Pacing definitely alters the ability to assess RWMA (makes it more difficult. But not impossible), though you have an expected pattern in many/most RV paced patients. Should see septal contraction, followed by the rest of the LV. Sometimes their conduction system is very fast and the difference is negligible, but I have seen some that were VERY distinct.
If there is ischemia of a major coronary artery, you should still be able to see RWMA (unless the only vessel affected is the branch to the AV node). Myocardium should still be thickening. The LV cavity should still be collapsing during systole. If those things aren't happening, I'd be looking very closely at all the different segments of the LV.
