In patients with chronic venous disease (CVD) and associated ipsilateral limb reflux, iliac vein stenting was shown to improve the prevalence of reflux and severity in the long term. This is the main concluding finding of a single-centre retrospective analysis of prospectively collected data published in the Journal of Vascular Surgery: Venous and Lymphatic Disorders (online).
According to authors Seshadri Raju and Michael Lucas (The Rane Center, Jackson, US) the effect of iliac vein stenting on ipsilateral limb reflux is unknown. Some authors have suggested that reflux may worsen when proximal stenosis is corrected. The authors analysed the long-term effect of iliac vein stenting on limb reflux in their own dataset, which they claim is “one of the largest in the literature”.
A total of 3,637 limbs in 3532 patients received iliac vein stent placement from 1997–2018. Prospectively collected data were extracted from the electronic medical record for retrospective analysis. A total of 2,250 limbs were excluded from the analysis because of additional superficial, deep, or perforator venous interventions (n=1,512), missing reflux data (n=635), or stent occlusions afterward (n=103). After these exclusions, a total of 1,387 limbs in 1,228 patients were deemed eligible for analysis. 747 (54%) limbs had no pre-stent reflux, but 632 (46%) limbs had pre-stent reflux. The median age was 57 (range 11–96) and 60 years (range 16–96) respectively. The male to female ratio in the limbs without pre-stent reflux and limbs with pre-stent reflux was 1:6 and 1:2 respectively, with a non-thrombotic and post-thrombotic ratio of 2:5 and 1:4, respectively.
The authors highlight that status of reflux, pre, and post-stent was available in seven individual valve segments per limb in the database, comprising a total of 9,653 valve segments. Additionally, functional tests of reflux—air plethysmography and ambulatory venous pressure—were available in 1,209 limbs.
Stented patients were examined for reflux during the follow-up period (1–26 years) at least once a year. In this analysis, segmental reflux prevalence, referred to as “reflux”, was detected by ultrasound. The severity of reflux was graded by three methods: reflux segmental score based on a total number of refluxive segments (range 0-7) in each limb, air plethysmography (venous filling index; [VFI90]), and ambulatory venous pressure measurement (venous refilling time [VFT]).
Pre-stent duplex reflux was present across superficial, deep, and perforator segments varying from 51% prevalence at the popliteal segment, and 7% at the deep femoral segment. The resolution of post-stent reflux ranged from 21% at the femoral vein segment, to 58% in perforators; reflux completely resolved in 23% of limbs with no residual reflux at any of the 7 valve segments studied per limb. The onset of new reflux following iliac vein stent placement was rare, with a median of only 7% of segments at risk. Cumulative improvement in reflux and severity is shown in Figure 1.
The functional tests of reflux demonstrated improvement of 60% and 52% for VFI90 and VFT respectively. VFI 90 and VFT normalized in 31% and 24% of limbs respectively, with pre-stent reflux. The authors conclude that reflux prevalence and severity improve following iliac vein stenting in the long term. They hypothesise that the improvement/resolution of reflux is related to decompression of the valve station following stent placement. Collateral reflux completely resolved in some patients following stent placement.