This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Irreversible injury to myocardium in MI occurs earliest by 
Select and explain. 
A. Few seconds, B. 10 minutes, C. 20 minutes, D. 40 minutes
C: 20 minutes
Answer: C: 20 minutes 
Explanation: Answer- C. 20 minuteshlyocardial function is more seflsith'e to kchemia (loss of contractility occurs within 60 seconds) than myocardial structure(irreversible injury occurs in 2O-40 minutes), thus myocardial necrosis begins at approximately 30 minutes after coronary occlusion