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Updated: Aug 11, 2026
LAD-Ligation: A Murine Model of Myocardial Infarction
Published on: October 14, 2009
The healing of myocardial infarcts in man
Insights
This study examined 150 hearts after myocardial infarct, identifying three distinct forms of cardiac muscle necrosis. Findings reveal unique healing processes in different infarct zones, crucial for understanding heart attack recovery.
Area of Science:
- Cardiovascular Pathology
- Histology
- Myocardial Infarction Research
Background:
- Myocardial infarction (MI) leads to significant cardiac tissue damage.
- Understanding the morphological changes and healing processes post-MI is critical for clinical management.
Purpose of the Study:
- To characterize the distinct morphological patterns of myocardial necrosis following clinically proven myocardial infarcts.
- To elucidate the cellular mechanisms and stages of tissue repair in infarcted cardiac muscle.
Main Methods:
- Histopathological examination of 150 human hearts from patients deceased within 25 days of myocardial infarct onset.
- Morphological classification of myocardial necrosis into distinct forms based on tissue changes.
Main Results:
- Three distinct forms of myocardial necrosis were identified: coagulation necrosis, coagulative myocytolysis, and colliquative myocytolysis.
- Coagulation necrosis in central infarct zones involved macrophage absorption and fibroblastic collagenization without granulation tissue.
- Coagulative myocytolysis in outer infarct zones and non-infarcted myocardium showed acidophilic cells with myofibrillary damage.
- Colliquative myocytolysis, observed in large infarcts, affected subendocardial or perivascular cells, leading to edema and liquefaction.
Conclusions:
- Myocardial infarct healing involves distinct necrotic patterns and repair mechanisms depending on the infarct zone.
- The absence of granulation tissue in infarct repair highlights a unique healing pathway.
- Different forms of myocytolysis contribute to cardiac tissue remodeling after myocardial infarction.
Abstract:
One hundred and fifty hearts of patients who died within 25 days of the onset of a clinically proven myocardial infarct were examined. Three morphologically distinct forms of myocardial necrosis were recognized. In the central and median zones of an infarct the muscle showed coagulation necrosis. Subsequently the dead tissue was obsorbed by macrophages with the preservation of sarcolemmal sheaths. Then fibroblastic collagenization of the preserved stroma occurred. Repair was not achieved by granulation tissue. Coagulative myocytolysis occurred in the outer zone of an infarct and in the non-infarcted myocardium. The dead cells were acidophilic and showed myofibrillary damage characterized by anomalous cytoplasmic band formation. Breakdown of the fibres was followed by macrophage absorption and healing as in the central area of coagulation necrosis. Colliquative myocytolysis was seen in big infarcts. It affected a narrow band of myocardial cells in the subendocardial zone or surrounding blood vessels. The fibres became oedematous and seemed to liquefy.
