Factors associated with ablation-related thrombus extension following microfoam versus radiofrequency saphenous vein closure

Objective: Polidocanol endovenous microfoam ablation (MFA) is approved by the US Food and Drug Administration for great saphenous vein (GSV) closure, yet there are few published data on the subsequent risk of ablation-related thrombus extension (ARTE). Recent societal practice guidelines recommend against routine postprocedure duplex ultrasound (DU) examination after thermal ablation of the GSV in asymptomatic patients. At present, limited data do not allow this recommendation to extend to MFA. Our aim is to identify characteristics and outcomes associated with ARTE following MFA vs radiofrequency ablation (RFA).

Methods: A retrospective review of a prospectively maintained database was conducted of patients who underwent MFA and RFA closure of incompetent above-knee GSVs. Patients treated for isolated tributary vein treatment or did not have a postprocedure DU examination within 48 to 72 hours were not included. Patients were classified into two groups: ARTE and no ARTE. Demographic data, Clinical, Etiologic, Anatomic and Pathophysiologic class, Venous Clinical Severity Score, operative details, postprocedure (48-72 hours) DU findings, and adverse events were analyzed. Variables that were significant on univariate analysis were evaluated using multivariate logistic regression with the primary outcome being development of ARTE.

Results: Between June 2018 and February 2023, 800 limbs were treated with either MFA (n = 224) or RFA (n = 576). Ninety-six GSVs treated with MFA met the study criteria. One hundred fifty successive GSVs treated with RFA during the same period were included as a comparison group. There was no statistically significant difference in baseline demographics between the two groups. Six patients (2.4%) demonstrated ARTE on postoperative DU examination at 48 to 72 hours (MFA, n = 5 [5.2%]; RFA, n = 1 [0.7%]; P = .02). Saphenous vein ablation with MFA (P = .045) and a vein diameter of >10 mm (P = .017) were associated with ARTE on both univariable and multivariable analysis. All patients who developed ARTE were treated with oral anticoagulants (mean, 15.6 days). Body mass index, Clinical, Etiologic, Anatomic and Pathophysiologic class, Venous Clinical Severity Score, microfoam volume, operative time, and prior deep venous thrombosis were not predictive of ARTE.

Conclusions: ARTE after above-knee GSV closure occurred more frequently after MFA. Our results suggest that a saphenous vein diameter of >10 mm may be associated with ARTE. Despite this finding, all patients with ARTE were treated with short-term anticoagulation with no related complications. Until larger studies with high-risk subgroups have been studied after MFA, DU examination should be performed routinely after this procedure and patients with ARTE anticoagulated until the thrombus retracts caudal to the saphenofemoral junction or is no longer present on DU examination. Current societal guidelines recommending against routine post-thermal ablation DU examination should not be applied to similar patients after saphenous nonthermal MFA ablation.