Cardiac arrest is a medical emergency that occurs when the heart suddenly stops beating. Unlike a heart attack, which is caused by blocked blood flow, cardiac arrest results from an electrical malfunction in the heart that disrupts its rhythm. This leads to an immediate cessation of blood circulation, depriving the brain and vital organs of oxygen. Within seconds, the person loses consciousness and stops breathing, making rapid intervention critical.
The most common underlying cause is ventricular fibrillation, a chaotic heart rhythm that prevents effective pumping. Risk factors include coronary artery disease, previous heart attacks, heart failure, congenital heart defects, and severe electrolyte imbalances. Cardiac arrest can also occur unexpectedly in otherwise healthy individuals, sometimes triggered by intense physical activity or genetic conditions affecting heart rhythm.
Immediate response is the difference between life and death. Cardiopulmonary resuscitation (CPR) helps maintain blood flow to the brain and organs, while defibrillation with an automated external defibrillator (AED) can restore a normal rhythm. Emergency medical services then provide advanced care, including medications and possible interventions to stabilize the patient. Survival rates are significantly higher when bystanders act quickly before professional help arrives.
Long‑term management focuses on preventing recurrence. Patients may receive implantable cardioverter‑defibrillators (ICDs), medications to control arrhythmias, and lifestyle changes such as diet, exercise, and avoiding smoking. Public awareness and access to AEDs in schools, workplaces, and public spaces are vital in reducing fatalities. Cardiac arrest underscores the importance of preparedness, as timely action can save lives even in the most sudden and severe medical crises.
