THE TERM "cardiac arrest" implies a sudden cessation of the heart's pumping function due either to ventricular asystole (electrical or mechanical) or to ventricular fibrillation. Although cardiac arrest is a terminal event in all fatal illnesses, this discussion will deal with the problem of cardiac arrest (usually unexpected) in people who otherwise might recover.
The causes of reversible cardiac arrest are many, including acute hypoxemia (food asphyxiation, pulmonary edema, drowning, etc) accidental electrocution, electrolyte imbalance, acute pulmonary embolism, drug toxicity (digitalis, quinidine, etc) aortic stenosis, advanced heart block, and cardiac trauma; however, the most important cause in adults is coronary artery disease. Putting it another way, more than half of deaths due to coronary artery disease are sudden and unexpected, usually occurring outside of the hospital.
Cardiac arrest should be considered whenever a person suddenly collapses and loses consciousness. A grand mal seizure may occur at the same time.
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