Brain ischemia (aka cerebral ischemia, cerebrovascular ischemia) is a condition in which there is insufficient blood flow to the brain to meet metabolic demand.This leads to poor oxygen supply or cerebral hypoxia and thus to the death of brain tissue or cerebral infarction / ischemic stroke.ther effects that may result from brain ischemia are stroke, cardiorespiratory arrest, and irreversible brain damage. An interruption of blood flow to the brain for more than 10 seconds causes unconsciousness, and an interruption in flow for more than a few minutes generally results in irreversible brain damage.
A. If the heartbeat is too slow, usually considered a rate below 60 beats a minute, not enough oxygen-rich blood flows through the body. The symptoms of a slow heartbeat are:
1 These medicines can slow your heartbeat too much.  You faint or have other symptoms of a slow heartbeat. For example, this may happen if the main artery in your neck that supplies your brain with blood is sensitive to pressure. Just quickly turning your neck can cause your heart to beat slower than normal.