Skip to main content

Sudden Cardiac Arrest

What is Sudden Cardiac Arrest?

Sudden Cardiac Arrest is a serious and life-threatening medical emergency. During Sudden Cardiac Arrest, heart function stops — abruptly and without warning. This causes a rapid loss of consciousness (fainting). Without immediate treatment with defibrillation (an electric shock to the heart), brain damage and death can occur.¹

Sudden Cardiac Arrest Is Not the Same as a Heart Attack

The definitions of Sudden Cardiac Arrest and heart attack are completely different. A heart attack is a "plumbing" problem caused by one or more blockages in the heart's blood vessels that prevent proper flow. A person having a heart attack is awake and breathing.

How a healthy heart works

Sudden Cardiac Arrest is defined as an electrical problem, caused by an arrhythmia (irregular heartbeat) that prevents the heart from pumping blood to the brain and vital organs. A person experiencing Sudden Cardiac Arrest is unconscious and not breathing.

Sudden Cardiac Arrest (SCA) explained

Factors such as high blood pressure or heart disease increase the risk for Sudden Cardiac Arrest. It’s not uncommon for a person to have a heart problem and not be aware of it until after Sudden Cardiac Arrest has occurred.

Did you know? Every 40 seconds, someone dies from Sudden Cardiac Arrest².

Every 40 seconds someone dies from Sudden Cardiac Arrest


1. National Heart, Lung, and Blood Institute – What is Sudden Cardiac Arrest? Available at: Accessed June 7, 2014.
2. American Heart Association. Heart Disease and Stroke Statistics – 2010 Update. Circulation. 2013;127:e6-e245.

The law restricts these devices to sale by or on the order of a physician. Indications, contraindications, warnings and instructions for use can be found in the product labelling supplied with each device. Information for the use only in countries with applicable health authority product registrations.Content of this website is for Information Purposes only and not meant for product promotion or medical diagnostic. This information does not constitute medical or legal advice, and Boston Scientific makes no representation or warranty regarding this information or its completeness, accuracy or timeliness.
Accordingly, Boston Scientific strongly recommends that you consult with your physician on all matters pertaining to your health or to address any questions.