The Proximity of Superficial Epigastric Vein to Saphenofemoral Junction is associated with Endovenous Heat-induced Thrombosis after Radiofrequency Ablation for Varicose Veins

ABSTRACT Objective To elucidate the risk factors of endovenous heat-induced thrombosis after radiofrequency ablation for varicose veins in association with the superficial epigastric vein position to the saphenofemoral junction. Methods We examined 125 legs from 218 patients (mean age, 67 years; 80 female legs) with great saphenous veins in association with the superficial epigastric vein proximity to the saphenofemoral junction using the duplex ultrasound test. According to the Clinical, Etiology, Anatomy and Pathophysiology classification (C1–C6), there were 62, 38, and 25 legs in the C2, C3, and C4–C6 categories, respectively. The postoperative duplex ultrasound tests, focused on endovenous heat-induced thrombosis, were conducted on days 1, 7, 30, and 90 after radiofrequency ablation. The endovenous heat-induced thrombosis analysis was based on Kabnick’s classification (class 1–4). We compared the great saphenous vein diameter and the superficial epigastric vein-saphenofemoral junction distance between the endovenous heat-induced thrombosis positive (N=32) and negative groups (N=93) using Student’s t-test. The risk factors (age >75, male sex, ≥C3 classification, adjunctive phlebectomy, prior venous surgery history, great saphenous vein diameter >7.5 mm, and short superficial epigastric vein-saphenofemoral junction distance [ Results The endovenous heat-induced thrombosis ratio after radiofrequency ablation was 25.6% (24, five, three, and no legs of class 1, 2, 3, and 4). In the endovenous heat-induced thrombosis positive group, the mean great saphenous vein diameter and the superficial epigastric vein-saphenofemoral junction distance were larger (8.0±2.3 vs. 6.4±2.0 mm, P 7.5 mm (οdds ratio, 3.50; P=0.003), and short superficial epigastric vein-saphenofemoral junction distance (οdds ratio, 2.92; P=0.01). Multiple logistic regression analysis showed that ≥C3 classification (οdds ratio, 3.39; 95% confidence interval, 1.30–8.86; P=0.013), great saphenous vein >7.5 mm (οdds ratio, 3.32; 95% confidence interval 1.33–8.25; P=0.010), and short superficial epigastric vein-saphenofemoral junction distance (οdds ratio, 2.71; 95% confidence interval, 1.09–6.71; P=0.032) were also significant risk factors. Conclusions Radiofrequency ablation treatment for patients with varicose veins should be considered postoperatively in combination with ≥C3 classification, great saphenous vein diameter >7.5 mm, and history of deep venous thrombosis and concomitant procedures, as it is related with higher chances of endovenous heat-induced thrombosis development.