Great saphenous vein patency and endovenous heat-induced thrombosis after endovenous thermal ablation with modified catheter tip positioning

Abstract

Thrombus extension into a deep vein after superficial venous thermoablation remains a unique complication in the treatment of superficial reflux disease of the great saphenous vein (GSV). In this study, we evaluate if catheter tip positioning or vein diameter correlate with the length of proximal patent segment of GSV after ablation and more caudal catheter positioning decreases the incidence of proximal thrombus extension into the femoral vein. This was a prospective study conducted from January 2008 to November 2009 of 73 patients undergoing radiofrequency ablation (RFA). Preoperative, intraoperative, and postoperative duplex ultrasound scans were obtained using standard protocols to establish reflux and target vein diameter. Intraoperative measurements were performed from the catheter tip to the femoral vein margin. Duplex ultrasound studies were obtained between 5 and 7 days after the procedure, with 1-month follow-up. The relationship between catheter tip positioning and vein diameter with the length of the proximal patent GSV segment after ablation and the incidence of proximal thrombus extension were analyzed. RFA was performed in 73 patients. Intraoperatively, the mean catheter tip positioning distance was 2.75 cm (range, 2.4-3.0 cm) from the saphenofemoral junction (SFJ), with 93% of the catheters placed within 2.6 to 2.9 cm of the femoral vein. The GSV mean diameter at the SFJ was 0.90 cm (range, 0.37-1.88 cm). After RFA, all GSVs were occluded, with a mean residual patent proximal GSV length of 1.17 cm (range, 0.3-10 cm). Two patients demonstrated thrombus extension from the SFJ into the femoral vein for a 2.7% incidence of endovenous heat-induced thrombosis. In patients undergoing RFA for saphenous reflux, neither catheter tip positioning nor vein diameter correlates with the length of the proximal patent segment of GSV after ablation. In addition, catheter positioning does not decrease the incidence of proximal thrombus extension into the femoral vein.