Publications by authors named "Riley Kuykendall"

Article Synopsis
  • The study explores the design of stents and conduits with a gradually expanding caliber to reduce flow resistance and prevent flow separation, compared to conventional cylindrical stents.* -
  • Experiments involved testing conduits of various initial calibers (2-5 mm) and lengths (160-620 mm) at different pressures (10 and 25 mm Hg) to evaluate their flow rates in comparison to traditional designs.* -
  • Results showed that the expanding caliber conduits significantly improved flow rates by 1-55%, with computational fluid dynamics simulations confirming optimal expansion rates that minimize flow separation and resistance.*
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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.

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Article Synopsis
  • * While generally effective, this technique can lead to a long-term complication where one stent compresses the other due to a compliance mismatch, often going unnoticed without an ultrasound examination.
  • * A possible solution to alleviate this complication could involve creating a cross-fenestration between the stent barrels, reinforced by a Z stent, especially if the barrels have a short extension into the vena cava.
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Minimum iliac vein caliber necessary to maintain normal peripheral venous pressure can be derived by the Poiseuille equation. Duplex was compared to intravascular ultrasound (IVUS) in the assessment of iliac vein stenosis in this single center retrospective study. Parallel IVUS and duplex caliber data for common iliac vein (CIV) and external iliac vein (EIV) in 382 limbs were separately compared.

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Background: Veins are thin-walled tubes. Their lumen is roughly circular with an aspect ratio close to 1:1 under physiologic pressures. When they collapse owing to decreased internal pressure or external compression, the aspect ratio changes.

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Background: Phasic venous flow variation with respiration is surrounded by controversy and not well understood. The current concept assigns a major role to the "abdominal pump." According to this model, inspiratory increases in abdominal pressure compress the vena cava, increasing its internal venous pressure and propelling blood upstream.

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Objective: An endovascular approach has essentially replaced open surgery in the management of symptomatic chronic obstructive iliofemoral venous disease. In the last several years, such a minimally invasive approach has shifted from use of Wallstents alone to a combination of Wallstent-Z stent (composite stenting) to better deal with the iliocaval confluence. This study evaluates the clinical and stent related outcomes following use of composite stenting.

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Background: Iliac vein stenosis is a frequent pathologic process in advanced chronic venous disease. Intravascular ultrasound (IVUS) has emerged as the "gold standard" to diagnose iliac vein stenosis and to guide stent treatment. A pre-IVUS test is often obtained.

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