Morphologic characteristics of painful varicose veins in women: possible role of disordered collagen and endothelial cells

Objective

This study examines to what extent vein wall thickness, collagen arrangements, muscular layers distribution, immunohistochemical presentation of endothelial cell arrangement, and adventitia layer placement differed in patients with small painful veins vs large painful symptomatic varicose veins (VVs).

Methods

This study was conducted from June 2022 to September 2022 at Valley Vein Health Center, a rural phlebology outpatient clinic. Ten samples from each of the three subjects were collected (n = 3): five were small symptomatic veins, and five were large symptomatic veins. All tissue blocks were cut transversely, perpendicular to the vessel axis, into 5-μm-thick sections. Three stains were chosen: Masson trichrome, hematoxylin and eosin, and a cluster of differentiation 31 (CD31). Statistical analysis was performed with the GraphPad statistical program. Comparisons between vein wall thicknesses were made using Student’s t test.

Results

The average thickness of small veins was less than that of large veins (426 μm ± 26.1 μm vs 480 μm ± 19.2 μm, respectively; P < .001). Histologic and immunohistochemical (CD31) analysis of small symptomatic VVs by hematoxylin and eosin and trichrome stain showed an endothelial layer overlying the media, mostly of elastic tissue fibers, and smooth muscle bundles. CD31 expression analysis demonstrated more endothelial channels in the tunica media of the enlarged veins compared with smaller vessels. The larger vein’s microscopic structure was variable with irregular collagen arrangement, clumped elastin layer appearance, feathered muscular layer distribution, and thickened adventitia layer placement.

Conclusions

The morphological distinctions in VVs highlighted in this study need to be considered to develop potential drug therapies tailored to women.