It's still getting some base level oxygen less because of the stenosis and ischemia but it still gets some oxygen.

Now, a word that you might hear in a medical context is stenosis , and the word just refers to the narrowing, usually of a blood vessel.

They all imply some sort of narrowing, or stenosis, of arteries that leads to ischemia, reduced blood flow, so that the heart can't function as well as it otherwise could.

So when this guy is jogging, because he has restricted blood supply because the heart is experiencing ischemia downstream from this stenosis, that's why there's heart failure so not able to deliver

It can also refer to the narrowing of any type of tubular structure, so if you have any type of pipe in a biological system, you can use stenosis there, but usually they're talking about a blood vessel.

Now if you have stenosis in one of your blood vessels, and it leads to ischemia then the muscles, and let's just say this a coronary artery here... the muscle cells over here are going to get less oxygen.

So, you can imagine that if we're really zoomed in on the surface of the heart and we're looking at the cardiac muscle tissue, if this person with this heart needed to go jogging and this cardiac muscle cell needed oxygen, they probably wouldn't be able to get the needed oxygen because of the stenosis which caused ischemia.