Healed MI (myocyte hyper)
Slide #8
This slide comes from the post-mortem of the 56-year-old man described in slide #2. He had had multiple previous myocardial infarctions and was known to have multi-vessel coronary atherosclerosis, S/P bypass. At autopsy, there were multiple pale white-grey regions consistent with scars.
Broad, perivascular regions of fibrosis have replaced myocardium. The longitudinally-cut residual, viable myocytes show hypertrophy, characterised by fiber thickening and change of the nuclei from spindle - or cigar shaped - to "box car" like (rectangular). The fibrous tissue shows relatively few spindle cell nuclei of fibroblasts and large masses of pink collagen fibers.
Checklist: Have you identified
- boxcar nuclei in hypertrophied myocytes
- collagen fibers
- nuclei of fibroblasts