Sudden cardiac arrest (also called sudden cardiac death (SCD), sudden death, ventricular fibrillation and cardiac arrest) is the sudden loss of cardiac function. Unlike a heart attack – which is a circulation problem where one or more of the arteries delivering blood to the heart are blocked – sudden cardiac arrest is caused by an electrical problem in the heart and is characterized by abnormal heartbeats called arrhythmias. The arrhythmia is called ventricular fibrillation and when it occurs your heart does not pump adequately. Without the pumping function of your heart, no blood is being delivered to other parts of your body, including your brain. Sudden cardiac arrest occurs without warning and is characterized by an abrupt collapse with loss of consciousness and no pulse or breathing.

Sudden cardiac arrest can occur at any age. It can affect anyone – from people in their 40s and 50s with heart disease to young people, who may have an inherited arrhythmia disorder.

Response time is critical for sudden cardiac arrest. The sooner a person is resuscitated, the better chance of recovery. Death can occur within eight to 10 minutes. The number of deaths related to sudden cardiac arrest in the United States each year is more than the total death rate for breast cancer, lung cancer and HIV/AIDS combined. Sudden cardiac arrest is one of the leading causes of death in men and women in the United States, totaling more than 325,000 deaths annually.

If you witness someone collapse from possible cardiac arrest, you can administer Hands-Only™CPR. Even when performed by a bystander, this lifesaving technique has been shown to be as effective as “conventional” CPR in emergencies. There are only two steps to remember:

1. Call 911
2. Push hard and fast in the center of the chest

Don’t worry about whether or not you are doing hands-only CPR “right” or not. You cannot make the victim worse. You can only help. Giving hands-only CPR for a short time to someone who is not really in cardiac arrest is rarely harmful.

Causes of sudden cardiac arrest

The most common underlying reason for people to die suddenly from cardiac arrest is heart disease. Irregular heart rhythms (arrhythmia) cause the heart to suddenly stop beating. Cardiac arrest can be due to:

• Extreme slowing of the heart (bradycardia)
• Ventricular fibrillation (also called ventricular arrhythmias), a condition in which many electrical signals are sent from the ventricles at a very fast, erratic rate. The ventricles are unable to fill with blood and pump, causing a life-threatening situation.
• Scarring from a prior heart attack
• A thickened heart muscle (cardiomyopathy)
• Electrical abnormalities including Wolff-Parkinson-White syndrome and Long QT syndrome and other inherited arryhythmia disorders
• Abnormalities in blood vessels, particularly in the coronary arteries and aorta
• Congestive heart failure

People who have survived a previous heart attack or have a history of congestive heart failure are four to six times more likely to die suddenly from cardiac arrest. Other less common conditions can induce cardiac arrest, including changes in the heart’s normal size and structure, certain types of physical stress, respiratory arrest, drowning, choking and trauma. It also can occur without any known cause.

Risk factors for sudden cardiac arrest include coronary disease and a family medical history of heart problems.

Why choose Ohio State for sudden cardiac arrest treatment?

The Ohio State University Wexner Medical Center has an interdisciplinary program designed to quickly determine causes of sudden cardiac arrest and develop appropriate treatment after the event. Our cardiologists work closely with our Emergency Department to reduce treatment time once an individual with sudden cardiac arrest reaches our hospital. If needed, we also have an outstanding surgery program which includes the ability to offer temporary mechanical support (such as ventricular assisted devices, or VADs) for patients who are in shock and cannot be stabilized.

Learn more about how Ohio State is leading the way in heart & vascular treatment, and helping patients survive.

How Ohio State diagnoses sudden cardiac arrest

There is no method to diagnose this condition prior to its "sudden" occurrence. Once it occurs it must be treated immediately.

How Ohio State treats sudden cardiac arrest

Sudden cardiac arrest often leads to death unless the condition is treated immediately. Cardiopulmonary resuscitation (CPR) is usually necessary to treat a person who has had sudden cardiac arrest.

The best method to treat sudden cardiac arrest at the time it occurs is by an electrical shock delivered to the chest. This is usually performed by help from 911 emergency staff. Until 911 help arrives, if an automatic external defibrillator is available, this device should be used to provide the electrical shock.

Ohio State University offers a team of physicians who specialize in varied aspects of the heart to formulate a plan to care for individuals who survive sudden cardiac arrest and to prevent future episodes.

A series of tests may be used to determine the cause of your sudden cardiac arrest, including:

• Blood tests – Studies to detect substances that leak into the blood when the heart has been damaged.
• Electrocardiogram (EKG/ECG) – A test that records the electrical activity of the heart.
• Chest X-ray – A radiograph or picture of the internal organs of the chest — lungs, heart, ribs, spine and others.
• Nuclear scan – An imaging procedure that enables visualization of organ and tissue structure and function. A tiny amount of a radioactive substance (radionuclide) is used to identify abnormalities.
• Electrophysiology (EP) study – A test to study the heart’s electrical system via insulated electric catheters placed inside the heart.
• Cardiac catheterization – A test that evaluates the blood flow to the heart blood vessels. This test may show the need for a coronary angioplasty or coronary artery bypass graft (CABG) surgery.
• Echocardiogram (also called echo) – This test uses sound waves to determine whether your heart is pumping properly. One of the measurements taken by an echo is the ejection fraction, which is the total volume of blood in the heart’s chambers ejected with each heartbeat.
• Cardiac MRI (cardiac magnetic resonance imaging or CMR) – A non-invasive, sophisticated imaging procedure that uses large magnets and a computer to produce detailed images of the structure and function of the heart while it is beating. This test evaluates the heart structure and function and helps identify any abnormality within the heart that could have led to the sudden cardiac arrest episode.

Depending on the cause of your sudden cardiac arrest, your physician may recommend one of the following options to prevent future recurrences:

• Implantable cardioverter defibrillator (ICD) – insertion of a mechanical device that monitors the heart rhythm and that will provide an immediate shock to treat episodes of sudden cardiac arrest that may occur in the future.
• Coronary angioplasty
• Coronary artery bypass graft (CABG)
• Heart transplant
• Ventricular assist devices (VADs)