Background: The study aims to identify the incidence of symptomatic and asymptomatic venous thromboembolism (VTE) after minimally invasive varicose vein surgery and to assess the predictability of the Caprini risk score (CRS).
Methods: CAPrini Score In Venous Surgery (NCT03041805) is a registry-based prospective study that enrolls patients undergoing minimally invasive open (high ligation, stripping, miniphlebectomy) and endovascular (thermal and non-thermal ablation) surgery on varicose veins. The main inclusion criteria are CRS assessment before intervention and a duplex ultrasound scan performance within 2-4 weeks after surgery. The primary outcome is a combination of asymptomatic or symptomatic DVT, including EHIT of class 2-4 and PE.
Results: Totally 1878 records with defined outcomes were analyzed. The mean age of patients was 46.9±13.3 years; 66% were female. Endovenous laser ablation was performed in 88%. Varicose tributaries were treated in 40%, perforating veins in 3.9% of cases. CRS ranged from 1 to 12 (mean of 4.0±1.5). Prophylactic anticoagulation was prescribed in 20%. The primary outcome was reported in 63 cases (3.4%; 95% CI, 2.7-4.3%), comprising asymptomatic (N.=29, 1.5%) or symptomatic (N.=10, 0.5%) DVT or EHIT (n=28, 1.6%). No PE was reported. A significant correlation was found between CRS and VTE incidence (P=0.001). Under logistic regression CRS (OR, 1.3; 95% CI, 1.1-1.6) along with treatment of tributaries (OR, 6.3; 95% CI, 3.0-13.0) and perforating veins (OR, 10.7; 95% CI, 3.8-30.2) were associated with VTE in the absence of prophylactic anticoagulation.
Conclusions: The incidence of VTE after ablation of superficial veins is 3.4%, predominantly due to asymptomatic EHIT and DVT, and significantly correlates with CRS.