ObjectiveThe optimal ablation distance from the catheter tip to the common femoral vein during endovenous laser ablation (EVLA) of the great saphenous vein (GSV) is a matter of debate. In this study, we evaluated the feasibility and safety of flush ablation (fEVLA) of the GSV. MethodsThis single-center, retrospective analysis of prospectively collected data included all consecutive fEVLA interventions of the GSV between September 2017 and October 2018. Interventions were performed with a 1470-nm radially emitting fiber. Primary end points were technical feasibility of fEVLA and endovenous heat-induced thrombosis (EHIT) class 2 to class 4. Secondary end points were procedure-related complications; anatomic success at week 6; and flush occlusion at day 1, day 10, and week 6. ResultsA total of 135 consecutive intended fEVLA procedures were performed in 113 patients (86 female, 27 male). The average body mass index was 24.9 ± 4.3 kg/m2. The Clinical, Etiology, Anatomy, and Pathophysiology (CEAP) clinical class for these patients was C2 in 78 (57.8%), C3 in 48 (35.6%), C4 in 8 (5.9%), and C5 in 1 (0.7%). The GSV diameter at the saphenofemoral junction was 9.4 ± 2.7 mm with a maximum of 16 mm. In 126 cases (93.3%), concomitant treatment of tributaries with phlebectomy or foam sclerotherapy was performed. In 127 cases (94.1%), fEVLA was technically feasible; in 8 cases (5.9%), appropriate catheter tip placement was not possible. In these cases, “standard” GSV ablation 10 to 20 mm distal to the saphenofemoral junction was performed. In the remaining 127 cases, one (0.8%) EHIT class 2 and one (0.8%) EHIT class 3 developed at day 10. After a 2- to 3-week course of anticoagulation with rivaroxaban, these EHIT cases resolved without sequelae. Furthermore, one (0.8%) superficial vein thrombosis and one (0.8%) calf vein thrombosis at the site of phlebectomy were observed. No local groin complication occurred. Flush occlusion was observed in 94.5%, 95.3%, and 88.2% of the cases at day 1, day 10, and week 6, respectively. Multivariate regression analysis revealed no significant association between flush ablation at day 1 and age, body mass index, CEAP class, fiber type, maximum vein diameter, or applied joules per centimeter. ConclusionsThe results of this study suggest that fEVLA of the GSV using a radial emitting laser is feasible and seems to be safe.