Improvements of venous tone with pycnogenol in chronic venous insufficiency: an ex vivo study on venous segments.

This study evaluated the stretching and dilatation of venous segments ex vivo in subjects with primary varicose veins in comparison with comparable segments from subjects that used the supplement Pycnogenol (150 mg/d) for 3 months before surgery. Subjects with varicose veins and chronic venous insufficiency voluntarily used Pycnogenol for a period of at least 3 months. The segments of veins removed with surgery (in 30 subjects that had used Pycnogenol and in 10 comparable control subjects that had not used the supplement) were compared with normal, unused vein segments harvested for bypass grafting. The segments were suspended and a weight was attached to the distal part of the veins for 3 minutes and dilated with pressurized water. Digital images were recorded; the veins were measured before and after stretching to evaluate elongation. The manipulation of the vein segment was minimal. Tests were completed within 20 minutes after harvesting the veins. All segments were 4 cm long. The stretching test indicated a significantly higher level of passive elongation in control, varicose segments (2.29; 0.65 mm) in comparison with 1.39; 0.2 mm in vein segments from Pycnogenol-using patients. The dilation test showed an average higher dilation (2.19; 0.3 mm) in control varicose veins in comparison with varicose veins from Pycnogenol-using patients (1.32; 0.7 mm) (p < 0.05). Stretching and dilatation were lower in veins from Pycnogenol-using subjects (p < 0.05). The measurement of destretching and the recovery after dilatation indicated a better tone and recovery of the original size/shape in varicose segments from patients using Pycnogenol. Varicose segments had a more significant persistent dilatation and elongation in comparison with normal vein segments. Pycnogenol seems to decrease passive dilatation and stretching and gives vein walls a greater tonic recovery and elasticity that allows the vein to recover its original shape after dynamic stresses.