📌 𝐅𝐨𝐥𝐥𝐨𝐰 𝐨𝐧 𝐈𝐧𝐬𝐭𝐚𝐠𝐫𝐚𝐦:- [ Ссылка ]
📌𝗝𝗼𝗶𝗻 𝗢𝘂𝗿 𝗧𝗲𝗹𝗲𝗴𝗿𝗮𝗺 𝗖𝗵𝗮𝗻𝗻𝗲𝗹 𝗛𝗲𝗿𝗲:- [ Ссылка ]
📌𝗦𝘂𝗯𝘀𝗰𝗿𝗶𝗯𝗲 𝗧𝗼 𝗠𝘆 𝗠𝗮𝗶𝗹𝗶𝗻𝗴 𝗟𝗶𝘀𝘁:- [ Ссылка ]
Acute myocardial infarction (MI) indicates irreversible myocardial injury resulting in necrosis of a significant portion of myocardium (generally more than1 cm). The term "acute" denotes infarction less than 3-5 days old when the inflammatory infiltrate is primarily neutrophilic. Acute MI may be either of the nonreperfusion types, in which case the obstruction to blood flow is permanent, or of the reperfusion type, in which the obstruction or lack of blood flow is long enough in duration (generally hours) but is reversed or restored after myocardial cell death occurs.
Gross Features
Sequence:
------------------
18-24 hours - myocardial pallor.
1-3 days - pallor, moderate hyperemia (redness due to congestion with blood).
3-7 days - yellow lesion with hyperemic border.
10-21 days - maximally yellow.
6 weeks - white (fibrosis).
Microscopic Features
Sequence:
-----------------
1-3 hours - Wavy (myocardial) fibers
4-12 hours - Coagulative necrosis & loss of cross striations, contraction bands, edema, hemorrhage, PMN infiltrate.
18-24 hours - Coagulative necrosis, pyknosis of nuclei, and marginal contraction bands.
1-3 days - Loss of nuclei (karyolysis), loss of striations, abundant PMNs.
3-7 days - Macrophage and mononuclear infiltration, fibrovascular response.
10-21 days - Fibrovascular response, prominent granulation tissue.
6 weeks - Fibrosis.
#cardiovascularPathology #AcuteMyocardialInfarction #usmlevideos #usmlestep1videos #pathologyvideos #pathovideos #animatedvideolectures #pathoanimatedvideos #animatedpathologyvideos #usmle #drgbhanuprakash
