Predictors of Recanalization of the Great Saphenous Vein in Randomized Controlled Trials 1 Year After Endovenous Thermal Ablation

Objective/BackgroundThe objective was to identify predictors to develop and validate a prognostic model of recanalization of the great saphenous vein (GSV) in patients treated with endovenous thermal ablation (EVTA).MethodsThe search strategy of Siribumrungwong was updated between August 2011 and August 2014 using MEDLINE, Embase, and the Cochrane register to identify randomized controlled trials (RCTs), in which patients presenting with GSV reflux were treated with radiofrequency or endovenous laser ablation. Leg level data (n = 1226) of 15/23 selected RCTs were pooled. The primary outcome was recanalization of the GSV; the secondary outcome was change in health related quality of life (HRQoL) measured by the Chronic Venous Insufficiency quality of life Questionnaire or Aberdeen Varicose Vein Questionnaire 1 year post-procedure. Candidate predictors were age, sex, body mass index, clinical class, GSV diameter, saphenofemoral junction reflux, type of device, energy, and length of treated vein.ResultsAt 1 year, 130 GSVs were recanalized (11%). Clinical class (odds ratio [OR] 2.1, 95% confidence interval [CI] 1.4-3.3) and diameter (OR 1.8, 95% CI 1.2-2.7) of the GSV were the strongest predictors of recanalization. Other predictors included in the final model were sex, type of device, and length of treated vein. The performance of the recanalization model was moderate, with an area under the curve above 0.717. GSV diameter, type of device, and amount of energy delivered were the only predictors of the change of HRQoL. None of the candidate predictors were included in the final HRQoL model (R2 = .027).ConclusionThere are several important prognostic factors for GSV recanalization and change of HRQoL after EVTA. However, the performance of each model was unsatisfactory to allow use in clinical practice yet.