Technique of stent sizing in patients with symptomatic chronic iliofemoral venous obstruction—the case for intravascular ultrasound-determined inflow channel luminal area-based stenting and associated long-term outcomes

Abstract

ObjectiveFemoroiliocaval stenting has become the standard of care for patients with quality-of-life impairing chronic iliofemoral venous obstruction not responding to conservative measures. Although improvement after stenting has been noted in multiple large studies, sizing of stents has been subjective in nature with a general tendency to use smaller stents that would be required to relieve venous hypertension. This study evaluates the authors’ technique of using the intravascular ultrasound (IVUS) inflow channel luminal area to guide stent sizing. MethodsPatients who underwent femoroiliocaval stenting for quality-of-life impairing chronic iliofemoral venous obstruction and had failed conservative therapy from 2015 to 2021 were included in the study. Clinical outcomes including venous clinical severity score (VCSS), visual analog scale (VAS) pain score, and grade of swelling (GOS) were appraised before and after stenting. Also evaluated were quality of life (Chronic Venous Insufficiency Questionnaire-20 [CIVIQ-20] instrument) and stent outcomes including patencies and reinterventions. Comparisons were made between limbs that underwent placement of larger caliber stents (largest stent diameter >20 mm: >20 mm stent group) vs smaller caliber stents (largest stent diameter ≤20 mm: ≤20 mm stent group). t tests and analysis of variance were used to compare outcomes, whereas the Kaplan-Meier analysis was used to evaluate patencies with log rank used to compare the curves. ResultsA total of 300 patients (300 limbs) underwent stenting with a median age of 58 years. There was a preponderance of men (159 of 300), left laterality (176 of 300), and post-thrombotic syndrome (176 of 300). The median body mass index was 41. There were 120 limbs in the >20 mm stent group and 180 limbs in the ≤20 mm stent group. The median follow-up was 23 months. There was no significant difference in baseline VCSS, VAS pain score, or GOS between the two groups. However, there was a significant difference in IVUS-determined inflow channel luminal area between the two groups (228 mm2 >20 mm stent group vs 176 mm2 for ≤20 mm stent group [P < .0001]). After stenting there was a significant improvement in the VCSS, VAS pain score, and GOS at 6 weeks, 3, 6, 12, and 24 months (P < .0001) without any difference between the groups (P > .05). The CIVIQ-20 score also improved from 58 to 38 (P < .0001) for the entire cohort and for the two groups (P < .0001). Overall primary, primary-assisted, and secondary patencies at 60 months were 84%, 100%, and 100%, respectively. Reintervention rate was 10% without any difference between the groups. ConclusionsStent sizing using IVUS-determined inflow channel luminal area in patients undergoing stenting for quality-of-life impairing chronic iliofemoral venous obstruction resulted in a significant improvement in the VCSS, VAS pain score, GOS, and quality of life (CIVIQ-20) after stenting. Excellent stent patencies and low reintervention rates were also noted. IVUS-determined inflow channel luminal area represents an objective technique of stent sizing in comparison to the subjective techniques that currently exist.