5 Signs of Cardiac Arrest: Symptoms, Causes, Treatment

How is cardiac arrest different from a heart attack?

• Cardiac arrest is when the heart stops beating completely. It occurs when there is a problem with the rhythmic beating of the heart.
• A heart attack occurs when blood flow to the heart is blocked. During a heart attack, the heart usually does not suddenly stop beating and the chances of survival are greater than those in cardiac arrest.

A heart attack increases your risk of sudden cardiac arrest.

What causes cardiac arrest?

The usual cause of sudden cardiac arrest is arrhythmia. Arrhythmia refers to the abnormal or irregular heart rhythm that occurs when there is a problem with the electrical activity of your heart.

The most common heart rhythm abnormalities that lead to cardiac arrest are ventricular fibrillation and ventricular tachycardia.

• Ventricular fibrillation refers to the arrhythmia that begins in the lower chamber of your heart (ventricle).
• Ventricular tachycardia refers to the increased heart rate of more than 100 beats per minute that arises from the ventricle.

Other heart conditions that can lead to cardiac arrest include:

What increases your risk of cardiac arrest?

Certain factors increase your risk of cardiac arrests, such as:

How is cardiac arrest diagnosed?

Cardiac arrest occurs without warning. Because it can result in sudden death, doctors start emergency treatment just by looking at the signs and symptoms. Doctors will first try to rule out other causes of fainting in the person before arriving at the diagnosis of cardiac arrest. If possible, an electrocardiogram test may be performed.

If you are at the risk of cardiac arrest, your doctor may refer you to a cardiologist, a doctor who specializes in the diagnosis and treatment of heart diseases. The cardiologist may ask you to get various heart health tests to check the functioning of your heart.

The tests used to identify cardiac arrest include:

• Blood tests (particularly potassium, magnesium, cholesterol, homocysteine, and hormone levels)
• A stress test
• X-ray of the chest (to check if there is any structural problem in your heart)
• Nuclear scan (to identify blood flow problems to your heart by injecting a tiny amount of radioactive material into your bloodstream)
• Coronary catheterization (injection of a liquid dye into the arteries of your heart to detect blockages in the arteries)

How is cardiac arrest treated?

If you notice symptoms of cardiac arrest in yourself or someone else, call 911 immediately. It is important to get emergency medical help because prompt treatment improves your chances of survival greatly.

If you see someone with a heart attack, you can start performing cardiopulmonary resuscitation (CPR), which is explained on websites of organizations such as the American Heart Association, Centers for Disease Control and Prevention, and Red Cross. 

Once you reach the emergency room, your doctor may perform CPR. They may administer an electrical shock (defibrillation) to the heart to get the heart pumping again.

Your doctor may ask to you follow certain lifestyle modification steps that include:

• Not smoking
• Maintaining a healthy weight
• Drinking alcohol in moderation
• Eating a heart-healthy diet
• Staying physically active
• Managing stress levels

If you have heart diseases or other medical conditions that make you vulnerable to developing cardiac arrest, your doctor may put you on medications for managing high cholesterol, hypertension, or arrhythmia.

If you have a known risk of cardiac arrest, your doctor might recommend an implantable cardioverter–defibrillator.