Prospective Randomized Trial of Anti-Thrombotic Strategies Following Great Saphenous Vein Ablation Using Injectable Polidocanol Endovenous Microfoam (Varithena™).

OBJECTIVE: Post-ablation deep vein thrombosis (DVT) represents a potentially serious complication following Varithena™ polidocanol endovenous microfoam (PEM) ablation. The following primary outcomes were assessed: Whether (1) adjunctive Apixaban anticoagulation or (2) mechanical DVS saline flushing could reduce SFJ thrombus extension (PASTE) and/or DVT compared with compression alone, following GSV PEM ablation.

METHODS: Varithena™ 1% PEM ablation patients were randomized to: 1) SFJ compression, 2) Compression and DVS saline flushing, or 3) Compression, DVS saline flushing, and 5 days post-procedural 5mg BID oral Apixaban anticoagulation. Duplex imaging was obtained 7-10 days post-PEM ablation and PASTE/DVT incidence (primary endpoint) was compared between groups at this time point.

RESULTS: 304 limbs in 257 patients were treated with PEM. 103 limbs received SFJ compression (Group C, 33.8%), 101 received compression and deep venous flushing (Group D, 32.9%), and 100 received compression, deep flush, and anticoagulation (Group A, 33.2%). Mean ultrasound follow-up time was 9.7 days (all patients) with primary GSV closure rate of 92.4%. SFJ PASTE (II-IV) occurred in 0.9%, 1.0%, and 0% (groups C, D, and A, respectively). DVT occurred in 16.7%, 14.7%, and 1.98% (groups C, D, and A, chi-square, p = 0.002). Group A patients receiving apixaban anticoagulation had significant reduction in DVT compared with Group C (1.98% vs 16.7%, chi square, p < 0.001); likewise, Group A patients had significantly reduced DVT occurrence compared with Group D (14.7% vs. 1.98%, chi square p = 0.00162) while Groups C and D were not statistically different (16.7% vs 14.7%, chi-square, p = 0.60).

CONCLUSIONS: (1) Neither adjunctive DVS flushing, nor anticoagulation reduced clinically relevant SFJ PASTE (II-IV) incidence, which remained similarly low across all groups and ranged between 0%-1% regardless of adjunctive DVS flushing or anticoagulation. This was significantly lower than prior reports (2.3%-4.1%). (2) DVS flushing had no influence on the rate of DVT. Observed PEM-induced DVT incidence using SFJ compression alone or compression with DVS flushing (16.7% and 14.7%, respectively) was significantly higher than prior reports (2.5%-9.6%). This may relate to the greater extent of AK/BK GSV territory treated in the present study. (3) 5 days post-procedural 5mg BID oral Apixaban anticoagulation significantly reduced DVT occurrence to 1.98%, compared with non-anticoagulated patients (16.7%). This is comparable to DVT rates reported after EVTA (0.7-1.7%). (4) Postprocedural apixaban anticoagulation may have a significant preventive role in reducing DVT occurrence after PEM ablation.