I look at it like this...
Hyperlipidemia, smokung, genetics cause CAD. When the CAD gets bad enough before intervention, and the Coronary arteries become occluded causing ischemia to the heart muscle usually angina present, or other symptoms such as diaphoretic, arm pain etc..
I associate Acute MI with Acute Coronary Syndrome
I consider CAD to be chronic. ACS is acute (it's in the name): acute MI/STEMI/NSTEMI. Our facility usually reserves that term for STEMI, not NSTEMI, though I can't really say why. We don't use it very often anyway, we jsut say what happened.