What's the difference between a heart attack and cardiac arrest?

Chest compressions are vital to keep blood and oxygen flowing to the brain and body during a cardiac arrest. — Filepic

Cardiac arrests and heart attacks are different, although heart attacks can lead to cardiac arrests.

A cardiac arrest happens when your heart stops pumping effectively.

This can happen due to an electrical or mechanical cause.

When the heart beats either too fast or too slow, the heart will be unable to pump blood effectively.

This could be due to several causes, such as abnormal blood salt levels, poison, low oxygen levels, and even certain medications.

The heart can also stop pumping effectively if the patient is too dehydrated or has lost a lot of blood.

A blood clot within the lungs or the blood vessels around the heart can also lead to a cardiac arrest.

Heart attacks, on the other hand, are due to blockages of one of the main blood vessels that supply the heart, i.e. the coronary arteries.

Such blockages can be caused by blood clots or the build-up of cholesterol within the artery.

When someone has a heart attack, their heart may stop functioning, which leads to a cardiac arrest.

When a heart attack happens, it’s very important that the blocked coronary artery is opened as soon as possible.

The most effective way of treating a heart attack is via a method called coronary angioplasty, where a balloon or stent is used to open up the blood vessel effectively.

When the blood vessel is opened, the flow of blood is restored and oxygen-rich blood can be delivered to the heart muscle.

The longer the duration of the heart attack, the higher the chance of a cardiac arrest happening due to the heart malfunctioning.

Race against time

When a cardiac arrest happens, healthcare professionals will be in a race against time to restore the spontaneous circulation of blood around the body.

This is because the longer the blood supply is disrupted due to a malfunctioning heart, the longer the brain and other important organs are deprived of blood and oxygen.

The longer the brain is deprived of oxygen, the higher the likelihood that the patient will end up with some degree of brain or mental impairment.

And the longer the cardiac arrest, the lower the likelihood of the patient being saved.

In a cardiac arrest situation, it is important to keep blood pumping to the brain and other organs.

This is why cardiopulmonary resuscitation (CPR) via chest compressions is vital.

By performing chest compressions at a rate of 100 per minute, the bystander performing CPR will be able to maintain adequate blood flow to the brain and other organs to prevent permanent damage and to increase chances of successful resuscitation.

Chest compressions are part of basic life support and can be done by any bystander.

While chest compressions are being performed, the cause of the cardiac arrest needs to be investigated and treated.

Among the causes doctors look for are low blood circulation volume, which may be due to severe dehydration or blood loss, and low oxygen states, especially in cases of suspected choking or patients with underlying lung issues like asthma.

Patients may also have abnormal levels of salts such as potassium in the blood, or increased levels of acid due to certain medications or kidney failure.

Other causes include tension pneumothorax (a collapsed lung), a pulmonary embolus (a blood clot in the lung), toxins such as certain antidepressants or heart medications, or mechanical pressure on the heart caused by a tamponade (accumulation of fluid in the sac around the heart).

A tamponade may be caused by injury to the chest, or even slower processes such as the spread of cancer.

Heart attacks, as mentioned earlier, are also a major cause of cardiac arrests.

A close link

In summary, cardiac arrests and heart attacks are different, but very closely linked.

A cardiac arrest happens when your heart malfunctions and stops pumping blood around your body.

There are both electrical and mechanical causes of cardiac arrest.

The most important thing to do during a cardiac arrest is chest compressions, which helps to pump blood around the body.

Looking for and treating the cause of a cardiac arrest is key to the survival of the victim, and most times, this includes giving an electrical shock to the patient.

Heart attacks are due to blockages within the coronary arteries and can lead to cardiac arrests.

Heart attack treatments such as coronary angioplasty can be life-saving, and in many situations, are done frequently to treat cardiac arrests.

Dr Muhammad Imran Abdul Hafidz is a cardiologist. For more information, email [e-mail]. The information provided is for educational and communication purposes only, and should not be considered as medical advice. The Star does not give any warranty on accuracy, completeness, functionality, usefulness or other assurances as to the content appearing in this article. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.