Peripheral venous hypertension in chronic venous disease.

Background: Microvascular venous hypertension has emerged as a central feature of chronic venous disease (CVD). Yet, the incidence and severity of peripheral venous hypertension in the clinical setting have not been reported. This is an observational study of venous hypertension in the lower limb of a large cohort of patients with suspected CVD referred to a single referral center during a 16-year period.

A comparison between intravascular ultrasound and venography in identifying key parameters essential for iliac vein stenting.

Objective: Deep venous stenting has become the primary treatment option for obstructive venous disease. Precise identification and quantification of the disease as well as localization of optimal landing zones are key elements to success. Compared with venography (anteroposterior projection), intravascular ultrasound (IVUS) seems to be more sensitive in determining those parameters.

Ambulatory venous pressure, air plethysmography, and the role of calf venous pump in chronic venous disease.

Background: Ambulatory venous pressure (AMVP) records pressure dynamics with calf exercise. Air plethysmography (APG) measures related volume detail. APG has been suggested as a noninvasive surrogate for AMVP.

Caliber-targeted reinterventional overdilation of iliac vein Wallstents.

Background: Wallstents (Boston Scientific, Marlborough, Mass) are most commonly used in iliac-caval stenting. Approximately 20% of stented limbs require reintervention to correct in-stent restenosis (ISR) or stent compression (SC). Corrective balloon dilation to rated stent caliber (isodilation) is not always successful.

Impact of degree of stenosis in May-Thurner syndrome on iliac vein stenting.

Objective: May-Thurner syndrome (MTS) patients with lifestyle-limiting symptoms undergo stenting of the iliac vein for relief of compressive disease. The impact of degree of stenosis on clinical symptoms and outcomes after stenting is unknown and examined in our study.

Methods: Retrospective review of contemporaneously entered data of 202 patients who underwent stenting for MTS between 2005 and 2011 was performed.

Characteristics and outcomes of stent occlusion after iliocaval stenting.

Objective: With increasing use of iliocaval stenting, complications have become more noticeable. Stent occlusion is one such outcome that has not been studied in detail. Characteristics of stent occlusion in addition to outcomes after recanalization are presented.

A systematic review of the efficacy and limitations of venous intervention in stasis ulceration.

Background: Surgical techniques to address various components of chronic venous disease are rapidly evolving. Their efficacy and generally good results in treating superficial venous reflux (SVR) have been documented and compared in patients presenting with pain and swelling. A growing amount of literature is now available suggesting their efficacy in patients with venous leg ulcer (VLU).

Factors influencing peripheral venous pressure in an experimental model.

Background: Peripheral venous hypertension and microvascular injury have merged as central features of chronic venous disease. Peripheral venous pressure in the lower limb is controlled by central and peripheral mechanisms. In the current manuscript, we examine the role of peripheral factors, particularly conduit capacitance compliance, focal stenosis, and arterial inflow into the calf.

Optimal sizing of iliac vein stents.

Background Iliac vein stenting has emerged as a therapeutic option in chronic venous disease. The optimal stent size is unknown but should match normal caliber at a minimum. Methods Teleology: The iliac-femoral outflow caliber was measured by Duplex in healthy volunteers to determine normal caliber.

Outcomes of iliac vein stents after pregnancy.

Objective: Stenting is the first-line treatment for obstructive iliocaval lesions when intervention is required. The aim of the study was to evaluate iliocaval stent patency during and after pregnancy in women of reproductive age who became pregnant after stent placement.

Methods: Female patients of reproductive age (18-45 years old) who underwent iliocaval stenting between May 2007 and March 2014 were identified from a three-center prospectively maintained database.

Deep venous thrombosis associated with caval extension of iliac stents.

Background: It is generally difficult to place an iliac vein stent precisely at the iliocaval junction with venographic control or even with intravascular ultrasound guidance. Furthermore, mechanical properties of the Wallstent (Boston Scientific, Marlborough, Mass) can predispose precisely placed stents to distal displacement or stent collapse. Our center has thus advocated extending Wallstents 3 to 5 cm into the inferior vena cava to prevent complications of missed proximal lesions or stent migration.

Endovascular management of chronic total occlusions of the inferior vena cava and iliac veins.

Objective: Percutaneous recanalization and stenting is currently the standard of care for symptomatic chronic total occlusions (CTOs) of the iliofemoral veins. CTO lesions involving the inferior vena cava (IVC) present a more complex patient subset. In this series we describe our single-center experience with endovascular recanalization of symptomatic occlusions of the IVC.

Compression use in the era of endovenous interventions and wound care centers.

Background: Compression has long been the mainstay of treatment in chronic venous disease (CVD). The current treatment paradigm emphasizes compression as primary treatment, awarding saphenous ablation only an optional role. The advent of endovenous interventions, such as endovenous ablation (EVA) of the saphenous vein and iliac vein stenting, has dramatically expanded therapeutic options.

Relative importance of iliac vein obstruction in patients with post-thrombotic femoral vein occlusion.

Background: Patients with femoral vein occlusion rapidly develop collateral flow through the deep femoral vein, an embryonic collateral. In contrast, iliac vein collateralization is sparser and functionally poorer. It is not uncommon to have femoral vein occlusions associated with iliac vein obstruction, even though the femoral vein occlusion is often more readily apparent on venograms and duplex scans, whereas the iliac vein obstruction may remain occult.

Effect of External Positive and Negative Pressure on Venous Flow in an Experimental Model.

Objective: Positive external pressure is said to decrease transmural pressure; negative pressure in the pleural cavity is widely believed to result in negative pressure in systemic chest veins. The discrepancy between erect column height and foot venous pressure has been explained on this basis.

Methods: These core concepts rest on static closed models that may not be appropriate.

Treatment of iliac-caval outflow obstruction.

The importance of the obstructive component in chronic venous disease (CVD) with ulceration has been emphasized recently for a venous condition that has primarily focused on the reflux component. Modern imaging techniques, particularly intravascular ultrasound, have shown the frequency of the obstructive element in both post-thrombotic and nonthrombotic disease. The emergence of iliac vein stent angioplasty and its good results in the treatment of large vein and other diverse CVD subsets has strengthened the role of obstruction.

Utility of iliac vein stenting in elderly population older than 80 years.

Background: The geriatric population aged 80 years and older with severe manifestations of chronic venous disease face diminishing therapeutic options. Self-applied compression is often not possible because of frailty or arthritis. Significant limb swelling diminishes mobility, affects independent living, and precipitates institutionalization.

Quantifying saphenous reflux.

Background: Quantification of reflux is desirable in advanced chronic venous disease as clinical features are based on its adverse impact on ambulatory venous pressure (AMVP). Prior clinical observation suggests that reflux in a saphenous vein > 5 mm is likely significant. On the basis of normal calf pump mechanics, we hypothesized that a reflux volume ≥ 30 mL was necessary to upset pump equilibrium.

Anomalous features of iliac vein stenosis that affect diagnosis and treatment.

Background: Endovenous management of venous lesions is largely derived from arterial experience. However, venous lesions, particularly iliac vein stenoses, differ from their arterial counterparts in some crucial respects. Awareness of these differences is necessary for proper diagnosis and treatment.

Assessment of residual thrombus after venous thrombolytic regimens.

Background: We noticed substantial residual thrombus on intravascular ultrasound (IVUS) in many limbs despite restoration of flow after thrombolysis. Since thrombus burden has been tied to post-thrombotic syndrome (PTS), the frequency and extent of residual thrombus after thrombolysis is important. We present such an analysis below.

A modification of iliac vein stent technique.

Background: Iliac vein stenting has emerged as a promising new technology to address a wide spectrum of advanced chronic venous disease. Wallstent™ has been the commonest stent type used in reported experience. It has excellent long-term patency with good clinical outcome, but is prone to compression/migration of the upper end of the stent requiring reinterventions.