Cardiac arrest, also called sudden cardiac death (SCD) is an unexpected, sudden cardiac event that leads to death. SCD is more likely to occur in someone with an underlying cardiac abnormality. It is usually caused by an abnormal heart rhythm (arrhythmia) and is responsible for half of all heart disease deaths.
Causes And Risk Factors For Cardiac Arrest
The most common cause of cardiac arrest is ventricular fibrillation (VF). The heart has a built-in electrical system. In ventricular fibrillation, the electrical signals that control the pumping of the heart suddenly become rapid and chaotic. The lower chambers of the heart, the ventricles, begin fibrillate rather than contract, so they can no longer pump blood from the heart to the rest of the body. Blood cannot flow to the brain, which becomes oxygen-starved. The person loses consciousness in seconds.
Among the conditions that may lead to SCD are:
- Atrial fibrillation
- Coronary artery abnormalities
- Arrhythmogenic Right Ventricular Dysplasia
Patients with pulmonary hypertension are also at risk.
Symptoms of Cardiac Arrest
Often, there are no prior symptoms leading up to a cardiac arrest. However, some symptoms to watch for include:
- Fainting during exercise
- Chest pain with exertion
- Shortness of breath
- Syncope (fainting)
Treatment for Cardiac Arrest
If cardiac arrest is suspected, call 911 immediately. The only known treatments are CPR and defibrillation.
The American Heart Association encourages everyone to learn Hands-Only CPR. Performing CPR while awaiting emergency responders can save a life. Learn more here.
Unless an emergency shock is delivered to the heart to restore its regular rhythm, using a machine called a defibrillator, death can occur within minutes. More than more than 70 percent of ventricular fibrillation victims die before reaching the hospital.
Preventing Cardiac Arrest
To begin with, living a "heart healthy" life can help reduce the chances of cardiac arrest. This means:
- Getting regular exercise
- Eating healthfully
- Maintaining a healthy weight
- Not smoking.
- Treating and monitoring diseases and conditions that contribute to heart problems (such as high blood pressure, high cholesterol and diabetes) is also important.
At St. Joseph's Heart & Vascular Institute, we offer a number of preventative health programs and tools for our patients. Find out more about how we can help you Stay Heart Healthy.
For some patients, preventing cardiac arrest means controlling or stopping the abnormal heart rhythms that may trigger ventricular fibrillation. This may be done through:
- Medications, including ACE inhibitors, beta blockers, calcium channel blockers and other antiarrhythmics
- Implantable cardioverter defibrillators (ICDs)
- Catheter Ablation