When we do a 12-lead and have inferior involvement, the directive states that we assume there is right sided ventricular MI and must confirm with V4R, and then states we should never give nitro for right sided ventricular STEMI. All of that is clear, but what I am wondering is that if the V4R is negative, does that clear the pt for Nitroglycerin use for the inferior STEMI, or does that simply help confirm the STEMI for the emergency department? Thanks.