Sudden cardiac death occurs due to heart thrombosis or heart failure caused by various reasons whereby the heart cannot supply blood, leading to death. Most people experience hypotensive shock, insufficient blood and oxygen supply to the body before dying, thus appearing pale, with low blood pressure, and even cyanosis, with cessation of breathing and heartbeat. Some individuals suffer from heart thrombus dislodging into the brain, causing cerebral arterial infarction. Such extensive cerebral infarctions can also lead to the cessation of heartbeat, resulting in insufficient blood and oxygen supply throughout the body, manifesting as pallor and cyanosis.