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:
Your doctor can determine whether or not your heart rate is abnormally fast or slow, since the significance of an abnormal heart rate depends on the situation. For example, a teen or adult with a slow heart rate might begin to show symptoms when the heart rate drops below 50 beats per minute. However, keep in mind that trained athletes have a lower resting heart rate â so a slow heart rate in these people isn't considered abnormal if no symptoms are associated with it.