Venous stenting was a hot topic on the agenda of the recent American Venous Forum (AVF) annual meeting (23–26 February, Orlando, USA). Catching the audience’s attention, one presenter highlighted a head-to-head study of dedicated versus non-dedicated stents.
“Iliofemoral venous obstruction when not adequately treated results in chronic debilitating disease and poor quality of life,” said Lillian Tran (University of Pittsburgh Medical Center, Pittsburgh, USA), who noted that deep venous stenting is “increasingly preferred” as the mainstay treatment over medical therapy alone.
According to Tran, this move towards stenting necessitates studies comparing the performance of novel, dedicated venous stents with the more traditional, non-dedicated stents. At AVF, Tran reported the findings of such a head-to-head study at a single centre, detailing that the use of dedicated venous stents was associated with a significant reduction in extension into the inferior vena cava (IVC) without reduced early patency rates compared to non-dedicated stents.
The presenter stressed that outcomes after iliac vein stenting rely on multiple technical considerations and stent attributes. “In addition to adequate sizing and consistency in deployment, […] venous stents must establish a balance between radial force, flexibility and crush resistance,” she informed the audience. Tran detailed that dedicated, nitinol-based stents have been developed to meet these requirements and are now on the market in the USA and Europe. Four of these stents have been approved by the US Food and Drug Administration (FDA) for venous indications, the presenter relayed, noting, however, the fact that the Vici (Boston Scientific) and Venovo (BD) stents were recalled last year.
Outcomes data from investigational device exemption (IDE) trials of the four dedicated venous stents have demonstrated excellent patency rates, Tran communicated. However, she highlighted that head-to-head, comparative performance data against the more traditional Wallstent (Boston Scientific) and other non-dedicated stents are limited.
Tran et al therefore performed a retrospective review of all patients who underwent iliofemoral venous stenting for acute thrombotic, post-thrombotic and non-thrombotic indications at their institution between 2014 and 2021, grouping patients based on the use of novel, dedicated venous stents versus non-dedicated stents during their treatment.
The team measured 30-day stent failure and one-year patency rates as primary outcomes, Tran detailed, adding that secondary outcomes included stent sizing and extension.
A total of 135 patients (186 limbs) were treated in the study, Tran told AVF attendees, specifying that 63 limbs were treated using novel dedicated stents, while 123 were treated using the traditional Wallstent or another non-dedicated stent.
The team noted no preference in stent type in treating acute thrombotic or post-thrombotic lesions at their institution, but they did observe that dedicated venous stents were more likely to be used in non-thrombotic lesions.
Addressing the AVF audience, Tran reported that fewer stents were deployed per limb with the use of novel dedicated venous stents. In addition, she revealed that one patient had a stent fracture without thrombosis, and that there were no cases of deployment failure or stent migration in either group.
Additionally, larger size was observed in limbs using the Wallstent alone compared to dedicated venous stents and proximal stent extension into the IVC greater than 50% was significantly reduced with the use of novel venous stents compared to the non-dedicated devices, Tran detailed.
The presenter relayed some further key outcomes from the study: “Overall, dedicated venous stent use was not significantly associated with differences in early stent patency rates, nor was it a predictor of 30-day stent failure using a logistic regression analysis.”
In addition, she reported that primary patency rates remain comparable between novel venous stents and non-dedicated stents at one year. On subgroup analysis, the researchers did not see any differences between the non-dedicated and dedicated stents in either 30-day or one-year stent patency rates.
Tran acknowledged some limitations of the group’s study, including its retrospective nature, small sample size, short follow-up and no concurrent measurement of clinical improvement.
“In our experience, we found a significant reduction in extension into the IVC, total number of stents deployed and mean stent diameter with the use of novel, dedicated venous stents compared to Wallstents alone,” Tran concluded. In addition, she recapped that there were no significant differences in early outcomes between the two stent types.