially important after a cardiac arrest. Following medical advice, taking prescribed medicines, and attending regular check-ups all reduce the chances of future heart problems. Support from family, friends, and healthcare teams also plays a key role in long-term recovery.
Yes, survival is possible, but it depends heavily on how quickly treatment is given. Every minute without CPR or defibrillation reduces the chances of survival by about 10%. This is why knowing basic first aid and how to use a defibrillator can save lives.
In the UK, public access defibrillators are now widely available in places like train stations, schools, and shopping centres. When used quickly, they can more than double the chances of surviving a cardiac arrest.
Cardiac arrest is when the heart suddenly stops pumping blood, causing loss of consciousness and breathing. It is a medical emergency that is different from a heart attack, although the two are linked. The main signs are sudden collapse, no breathing, and no pulse.
Immediate action—calling 999, starting CPR, and using a defibrillator if available—is vital to save lives. While not all cases can be prevented, reducing risk factors such as smoking, high blood pressure, and poor diet can protect heart health. For survivors, follow-up care and lifestyle changes are key to recovery.
Disclaimer: Seonat provides general health information for educational purposes only. This content is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your GP or another qualified health provider with any questions about a medical condition or before making health decisions.
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