Evolution of Morphologic Changes in MI Table

Question 1

occasionally dark mottling

Answer 1

4-12 hrs

Question 2

dark mottling

Answer 2

12-24 hrs

Question 3

mottling with yellow-tan infarct center

Answer 3

1-3 days

Question 4

Hyperemic border; central yellow-tan softening

Answer 4

3-7 days

Question 5

Maximally yellow-tan and soft, with depressed red-tan margins

Answer 5

7-10 days

Question 6

Red-gray depressed infarct

Answer 6

10-24 days

Question 7

gray-white scar, progressive from border toward core of infarct

Answer 7

2-8 wks

Question 8

scarring complete

Answer 8

> 2months

Question 9

usually none; variable waviness of fibers at border

Answer 9

1/2 - 4hr

Question 10

beginning coagulation necrosis; edema; hemorrhage

Answer 10

4-12 hr

Question 11

ongoing coagulation necrosis; pyknosis of nuclei; myocyte hypereosinophilia; marginal contraction band necrosis; beginning neutrophilic infiltrate

Answer 11

12-24 hr

Question 12

Coagulation necrosis, with loss of nuclei and striations; interstitial infiltrate of neutrophils

Answer 12

1-3 days

Question 13

beginning disintegration of dead myofibers, with dying neutrophils; early phagocytosis of dead cells by macrophages at infarct border

Answer 13

3-7 days

Question 14

Well-developed phagocytosis of dead cells; early formation of fibrovascular granulation tissue at margins

Answer 14

7-10 days

Question 15

Well-established granulation tissue with new bv and collagen deposition

Answer 15

10-14 days

Question 16

increased collagen deposition, with decreased cellularity

Answer 16

2-8 weeks

Question 17

Dense collagenous scar

Answer 17

> 2mo