A patient who has been experiencing chest pain for several hours is admitted with a diagnosis of rule out acute myocardial infarction (AMI). Which laboratory test is most specific for the nurse to monitor in determining whether the patient has had an AMI?

Choice A rationale
Aortic regurgitation is a condition where the aortic valve doesn’t close tightly, causing blood to leak back into the left ventricle. This condition can lead to left heart failure but is not typically associated with right heart failure.
Choice B rationale
Mitral regurgitation is a disorder in which the mitral valve on the left side of the heart does not close properly. This condition can lead to left heart failure but is not typically associated with right heart failure.
Choice C rationale
Aortic stenosis is a narrowing of the aortic valve opening. This condition can lead to left heart failure but is not typically associated with right heart failure.
Choice D rationale
Tricuspid regurgitation is a disorder in which the heart’s tricuspid valve does not close properly, causing blood to flow backward into the right atrium. This condition can lead to right heart failure, especially when associated with pulmonary hypertension.

Choice A rationale
The need for Metoprolol (Lopresor) STAT does not necessarily indicate progression to septic shock. Metoprolol is a beta-blocker used to treat high blood pressure, heart failure, and angina. While it may be used in the management of sepsis to control heart rate, its use does not specifically indicate progression to septic shock.
Choice B rationale
The need for Norepinephrine to maintain a mean arterial pressure (MAP) greater than 65 mmHg despite fluid replacement is a strong indicator of septic shock. Norepinephrine is a vasopressor, a type of medication used to increase blood pressure. In septic shock, vasopressors are often required to maintain adequate blood pressure and organ perfusion despite aggressive fluid resuscitation.
Choice C rationale
A serum lactate level less than 2 mmol/L is generally not indicative of septic shock. Elevated lactate levels can indicate tissue hypoperfusion, a condition that may occur in septic shock. However, a level less than 2 mmol/L is typically considered within the normal range.
Choice D rationale
A blood pressure of 70/34 after the fluid bolus could indicate progression to septic shock. In septic shock, despite aggressive fluid resuscitation, blood pressure often remains dangerously low, which can lead to inadequate blood flow to the organs.