What is the term for the sudden stoppage of heart action?

The term for the sudden stoppage of heart action is cardiac arrest. This condition is characterized by the heart's abrupt cessation of function, leading to an inability to pump blood effectively, which can result in loss of consciousness and, if not treated immediately, can lead to death.

In cardiac arrest, the heart may stop beating entirely or may experience an erratic rhythm that prevents it from pumping blood. Recognizing and responding to cardiac arrest quickly is critical for survival, which is why training in cardiopulmonary resuscitation (CPR) and the use of an automated external defibrillator (AED) is emphasized in emergency response scenarios.

The other terms listed refer to different conditions that do not exactly describe the immediate failure of the heart's action. Heart failure refers to a chronic condition where the heart can no longer pump sufficient blood to meet the body's needs. A heart attack, or myocardial infarction, occurs when blood flow to a part of the heart is blocked, causing damage to the heart muscle. Arrhythmia refers to irregular heartbeats, which may occur in various forms but do not necessarily mean that the heart has stopped beating altogether.