CVA vs ischemic stroke

CVA and ischemic stroke both are nouns.

Word	Noun	Adjective	Verb	Adverb
CVA	Yes	No	No	No
ischemic stroke	Yes	No	No	No

As nouns, ischemic stroke is a hyponym of CVA; that is, ischemic stroke is a word with a more specific, narrower meaning than CVA:

CVA: a sudden loss of consciousness resulting when the rupture or occlusion of a blood vessel leads to oxygen lack in the brain
ischemic stroke: the most common kind of stroke; caused by an interruption in the flow of blood to the brain (as from a clot blocking a blood vessel)

Other hyponyms of CVA include ischaemic stroke, haemorrhagic stroke, hemorrhagic stroke.

CVA (noun)	ischemic stroke (noun)
a sudden loss of consciousness resulting when the rupture or occlusion of a blood vessel leads to oxygen lack in the brain	the most common kind of stroke; caused by an interruption in the flow of blood to the brain (as from a clot blocking a blood vessel)