
Image: Shutterstock
A cardiac arrest refers to when the heart stops functioning, leading to unexpected death, also called cardiac death. It is one the biggest causes of death in the world today, with over half of all heart disease-related deaths ending with cardiac arrests. Indians are at an increased risk of succumbing to heart diseases, and this number has been significantly increasing over the years. According to a WHO census, approximately 4,280 out of every lakh Indians die due to cardiac arrests!
Speaking about the risk, Dr Rajesh T R, Consultant Cardiothoracic and Vascular Surgeon, Kauvery Hospital, Bengaluru, says, “After a cardiac arrest, blood circulation stops. There are four to six minutes before brain death and death occur. Chances of survival reduce by 7-10% with every passing minute.” It is important to note that heart attacks and sudden cardiac arrests are completely different from each other. These words are often used interchangeably, despite the fact they are not the same. So what actually happens during a heart attack and cardiac arrest? Dr Rajesh helps us understand.

Image: Shutterstock
Heart Attack Vs. Cardiac Arrest
The heart muscles require oxygen-rich blood to function, which is provided through the coronary arteries. A heart attack occurs when these arteries are blocked and hence unable to supply blood to the heart. “These blockages need to be addressed immediately, to limit the extent of permanent damage to the heart muscles,” says Dr Rajesh.
In a cardiac arrest, the heart just stops beating. The blood pressure drops and blood supply to all the organs, including the brain is affected. “Without blood flow to the brain, a person will lose consciousness. Death can follow instantaneously unless emergency treatment is instituted. The cause of a sudden cardiac arrest may or may not be related to the heart,” explains Dr Rajesh.

Image: Shutterstock
Causes Of Sudden Cardiac Arrest
“The commonest cause of cardiac arrest is an abnormal heart rhythm, mostly one called Ventricular Fibrillation (VF). Normally, electrical impulses are transmitted through the heart in a systematic fashion, which initiates a sequential contraction of the chambers of the heart, leading to blood being effectively pumped to all organs of the body. In VF, multiple impulses are generated and transmitted through the heart in a rapid, random, and arbitrary way. This results in ineffective contraction of the heart and the blood pressure drops,” says Dr Rajesh.
Additionally, coronary artery disease can cause sudden cardiac arrest, especially if the block develops in the proximal segments of the main coronary arteries. Heart attacks are caused by coronary artery disease, and although different from cardiac arrests, there is a link between them. “A patient suffering from a heart attack can have a cardiac arrest on their way to the hospital. Valvular heart diseases like Aortic Stenosis can also cause sudden cardiac arrest,” highlights Dr Rajesh.

Image: Shutterstock
Management Of Sudden Cardiac Arrest – Basic Life Support
The American Heart Association has simplified the emergency management of sudden cardiac arrest. This training, called Basic Life Support or BLS, can now be easily and effectively taught, and is easy enough to emulate even for someone with no medical background. Dr Rajesh adds, “BLS is very simple and everyone should be trained to do it. Using the technique of BLS, a trained person can keep a patient, who has suffered a sudden cardiac arrest, alive until medical help arrives.”
Dr Rajesh mentions that when a person collapses, the most common cause is sudden cardiac arrest. He lists the steps of BLS in brief:
- The first step is to ensure that the environment is safe for both the victim and the BLS provider. If not, then move the victim to a safe place.
- Call for medical help.
- Check for breathing and pulsation. Look at the chest for movements, Check the pulsations in the neck. This should not take more than 10 seconds.
- If neither is present, then start chest compressions. The chest compression to breaths ratio should be 30:2, i.e., two breaths for every 30 chest compressions. A ‘Hands-only CPR’ protocol is also recommended for laypersons, especially during present COVID-19 times, wherein only chest compressions are recommended without breaths. This is also shown to be very effective.
Also read: Try These 8 Best Yoga Poses For Stress Relief