Which laboratory finding is most consistent with cardiogenic shock secondary to myocardial infarction?

Which laboratory finding is most consistent with cardiogenic shock secondary to myocardial infarction?

• A. Decreased troponin
• B. Elevated troponin and BNP
• C. Decreased CK-MB
• D. Normal troponin

Answer: (B)

When a myocardial infarction leads to cardiogenic shock, labs reflect both myocardial injury and the heart’s failing pump. Troponin rises when heart muscle is damaged, so elevated troponin is expected after an MI. BNP is released in response to increased ventricular wall stress from poor pumping and elevated filling pressures; in cardiogenic shock the ventricle is under heavy strain, so BNP levels rise too. Seeing both elevated troponin and BNP best fits the picture of an infarct causing severe cardiac pump failure. A normal or decreased troponin wouldn’t indicate active myocardial injury, and decreased CK-MB doesn’t align with the typical injury pattern seen in MI.

When a myocardial infarction leads to cardiogenic shock, labs reflect both myocardial injury and the heart’s failing pump. Troponin rises when heart muscle is damaged, so elevated troponin is expected after an MI. BNP is released in response to increased ventricular wall stress from poor pumping and elevated filling pressures; in cardiogenic shock the ventricle is under heavy strain, so BNP levels rise too. Seeing both elevated troponin and BNP best fits the picture of an infarct causing severe cardiac pump failure. A normal or decreased troponin wouldn’t indicate active myocardial injury, and decreased CK-MB doesn’t align with the typical injury pattern seen in MI.