Caution: Paralyzing Agent
Agree that there are multiple advantageous effects of NTG outside of pain relief in the setting of myocardial ischemia. Not the least of which is preservation of the hypokinetic RV in the context of relative or actual pulmonary hypertension. If you can keep the RV sending blood to the LV you've won more than half the battle.I disagree with this. Theoretically, nitro is given to vasodilate the coronary arteries to improve blood-flow to an area of the heart which is hypoxic due to a spasm or blockage. The indication for giving nitro, then, is that you feel your patient is having a an event related to hypoxic cardiac tissue.
This is why my side-bar question earlier in the thread becomes pertinent, which is "what is the actual etiology of chest pain". As of my last research on the topic, no one base been able to definitively say why hypoxic cardiac tissue leads to pain. Ultimately, this leads into why some people can be having significant cardiac events without associated chest pain.
Whether you believe nitro is helpful, harmful, or a non factor in cardiac events is a slightly different topic, although I will again mention that there are studies in both directions on this topic.