Assessment of flow mechanics in the lower extremity venous system.

Background: The Reynolds number (R) is a dimensionless parameter that describes fluid flow mechanics. Veins are compliant and collapsible vascular conduits that can accommodate large volume changes in response to small pressure changes. However, only sparse information is available about flow parameters such as the R in the venous system.

Clinical tolerance of untreated reflux after iliac vein stent placement.

Background: We have recently demonstrated in a large patient cohort that the prevalence and severity of reflux will improve in most limbs after stenting and that most limbs will not develop new-onset reflux. In the present report, we have focused on the long-term clinical outcomes associated with untreated reflux in the same patient cohort who had undergone iliofemoral venous stenting without correction of residual reflux.

Methods: The clinical outcomes data from 1379 limbs treated with only iliac vein stenting without correction of superficial or deep reflux from 1997 to 2018 were analyzed (23-year follow-up period).

Role of lower extremity fasciectomy plus fasciotomy for patients with persistent leg pain after stenting for chronic iliofemoral venous obstruction.

Although clinical improvement after stenting for symptomatic iliofemoral venous obstruction has been demonstrated in multiple large studies, a small proportion of patients will experience persistent quality of life-impairing symptoms. Swelling in such a setting represents the concomitant presence of lymphedema and will respond to treatment directed at the lymphedema. In contrast, persistent pain likely arises from venous hypertension in the lower leg, leading to the development of chronic compartment syndrome.

Utility of a percutaneous mechanical thrombectomy device in retrieval of an iatrogenic intravascular foreign body.

Intravascular foreign bodies can result from endovascular procedures and from other medical implants and devices. A wide variety of techniques and devices have been described for the retrieval of such intravascular foreign bodies in reported studies. In the present report, we have described the case of a patient with a symptomatic left innominate vein deep vein thrombosis who also had a retained catheter fragment from a fractured tunneled infusion catheter in the left innominate vein.

Improvement following restoration of inline flow argues against comprehensive thrombus removal strategies and for selective stenting in acute symptomatic iliofemoral venous thrombosis.

Objective: Randomized trials have demonstrated the benefit of thrombus removal strategies in iliofemoral deep venous thrombosis (IFDVT) in providing early symptom relief and decreasing the incidence of post-thrombotic syndrome (PTS), especially severe PTS. However, the impact of quantum of residual thrombus burden (RTB) on PTS as determined by intravascular ultrasound examination and the role of venous stenting in the acute setting have not been evaluated and represent the focus of this study.

Methods: Sixty-nine limbs (65 patients) undergoing thrombus removal for acute symptomatic IFDVT between 2015 and 2021 formed the study cohort.

Percutaneous laser recanalization in chronically occluded iliofemoral venous stents.

Occlusion is a challenging complication of endovenous stenting. The treatment of chronic iliofemoral stent occlusion involves wire recanalization followed by balloon angioplasty. However, this approach will not always be successful.

Comparison between a dedicated venous stent and standard composite Wallstent-Z stent approach to iliofemoral venous stenting: Intermediate-term outcomes.

Objective: Dedicated venous stents have not been used in the management of symptomatic chronic iliofemoral venous obstruction (CIVO) until recently. The Bard Venovo stent (Becton, Dickinson, and Co, Franklin Lakes, NJ) is one such stent noted to have an increased chronic outward force and radial resistive force compared with the Wallstent (Boston Scientific, Marlborough, MA). In the present study, we evaluated the outcomes following the use of the Bard Venovo stent vs a matched cohort of limbs that had undergone stenting with the Wallstent-Zenith (Z) stent (Cook Medical Inc, Bloomington, IN) composite configuration.

Iliofemoral venous configurations from three-dimensional computed tomography venogram and their relevance to stent design.

Objective: Iliofemoral venous stenting has become the standard of care for patients presenting with quality-of-life impairing symptoms of chronic iliofemoral venous obstruction not responding to conservative measures. This has led to an increased use of venous stenting over the last several years. However, iliofemoral venous anatomy in patients requiring such intervention remains poorly elucidated.

Options in the treatment of superficial and deep venous disease in patients with Klippel-Trenaunay syndrome.

Objective: Klippel-Trenaunay syndrome (KTS) is a congenital mixed mesenchymal malformation syndrome that includes varicose veins, capillary and venous malformations, lymphatic abnormalities, and hypertrophy of various connective tissue elements. The purpose of the present study was to describe the clinical characteristics and outcomes in a subset of patients with KTS in whom venous interventions, including iliofemoral venous stenting, were performed after failure of conservative therapy.

Methods: A single-center retrospective data review of 34 patients with KTS who had undergone interventions for venous disease between January 2000 and December 2020 was performed.

Extension of iliac vein stent into the profunda femoral vein for salvage.

Background: The extension of iliac vein stents into the common femoral vein is often required to correct stenoses found at or near the inguinal ligament. Very rarely, an extension of the iliac stent into the profunda femoris vein may be required because of severe disease at the femoral trijunction. Profunda extension of iliac vein stents is a rare but useful technique for salvage.

Comparison of intravascular ultrasound and magnetic resonance venography in the diagnosis of chronic iliac venous disease.

Background: The diagnosis of chronic iliofemoral venous obstruction (CIVO) can be made with several different modalities. Intravascular ultrasound (IVUS) examination is the gold standard in the diagnosis of CIVO. However, being invasive, it should not be the initial examination to screen patients with CIVO.

Long-term improvement of limb reflux prevalence and severity after iliac vein stent placement.

Background: The effect of iliac vein stenting on ipsilateral limb reflux is unknown and has remained a matter of speculation. It has been suggested that the propensity for reflux might worsen when proximal stenosis is corrected. This could allow for retrograde flow with coughing and the Valsalva maneuver, stressing the valve.

An overview of in-stent restenosis in iliofemoral venous stents.

Background: Although endovenous stents have been associated with overall low morbidity, they can require reinterventions to correct stent malfunction due to in-stent restenosis (ISR). ISR has often occurred iliofemoral venous stents but has not been well described. It has been reported to develop in >70% of patients who have undergone iliofemoral venous stenting.

Iliofemoral venous stenting in patients with central neuromuscular disorders.

Background: Leg swelling in patients with various central neuromuscular disorders is a common clinical scenario and can lead to significant morbidity. The aim of the present study was to evaluate a subset of patients with central neuromuscular disorders who had undergone iliofemoral venous stenting at a specialty venous clinic at a tertiary care hospital.

Methods: From January 2000 to December 2020, the medical records of all patients with a known central neuromuscular disorder who had undergone iliofemoral venous stenting for chronic iliofemoral venous obstruction were retrospectively analyzed.

Management of iatrogenic inferior vena cava perforation with composite Wallstent-Z-stent technique.

Inferior vena cava rupture is uncommon but can occur as a result of trauma or catheterization and during venous interventions. We have described two cases of iatrogenic inferior vena cava perforation, with their successful management with bare metal stents (a composite Wallstent-Z-stent technique). This management strategy was possible owing to the unique properties of the venous system.

Utility of a Mechanical Thrombectomy Device in Treating Calcified Instent Restenosis Post Iliofemoral Venous Stenting.

Instent restenosis (ISR) following iliofemoral venous stenting is quite common with up to three-quarters of patients developing some degree of ISR. However, only around 16% develop recurrent symptoms impairing their quality-of-life meriting reintervention. The first line of treatment for such ISR involves the use of angioplasty balloons to recreate an adequate flow channel.