Determining Risk Factors for Endovenous Heat-induced Thrombosis after Radiofrequency Ablation

The objective of this study was to evaluate risk factors, incidence, management, and outcome of endovenous heat-induced thrombosis (EHIT) related to radiofrequency ablation (RFA).

This was a single-center retrospective analysis of patients over the age of 18 who underwent RFA between 2016 and 2019. Demographics, comorbidities, medications, severity scores, vascular anatomy, procedural details, and outcome data were collected. EHIT-related data included occurrence, grade, laterality, management, and outcome.

During the study period, 672 RFA procedures were performed at our institution. Of these, 642 (median age 57 (21-93), 62.3% female) met study inclusion criteria. EHIT was observed in 43 (6.6%) cases. Concurrent left common femoral vein (CFV) or right femoral vein (FV) incompetence was found to be more prevalent in the EHIT group (P = 0.024 and P = 0.011, respectively). Compared with performing RFA alone, concurrent performance of stab phlebectomy and sclerotherapy with RFA on the left side was found to be associated with possible increased risk for EHIT (P = 0.021). Furthermore, patients with diabetes mellitus (DM) (P = 0.05) and those with median diameter of the treated left vein of 1.2 cm (P = 0.02) were more likely to have a higher EHIT grade (III and IV) than those without DM and those with smaller vein diameter, respectively. Management included aspirin (44%), anticoagulant (28%), both (10%), or neither (18%). EHIT either resolved or regressed (64%), did not change (5%), or propagated (8%) at follow-up.

Left CFV or right FV incompetence was found to be more prevalent in the total EHIT group. Furthermore, DM and the median size of the treated vein on the left (1.2 cm) were more prevalent in the high (III-IV) versus low grade (I-II) EHIT group. More than 50% of EHIT improved (regressed or resolved) at follow-up regardless of the management option. Further analysis with larger patient samples are needed to confirm the association between these variables and the development of EHIT.