Summary:Background: The invasive management of varicose veins has a known risk of post-operative deep venous thrombosis and subsequent pulmonary embolism. The aim of this study was to evaluate absolute and relative risk of venous thromboembolism (VTE) following commonly used varicose vein procedures. Patients and methods: A retrospective analysis of secondary data using Hospital Episode Statistics database was performed for all varicose vein procedures performed between 2003 and 2013 and all readmissions for VTE in the same patients within 30 days, 90 days, and one year. Comparison of the incidence of VTEs between procedures was performed using a Pearson's Chi-squared test. Results: In total, 261,169 varicose vein procedures were performed during the period studied. There were 686 VTEs recorded at 30 days (0.26 % incidence), 884 at 90 days (0.34 % incidence), and 1,246 at one year (0.48 % incidence). The VTE incidence for different procedures was between 0.15-0.35 % at 30 days, 0.26-0.50 % at 90 days, and 0.46-0.58 % at one year. At 30 days there was a signifi cantly lower incidence of VTEs for foam sclerotherapy compared to other procedures (p = 0.01). There was no difference in VTE incidence between procedures at 90 days (p = 0.13) or one year (p = 0.16). Conclusions: Patients undergoing varicose vein procedures have a small but appreciable increased risk of VTE compared to the general population, with the effect persisting at one year. Foam sclerotherapy had a lower incidence of VTE compared to other procedures at 30 days, but this effect did not persist at 90 days or at one year. There was no other signifi cant difference in the incidence of VTE between open, endovenous, and foam sclerotherapy treatments.
Keywords: Varicose veins, vascular surgical procedures, thrombosis, embolusThe wide range of reported incidences may be accounted for by the varying length of follow-ups in the studies and by whether routine duplex scanning was performed postoperatively or it was relied upon the development of clinical features of a DVT. The signifi cance of duplex identifi ed DVTs in the absence of clinical signs is uncertain; however, one series examining this problem reported no instances of a patients with early positive duplex fi ndings developing a clinical DVT on long term follow-up [3].The relative risk of DVT following diff erent VV procedures is currently unknown. NICE guidelines have highlighted the lack of large cohorts and high quality evidence, investigating this phenomenon, as the available evidence is limited to comparisons between two procedure types, with relatively small cohorts leading to identifi cation of sporadic events, which preclude in-depth statistical analysis. Currently the only reported comparisons are the ones between RFA and EVLA, which demonstrate no signifi cant diff erence in the incidence of DVT between these two procedures [5,10].