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:
Slow Heart Beat (Bradycardia) An abnormally slow sinus heart rate is called the âsick sinus syndromeâ and, if severe, results in symptoms of fatigue. In some such cases a permanent pacemaker is needed to be implanted to generate a normal heart rate. Many people with sick sinus syndrome also develop atrial fibrillation.