A STUDY OF THE MECHANISMS BY WHICH HEMODYNAMIC FUNCTION IMPROVES FOLLOWING LONG SAPHENOUS VEIN-SAVING SURGERY

Objective: To study the mechanisms by which haemodynamic function impr oves following long saphenous vein-saving surgery. Design: Cohort stud y. Patients: Twenty patients, 14 women and six men, with primary varic ose veins. Interventions: Varicose vein surgery by the long saphenous vein-saving technique. Main outcome measures: Preoperative investigati on by physical examination, strain-gauge plethysmography, phlebography and measurements of the long saphenous vein diameter at four differen t locations using high-resolution, real-time ultrasound. Three months following vein-saving surgery, the patients were reassessed with physi cal examination, strain-gauge plethysmography and measurements of the long saphenous vein diameter. Results: AU patients but one showed exce llent or good results following surgery. The preoperative diameter of the long saphenous vein was reduced by 40% at four different levels in the operated legs (p<0.01). The venous return time of the same legs i ncreased 2.4 times (p<0.001). The decrease of the long saphenous vein diameter correlated positively with the increase in venous return time (t-50), (r=0.50, p=0.04). Conclusion: The results suggest that the de velopment of incompetent perforators is an early major event in the fo rmation of primary varicose veins. The results also suggest that the l ong saphenous vein valvular incompetence in varicose veins is attribut able to venous wall dilatation rather than degeneration of the valves. The results support the hypothesis that the improvement in haemodynam ic function following long saphenous vein-saving surgery is due, at le ast partly, to a reduction of the long saphenous vein diameter, which in turn tends to restore valvular competence.