Final answer:
A Transient Ischemic Attack (TIA) is the condition where cerebral ischemia is due to systemic hypotension, characterized by a temporary disruption of blood flow to the brain.
Step-by-step explanation:
The condition in which cerebral ischemia is caused by systemic hypotension is known as a Transient Ischemic Attack (TIA). A TIA occurs when there is a temporary disruption of blood to the brain, which can be caused by various reasons, including systemic hypotension. Unlike a full-fledged stroke, the effects of a TIA are temporary and usually resolve within 24 hours. However, it is a serious warning sign that could indicate the possibility of a future stroke. Systemic hypotension can lead to inadequate cerebral perfusion pressure and subsequently ischemia, as the brain does not receive enough oxygen and glucose due to lowered blood flow.