Alan:
I was one of first paramedics in MO 30 years ago, then worked as an ER and ICU RN. I am currently a board certified Internist and Cardiologist. I also spent short stints as a Deputy Sheriff and Firefighter. I treat MIs on a nearly daily basis.

I was trying to provide a limited response to a question. Historically the impact of NTG, and to a lesser extent O2, has been dramatically lessened with improving therapy. That doesn’t mean they have no place in treatment, but that priorities have changed. Often in the throes of an MI patients are hemodynamically unstable. If I have a limited amount of BP “to work with”, I would rather use it up by giving beta-blockers rather than NTG. More “bang for the buck” so to speak.

Current therapy for MI is complex and fluid.
I would refer you to the American College of Cardiology site for detailed treatment recommendations and rationale: http://www.acc.org/qualityandscience/clinical/topic/topic.htm . Look to these sections relative to this discussion:

ST-Elevation Myocardial Infarction: ACC/AHA Guidelines for the management of Patients With

Unstable Angina/Non-ST-Elevation Myocardial Infarction: ACC/AHA 2007 Guidelines for the Management of Patients With

Edit:
At the risk of beating a dead horse. Additional info on MI treatment priorities:

http://www.acc.org/qualityandscience/clinical/measures/stemi/pdfs/STEMIfinal.pdf
http://www.acc.org/qualityandscience/clinical/measures/stemi/pdfs/EditorialFinal.pdf


http://www.acc.org/qualityandscience/cli...isory040105.pdf
http://www.acc.org/qualityandscience/clinical/practice_advisory/pdfs/COMMITBetaBlockerFACTSheet.pdf