How high would blood pressure need to be for a stroke to occur? sometimes my b/p goes to 160/100 @ doc but goes down after. is this normal?

Any level: From low to normal to high can occur with either heart attack or stroke. With very high 150and greater systolic and 100 or so diastolic a number of bad things can happen: aortic tear-dissection, and heart attack or stoke may evolve. With high pressure intracranial aneurysm may burst, o r the brain may bleed. Complex sets of diagnostic issues.