Midterm Results of IlioFemoral Venous Stenting: Venous Stent Length Is Still Not a Risk Factor for Stent Thrombosis

Venous stenting has become the treatment of choice for symptomatic outflow obstructions secondary to acute Deep Venous Thrombosis (aDVT) with venous compression, nonthrombotic iliac vein lesions (NIVLs) and post-thrombotic stenoses (PTS). There is little data evaluating the association between stent length and patency in patients treated for iliofemoral venous outflow obstructions. We previously evaluated the association between stent length and patency and found that at 6 months total stented length was not a risk factor for stent thrombosis. We have now evaluated stent patency at 24 months.



Methods:

From January 2016 to April 2021, a total of 161 patients underwent venous stenting for NIVLs and thrombotic disease including aDVT and PTS. Patient characteristics included age, gender, body mass index, diagnosed thrombophilia, prior history of venous thromboembolism, and CEAP score.  Venography and intravascular ultrasound (IVUS) were used. IVUS findings were used to determine stent length and diameter. Patients were divided into two groups: total stented length >100 mm and < /=100 mm with midterm results defined as duplex at 24 months. The primary end point was stent patency. The secondary endpoint was stent migration. Additional variables assessed were Venous Clinical Severity Scores (VCSS) and Villata scores.



Results:

A total of 76 patients (63.2% female) had 24-month imaging. Median age was 60 years. Mean BMI was 33.2±7.0 kg/m². Patency at 24 months was 85.5%.  Forty-two (55.3%) had a total stent length >100 mm with a 24-month patency of 78.6%. Thirty-four (44.7%) patients had a total stent length < /=100 mm with a 24-month patency of 94.1%. The primary endpoint revealed patency between the 2 groups was not statistically significant (p-value=0.053). Stent patency at 24 months was 90.3% (28 of 31) for patients with NIVLs. Stent patency for patients with PTS was 83.3% (10/12). Stent patency was 81.8% (27 of 33) for patients with aDVT who underwent stenting after thrombectomy (Table 1). Additionally, when considering the secondary endpoint there were no stent migrations in any of the patient cohorts.



Conclusions:

Our institution previously reported that stent length was not a risk factor for thrombosis at 6 months. Longer follow up is needed given the expected longer patient life expectancy in these patient cohorts. This midterm analysis confirms no correlation between stent length and stent patency at 24 months follow-up. The stent length should be adequate to treat the diseased venous segment without additional concern that a longer stent will increase the risk of stent thrombosis.