Modification of endothermal heat-induced thrombosis follow-up strategy using a risk stratification model after endovenous thermal ablation.

Abstract

ObjectiveTo develop and validate a risk stratification model that identifies varicose vein patients at high risk of Endothermal Heat-Induced Thrombosis (EHIT) following thermal ablation to guide optimized surveillance and anticoagulation strategies.MethodsIn this single-center retrospective cohort study, a total of 525 affected limbs treated by radiofrequency and microwave ablation were included. Patients were randomly assigned to a training cohort (n = 368) and a validation cohort (n = 157) in a 7:3 ratio. Preoperative clinical data, including Great saphenous vein (GSV) diameter, reflux time, sex, and Clinical Etiology Anatomy Pathophysiology (CEAP) classification, were analyzed. Predictors were identified through Spearman correlation and χ² tests. The model's performance was assessed using C-index and confusion matrix in the validation cohort. All data analysis and visualization were performed using R software, with a p-value below 0.05 considered statistically significant.ResultsEHIT occurred in 24 patients (overall rate: 4.57%) at 1 week postoperatively. Of these, 21 were EHIT class I and 3 were EHIT class II. Significant predictors included GSV diameter, reflux time, CEAP classification and sex. The logistic regression model demonstrated strong calibration and discrimination (C-index = 0.853 in train cohort), with an optimal risk threshold of 5.4% established for risk stratification. In the validation cohort, the model achieved 79.61% accuracy, 100% sensitivity, and 78.8% specificity. A web-based calculator was developed to assist clinicians in estimating individual EHIT risk and guiding surveillance strategies.ConclusionWe identified sex, GSV diameter, reflux time, and CEAP classification as predictors and developed a logistic model with a 5.4% risk threshold for EHIT stratification. For patients classified as average-risk, omission of routine ultrasound surveillance could be considered, whereas high-risk patients may benefit from intensified ultrasound surveillance and extended anticoagulation, but external multicenter validation is required before adoption in clinical practice.