Sudden suspension of cardiac activity that is usually due to ARRHYTHMIA, in contrast to heart attack (MYOCARDIAL INFARCTION) which occurs due to blockage. The sudden suspension of cardiac activity generally requires RESUSCITATION.

Unexpected rapid natural death due to cardiovascular collapse within one hour of initial symptoms. It is usually caused by the worsening of existing heart diseases. The sudden onset of symptoms, such as CHEST PAIN and CARDIAC ARRHYTHMIAS, particularly VENTRICULAR TACHYCARDIA, can lead to the loss of consciousness and cardiac arrest followed by biological death. (from Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005)

Synonyms: Cardiac Arrests, Sudden, Cardiac Arrest, Sudden, Death, Sudden Cardiac, Sudden Cardiac Arrest, Sudden Death, Cardiac, Sudden Cardiac Death, Cardiac Death, Sudden, Arrest, Sudden Cardiac, Cardiac Sudden Death, Death, Cardiac Sudden, Death, Sudden, Cardiac