PN Adult Medical Surgical Practice Exam

Which laboratory result indicates that a client is experiencing a myocardial infarction?

1. Decreased lipase

2. Decreased erythrocyte sedimentation rate (ESR)

3. Elevated creatinine

4. Elevated troponin

The correct answer is: Elevated troponin

The presence of elevated troponin levels is a significant indicator of myocardial infarction (MI) because troponin is a protein found in cardiac muscle that is released into the bloodstream when there is damage to the heart muscle. In the context of an MI, when the heart muscle is injured due to inadequate blood supply, troponin levels increase, reflecting the extent of the damage. Therefore, measuring troponin is a critical component in the diagnosis of MI, as high levels can confirm the event, guide treatment, and suggest prognosis. In contrast, decreased lipase is more closely associated with pancreatic issues rather than heart-related conditions. Decreased ESR does not indicate a myocardial infarction; rather, it reflects inflammation in the body and can be altered in various conditions, but it is not specific to heart problems. Elevated creatinine is typically related to kidney function and does not provide direct insight into myocardial status. Thus, elevated troponin is the most definitive laboratory result for diagnosing a myocardial infarction.