Registered Nurse Here; Okay now i"m not sure I understand your question. I believe your asking how a MI is diagnosed and the nursing measures for MI. Hope this is correct, 1.) A myocardial infraction can be diagnosed in several ways, a 12 lead EKG, Cardiac Enzymes, Sonogram, balloon pump under fluorescent lighting, (of a x-ray machine). The nursing care, is to relieve as much oxygen requirement as possible to the heart. For instance: No execration, bathing patient so they do use extra O2 and strain the heart more, bed rest, pain medication. Basically be supportive, administrator medications as ordered by your physician, and relieve the heart of as much work as possible. Collateral circulation, this is where blood vessels, create a network and work around the myocardial infraction which is dead muscle tissue. The collateral circulation is done by the body and begins immediately with blood vessel network, to work around necrotic tissue damage. The human body can be an amazing mystery.