Comparison of the endothelial surface and subjacent elastic lamina of anterior descending coronary arteries at the location of atheromatous lesions with internal thoracic arteries of the same subjects: a scanning electron microscopic study.
OBJECTIVE
Current theories fail to explain the localisation of atheromatous lesions or their variable incidence in different arteries of the same subject. The objective of this study was to compare by scanning electron microscopy (SEM) the endothelial surface and the subjacent elastic lamina of human coronary arteries at the location of areas showing infiltration by lipid and cells, with the same components of internal thoracic arteries of the same subjects.


METHODS
The endothelial surface and the subjacent elastic lamina of localised atheromatous areas of 146 anterior descending coronary arteries were compared with the same structural components of the internal thoracic arteries of the same subjects, using SEM, transverse paraffin sections and freeze-fracture. Some arteries were digested with formic acid to destroy the endothelium and interstitial tissue, and reveal the elastin fibre structure of the elastic laminae.


RESULTS
Coronary arteries showed localised defects of the endothelial surface and of the elastin fibre structure of the subjacent elastic membrane, with the presence of lipid and cells in transverse sections of the intima. Internal thoracic arteries showed such changes only rarely, more particularly in older age groups.


CONCLUSIONS
In localised areas of the coronary arteries showing infiltration of the wall by lipid and cells, there were imperfections of the endothelial surface and of the elastin fibre structure of the subjacent elastic lamina. These imperfections were not in general present in the endothelial surface, or subendothelial elastic lamina of the internal thoracic arteries in age groups below 50, and only rarely in older subjects.
Sims
Frank Harding
FH
Department of Pathology, School of Medicine, University of Auckland, New Zealand.
Gavin
John Bevan
JB
Edgar
Stephen
S
Koelmeyer
Timothy D
TD
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003324:Coronary Artery Disease / Q000473:pathology*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D004547:Elastic Tissue / Q000648:ultrastructure; D005614:Freeze Fracturing; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D017539:Tunica Intima / Q000648:ultrastructure*; D014463:Ultrasonography