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Ultrasonography in Saphenous Vein Conduit Selection

Objective There are anatomic, histologic, and physiologic differences between great saphenous veins (GSVs) and accessory saphenous veins (ASVs). The GSV is deep to the saphenous fascia. ASVs are superficial to this layer and have thin walls with diminished muscle cells and elastic fiber. This study reviews the ultrasound characteristics of these veins, changes associated with varicose vein disease, and venous anomalies that impact on saphenous vein conduit selection. Methods Intraoperative ultrasound studies were performed before coronary artery bypass surgery in 83 patients without known venous disease, in 25 limbs with telangiectases, and in 25 limbs with varicosities. Vein characteristics and segment caliber in the proximal and distal thigh and calf were recorded. Results GSV segments of caliber and length suitable for use as coronary artery conduits are more common in men than women in the distal thigh (70% vs. 50%, p = 0.037), proximal calf (68% vs. 40%, p = 0.005), and distal calf (88% vs. 70%, p = 0.017). Dilated GSV segments are identified in 5% of normal limb segments, 21% in limbs with telangiectases (p < 0.001), and 22% in limbs with varicosities (p < 0.001). The incidence of absent or hypoplastic GSV segments is increased in limbs with varicosities compared with normal limbs (33% vs. 21%, p = 0.006). Conclusions GSVs are not uniform in caliber and gender differences are present. GSVs in limbs with telangiectases and varicosities have an increase in dilated and hypoplastic vein segments. Intraoperative ultrasound studies identify GSV segments for use as coronary conduits, avoiding ASVs and abnormal venous structures.