Histopathological finding 12 hours after ischemic injury to hea is?
High-Yield Explanation
Ischemic injury to hea is Myocardial infarction Earliest change seen is waviness of fibers . - early coagulation necrosis - pyknosis of nucleus Myocyte hyper-eosinophilia Early neutrophilic infiltrate Marginal contraction bank necrosis 1-3 days - brisk interstitial infiltrate of neutrophils 3-7 days - early phagocytosis of dead cells by macrophages at infarct border. Note: best enzyme for diagnosis of MI is Troponin I . TIME MICROSCOPIC CHANGES GROSS CHANGES 0 - 1/2 hrs - - 1/2 - 4 hrs Waviness of fibers of the border - 4 - 12 hrs Early coagulation necrosis, edema and hemorhage Dark mottling 12 - 24 hrs Coagulation necrosis with neutrophilic infiltration Dark mottling 1 - 3 days Coagulation necrosis with loss of nuclei and striations. Interstitial infiltrate of neutrophils Mottling with yellow - fan infact center 3 - 7 days Beginning of disintegration of dead myofibres with dying neutrophils. Early phagocytosis of dead cells by macrophages Hyperemic border, and central yellow fan softening 7 - 10 days Well developed phagocytosis of dead cells. Granulation tissue of margins Maximally yellow fan and soft, with depressed red-fan margins 10-14 days Well - established granulation tissue with new blood vessels and collagen deposition Red-gray depressed infarct borders 2 - 8 week Increased collagen deposition, with decreased cellularity Grey-white scar, progressive from border foward core of infarct > 2 month Dense collogenous scar Scarring complete