SCA is treatable in most cases — especially when it is caused by ventricular fibrillation — as long as treatment is given quickly. Treatment requires cardiopulmonary resuscitation (CPR) and defibrillation. This must begin immediately to be effective, ideally within three to five minutes of collapse. Even the fastest ambulance response may not arrive in time. That is why prompt action by bystanders is critical, and why learning CPR and how to use an AED can save lives.
If someone is unresponsive and not breathing normally, suspect cardiac arrest and act immediately: call 999, start CPR, and use a nearby AED if one is available. The dispatcher will guide you through CPR if you are unsure. When cardiac arrest occurs, the person is clinically dead, but prompt bystander action can restore life.
Once the ambulance service arrives, paramedics will continue resuscitation and provide advanced cardiac life support. Patients who remain in a coma after successful resuscitation may be treated with targeted temperature management (controlled cooling) to protect the brain. All survivors of cardiac arrest should be reviewed by a cardiologist or cardiac electrophysiologist for follow-up assessment and treatment.