I30-I52: Other forms of heart disease

I46: Cardiac arrest

Cardiac arrest is a severe and life-threatening condition that occurs when the heart abruptly stops beating. This causes blood flow to cease to vital organs, resulting in a loss of consciousness and a lack of pulse. It is commonly caused by a disruption in the electrical activity of the heart, leading to abnormal or absent heart rhythms known as arrhythmias. The most common type of deadly arrhythmia in cardiac arrest is ventricular fibrillation, which involves chaotic and rapid electrical impulses in the heart's lower chambers. Symptoms leading up to cardiac arrest may include chest pain, shortness of breath, dizziness, and nausea, but cardiac arrest itself is characterized by a loss of responsiveness and absence of normal breathing. If blood flow is not restored promptly, death or irreversible brain damage can occur within minutes.