What happens of there is no blood flow to brain arteries?

Not self-evident?: If there is no flow in brain arteries, the brain that those arteries go to and are in is not a living brain. But you don't need a doctor to tell you that. Your mother can tell you that. What's more, you can substitute the words heart, lung, kidney, muscle, bowel, thyroid, in fact any tissue or organ for "brain" and get the same result for that tissue or organ: No flow, no go.

Stroke: When an artery in the brain gets blocked the area of the brain that is fed by the artery dies and this is called a stroke. If there is no blood flow to the brain at all it is called brain death.