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
Calcium channel blockers are primarily used to treat hypertension, angina, and certain heart arrhythmias. They work by relaxing the muscles of your heart and blood vessels. While they can affect heart rate and blood pressure, they would not typically have immediate implications for a patient presenting with intermittent chest pain.
Choice B rationale
Phosphodiesterase 5 enzyme inhibitors, such as sildenafil (Viagra), are used to treat erectile dysfunction and pulmonary arterial hypertension. These medications can interact with nitroglycerin, a common medication used to treat chest pain, to cause a severe and life-threatening drop in blood pressure. Therefore, it’s crucial to know if a patient is taking this type of medication when they present with chest pain.
Choice C rationale
Anticoagulants are used to prevent blood clots. If a patient is taking an anticoagulant, it could affect their clotting times and could be important if the patient needs surgery or if the cause of their chest pain is a clot. However, this would not typically have immediate implications for the treatment of chest pain.
Choice D rationale
Loop diuretics are strong diuretics that are used to treat edema and hypertension. They work by preventing your body from absorbing too much salt, allowing the salt to instead be passed in your urine. While important to know for overall patient care, they would not typically have immediate implications for a patient presenting with chest pain.

Choice A rationale
Sinus tachycardia at a rate of 110 beats/min is a normal response to exercise. During a stress test, the heart rate will naturally increase as the body’s demand for oxygen increases. A heart rate of 110 beats/min is within the expected range during moderate exercise.
Choice B rationale
An increase in blood pressure from 134/68 to 150/80 mm Hg is a normal response to exercise. During a stress test, blood pressure will naturally rise as the heart works harder to pump blood to the muscles. This increase is within the expected range during moderate exercise.
Choice C rationale
Feeling tired during a stress test on a treadmill is a normal response to exercise. Fatigue can occur as the body’s energy stores are used up during physical activity. However, if the patient reports extreme fatigue or other symptoms such as chest pain or shortness of breath, it may indicate a problem.
Choice D rationale
Inversion of T waves on the electrocardiogram during a stress test is a sign of myocardial ischemia, a condition in which the heart muscle is not getting enough oxygen. This could indicate the presence of significant coronary artery disease and is a finding that would necessitate immediate action.