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Duration of pharmacological thromboprophylaxis after outpatient endovenous laser ablation: a propensity score-matched analysis.

AIM OF THE STUDY
The objective of this study was to identify the optimal duration of pharmacological thromboprophylaxis after outpatient endovenous laser ablation (EVLA).


METHODS
In this multicentre retrospective study in a university hospital, regional hospital and private practices, we collected the demographic, procedural and outcome data of all consecutive patients with varicose veins class C2 to C6 undergoing outpatient EVLA of truncal and accessory veins between February 2009 and December 2015. The cumulative primary efficacy endpoint consisted of endovenous heat-induced thrombosis (EHIT) class 2–4, deep vein thrombosis (DVT) and pulmonary embolism (PE) diagnosed with duplex ultrasound or computed tomography angiography after 1 and 4 weeks of follow-up. Cumulative secondary endpoints were complete ablation of the treated veins and major bleeding, skin burns and infection.


RESULTS
A total of 864 patients were treated with EVLA as an outpatient procedure. Of those, 35 patients were omitted because of therapeutic anticoagulation or dual antiplatelet therapy. Another 36 cases were excluded as the patients received pharmacological thromboprophylaxis for 5 days. A total of 793 were included in the final analysis. Of those, 225 patients (28.4%) received fondaparinux 2.5 mg s.c. for 3 days, 166 patients (20.9%) received rivaroxaban 10 mg p.o. for 3 days and 402 patients (50.7%) received rivaroxaban 10 mg for 10 days. The incidence of EHIT class 2–4 was 0.8% (n = 6) in total, 1.3% (n = 6) in group 1 (treated for 3 days) and 0.3% (n = 1) in group 2 (treated for 10 days) (odds ratio [OR] 0.19, confidence interval [CI] 0.02–1.66, p = 0.133). The cumulative primary composite endpoint at 4-week follow-up was 1.1% (n = 9) and was 2.1% (n = 8) in group 1 and 0.3% (n = 1) in group 2 (OR 0.0.12, CI 0.01–0.96, p = 0.046). Propensity score-matched analysis revealed no significant difference in the composite primary endpoint (CI −0.074 to 0.26). Complete occlusion rate was 99.2% in group 1 and 98.8% in group 2 (OR 0.61, CI 0.15–2.59, p = 0.506). No PE or major bleeding events occurred in either group. Propensity score-matched analysis showed no significant difference in the secondary endpoints.


CONCLUSION
Using propensity score-matched analysis we showed that pharmacological thromboprophylaxis after EVLA seems to be equally effective with 3 days or 10 days of treatment with a similar success rate and safety profile. Undoubtedly, a large randomised control trial, ideally including a group without pharmacological thromboprophylaxis, is needed to draw more definitive conclusions on the optimal duration of pharmacological post-EVLA thromboprophylaxis.