Proximal long saphenous vein valves in primary venous insufficiency. Histopathology and pathophysiological implications.

Objective: To verify some of the previous findings of venous valves describ ed in the literature, their pathophysiological significance and clinical im plications. Materials and methods: The elementary components of 65 proximal valves of t he long saphenous vein and their interrelationships were subjected to histo pathological examination. Valves were taken from patients subjected to long saphenous vein surgical removal for varicose veins of the lower limbs. Measurements and morphological evaluations were performed by optical micros copy. Results: The valvular sinus, agger and proximal portion of the cusp underwe nt parallel variations of thickness. Thickening of the proximal portion of cusp was related to increase in smoot h muscle cells in the agger and to elastic layer dissociation. Thickening of the distal portion of cusp depended on the collagen component ; sometimes it was shortened, crumpled and led to the formation of a thicke ned border. The vein wall in a commissural aneurysm was usually thinner tha n in the valvular sinus. Alterations in the intima, in the elastic membrane and in the media were found in the 98% of the valvular annulus. Ectasis an d asymmetry of the venous wall were mainly related to the muscular hypoplas ia of the media. Conclusions: The development of primary venous insufficiency seems to be du e to the following tissue alterations: dilatation of the valvular annulus a nd hypotrophy of the cusp. The hemodynamic mechanical injury increases the tissue damages of both annulus and cusps. This pathophysiologic interpretat ion of venous insufficiency suggests the need for detailed diagnostic proce dures before reparative surgery of valves.