Safety of Iliac Vein Stenting in the Office-Based Laboratory: Experience with 4,312 Nonthrombotic Iliac Vein Lesions

OBJECTIVE: The study aims to evaluate the incidence of thirty-day thrombosis following iliac vein stent placement, stratified by age, and to analyze long-term follow-up outcomes. METHODS: A retrospective analysis was conducted of 4,312 procedures performed in 2,642 patients with symptomatic chronic venous insufficiency (CEAP clinical classes 3-6) from 2012 to 2024. Patients underwent iliac vein assessment using intravascular ultrasound (IVUS) and received stent placement. Follow-up included iliac vein duplex ultrasound assessments at 3 to 7 days postoperatively, with additional evaluations at 3 to 6 months during the first year. For subsequent years, follow-up occurred at 6 to 12-month intervals. Intraoperative heparin was not administered, and postoperative management included daily clopidogrel (Plavix). Stents were assessed for partial and complete thrombosis. RESULTS: The mean age of the study population was 73 years (range, 30-108), with 39.30% male and 60.70% female patients. Age distribution by decade, based on the number of nonthrombotic iliac vein lesions (NIVLs) treated, was as follows: patients in their 30s (43), 40s (151), 50s (498), 60s (926), 70s (1,116), 80s (1,035), and >90 years (543). Thirty-day thrombosis rates by age group were: 30s (0%), 40s (0.01324%), 50s (0.0200%), 60s (0.0118%), 70s (0.0179%), 80s (0.0116%), and >90s (0.0074%). Thirty-day thrombosis rates by CEAP clinical class were: CEAP 3 (0.01395%), CEAP 4 (0.0121%), CEAP 5 (0.0172%), and CEAP 6 (0.0166%). Among patients with thrombosis within 30 days of stent placement, 76.3% experienced partial stent thrombosis and 27.7% experienced complete stent thrombosis. The mean age of patients with complete thrombosis was 71.4 ± 17 years, compared with 71.8 ± 12 years for those with partial thrombosis. Of patients with complete thrombosis, 71.43% were female. Of the 14 patients with complete thrombosis within 30 days, 10 cases occurred between 2012 and 2021, three in 2022, and one in 2023. Binary logistic regression revealed no significant association between thirty-day thrombosis and age (p = 0.719), CEAP clinical class (p = 0.938), or laterality (p = 0.326). CONCLUSIONS: Iliac vein stenting for symptomatic nonthrombotic iliac vein lesions (NIVL) is a safe and effective procedure with a low incidence of early thrombosis. Age, laterality, and CEAP clinical class were not significantly associated with 30-day thrombosis outcomes. This study supports the use of iliac vein stenting in patients across a broad spectrum of CVI severity, demonstrating its effectiveness in an outpatient-based laboratory (OBL) setting.