Smooth muscle differentiation in human vein wall at valvular level: Comparison with nonvalvular wall and correlation with venous function

The aim of this study was to evaluate local differences in smooth muscle di fferentiation in venous valves of patients suffering from chronic venous in sufficiency, in relation to functional hemodynamic parameters measured by e cho Doppler. These functional parameters did not correlate with smooth musc le differentiation at the valvular site. These results failed to support an initiating role of valvular structure in the development of chronic venous insufficiency. However, this work stresses differences in cellular differe ntiation of valve wall and nonvalvular smooth muscle cells in culture, and we found histologic differences in the structure of endovein and media (con nective tissue relative content) between valvular and nonvalvular venous wa ll. The presence of smooth muscle cells in the valve cusp was demonstrated by smooth muscle alpha-actin-specific labeling and was observed to be restr icted to one side of the valve cusp.