changes in MI

gross, survival time vs predominant finding
0-18 hrs- no change
18-24 hrs- vague pallor and softening
1-7 days- yellow pallor
7-14 days- central pallor with red border
months- white fibrous scar

microscopic, survival time vs predominant finding
1-4 hrs- wavy myocyte fibres
4-24 hrs- coagulative necrosis
1-4 days- neutrophilic infiltrate
4-7 days- macrophages
7-28 days- granulation tissue
months- fibrotic scar