Predictive factors of venous stenting failure: a systematic review

Abstract

OBJECTIVE: Venous stenting of iliocaval obstructions has become a more frequent procedure over the last two decades. In-stent stenosis and thrombosis are potential complications, causing one of the main causes of symptoms recurrence and impacting quality of life. The aim of this review is to report on the impact of venous stent patency loss, as well on risk factors and management. METHODS: A systematic review was conducted according to the recommendations of the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) statement. RESULTS: After a literature search, 12 studies (two prospective and 10 retrospective studies) were included in the analysis. A total of 1981 patients (34.1% male) and 2388 limbs (63.6% left side) were assessed. Mean age was 43.5 years (range 16-99). Indication for stenting included deep venous thrombosis (DVT) (4%), post-thrombotic syndrome (PTS) (18.8%) and non-thrombotic iliac vein lesions (NIVLs) (77.2%). Regarding treatment, most patients were submitted to angioplasty and stenting only (87%). Associated catheter directed thrombolysis or mechanical thrombectomy was performed when indicated (8.4%), and in the remaining an AVF/endophlebetomy was performed (4.6%). Primary, primary assisted and secondary patency rates at one year ranged from 68-100%, 79-90% and 85.8-100%, respectively. Reported anticoagulation duration after stenting ranged from 1-12 months. In one study involving only patients treated for NIVLs, no anticoagulation was prescribed, and antithrombotic therapy was continued for three months. Follow-up strategies included clinical and imagiological control with a mean follow-up of 19.7 months. Post-procedural stent re-stenosis was reported in 121 limbs (5.1%) and stent occlusion in 81 limbs (3.4%); the latter was distributed as follows: 11.1% after DVT, 77.8% PTS and 11.1% NIVLs. A total of 186 re-interventions were performed in symptomatic patients. The prognostic factor most consistently associated with stent failure was thrombotic inflow veins. Other reported factors were incomplete thrombolysis and age younger than 40 years. Stent placement below the inguinal ligament, type of stent and anticoagulation regimen do not seem to affect stent patency. CONCLUSION: Regarding venous lesions of the lower limbs, a selective approach and planning should focus on identification of risk factors for stent failure. It is noteworthy that most stent occlusions occur in post-thrombotic limbs. Stent failure continued after 6 months, emphasizing the importance of an extended surveillance especially on these patients.

Keywords

• Venous stent thrombosis
• postthrombotic syndrome
• may-thurner syndrome