Early Atherosclerotic Lesions in Sudden Infant Death Syndrome

pp 100-105

Abstract

Objective
The aim of the present study was to assess the morphology of early atherosclerotic lesions in coronary arteries from sudden infant death syndrome (SIDS) victims in order to recognize atherogenic mechanisms.

Material and Methods
We examined 52 victims of SIDS and 16 controls with known causes of infant death. The principal coronary arteries were serially cut and stained with hematoxilin-eosin, Azan, Alcian blue, acetic orcein, CD68, CD34 and á-SM actin, with subsequent histomorphometric analysis of the lesions.

Results
Preatherosclerotic lesions were found in 44.2% in SIDS group (23/52) and only in 6.3% in controls (1/16) (p=0.0062). Smooth muscle cells lost polarity, infiltrating the subedothelium, with rupture of the internal elastic membrane (IEM) in most cases. Angiogenesis was not observed. When muscular and elastic intimal thickening was present in the SIDS group, the results were as follows: neointimal thickness, 58.3±17.8 mm; affected perimeter of the IEM, 45.6%; area of neointimal proliferation, 0.03±0.01 mm2; and luminal area, 0.21±0.1 mm2 with a luminal stenosis of 13.8±5%.

Conclusions
Preatherosclerotic lesions develop early in SIDS victims, and they are significantly more frequent than in controls. Smooth muscle cells are fundamental in its genesis.