[Long-term remnants of coagulation necrosis of cardiomyocytes following myocardial infarction].
Remnants of cardiomyocytes showing coagulation necrosis in the scars caused by myocardial infarction were histopathologically studied. Among 305 autopsy cases of acute and/or healed myocardial infarction, 8 cases (7 men, 1 woman, ages 62 - 87 years, mean age 72.1) had masses of cardiomyocytes with coagulation necrosis at the center of the infarction scars more than 3 weeks (21 to 79 days) after the attack of myocardial infarction. All these cases had transmural infarction and more than 80% of the wall thickness of the left ventricle was involved in the infarction. No polymorphonuclear leukocytic infiltration or granulation tissue was found in the necrotic area, but macrophages were observed in the peripheral area adjacent to the scar tissue. Immunohistochemical staining for myoglobin showed no reaction in remnant necrotic cells or pericellular interstitium, which was similar to findings in the necrotic area more than 4 days after the infarction. These findings are important in the pathological diagnosis to distinguish remnant necrosis from acute necrosis, because 4 out of 8 present cases (50%) were misdiagnosed as acute myocardial infarction that superimposed on the previous old infarction.
Ohmori
Hiroko
H
Medical Student, Nippon Medical School, Japan.
Tamura
Koichi
K
Ono
Simpei
S
Ibi
Takayuki
T
Hashimoto
Satoshi
S
Sugisaki
Yuichi
Y
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology*; D009206:Myocardium / Q000473:pathology*; D009336:Necrosis