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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Troponin-T is preferable to CPK-MB in the diagnosis of acute myocardial infraction in all the following situations except
assistant
The correct answer is  Ref Harrison 19 th ed pg 1594 Because of cardiac troponins are elevated for prolonged periods an episode of recurrent ischemia after four days would be more readily diagnosed with a marker that remains elevated in blood more briefly such as CK-MB which returns to normal levels by 72 hours .