Histological Appearance of Acute MIs

Question 1

Describe the Macroscopic and Microscopic changes up to 18 hours after the onset of symptoms?

Answer 1

NONE

Question 2

Describe the Macroscopic and Microscopic changes 24-48hrs after onset of symptoms

Answer 2

Macro- Pale, oedematous muscle.

Micro - Oedema, neutrophil infiltration and necrosis of myocytes.

Question 3

Describe the Macroscopic and Microscopic changes 3-4 days after onset of symptoms?

Answer 3

Macro - Yellow, rubbery centre with haemorrhagic boarder.

Micro - Obvious necrosis and inflammation (early granulation tissue)

Question 4

Describe the Macroscopic and Microscopic changes 1-3 weeks after onset of symptoms

Answer 4

Macro - Infarcted area paler and thinner

Micro - Granulation tissue then progressive fibrosis

Question 5

Describe the Macroscopic and Microscopic changes 3-6 weeks after onset of symptoms?

Answer 5

Macro - Silver scar becoming tough and white.

Micro - Dense fibrosis