What is the primary cause of sudden cardiac arrest?

The primary cause of sudden cardiac arrest is indeed an electrical malfunction of the heart. This occurs when the heart's electrical system fails, leading to an arrhythmia—a disruption in the heart's normal rhythm. This malfunction can prevent the heart from pumping blood effectively, which results in a lack of blood flow to vital organs and ultimately can lead to death if not addressed immediately.

Arrhythmias can be triggered by various factors, including heart conditions, trauma, or intense physical exertion. In many cases, the arrhythmia responsible is ventricular fibrillation, where the heart quivers instead of beating effectively. This highlights the significance of rapid response measures, such as CPR and defibrillation, which can restore a normal rhythm and potentially save the individual's life.

Other options, while related to heart health, do not directly lead to the acute event of sudden cardiac arrest in the same immediate manner. Blocked arteries can lead to heart attacks, low blood sugar typically results in different symptoms, and cardiac muscle disease can contribute to heart failure but is not the primary trigger for sudden cardiac arrest. Understanding these distinctions is crucial for effective lifeguard training and response protocols.