Racial Disparities in PAD-Related Amputation Rates among Native Americans and non-Hispanic Whites: An HCUP Analysis.

INTRODUCTION: This study analyzed the impact of sociodemographic characteristics, patient comorbidities, risk factors for critical limb ischemia and hospital characteristics on racial disparities in amputation rates for Native American patients with peripheral artery disease (PAD). METHODS: The study used the Healthcare Cost and Utilization Program inpatient discharge data from 2006-2013 for patients with a primary diagnosis of PAD. Multivariable models using the Blinder-Oaxaca decomposition method were estimated to isolate the impact of individual covariates to identify determinants of amputation rates for Native Americans compared with non-Hispanic Whites. RESULTS: Region of the country made a difference in this analysis with Native Americans residing in the West Census Region being twice as likely to undergo amputation as non-Hispanic Whites. CONCLUSIONS: After adjusting for sociodemographic characteristics, patient comorbidities, and hospital characteristics, Native Americans with PAD who reside in the West Census Region are substantially more likely to undergo amputation than are non-Hispanic Whites.

Pilot Study to Determine Safety and Efficacy of Paclitaxel Infusion in De Novo Peripheral Lesions Using the Atrium ClearWay Balloon.

OBJECTIVE: To evaluate the safety and efficacy of a one-time infusion of paclitaxel through an Atrium ClearWay balloon in infra inguinal de novo peripheral lesions. METHODS: This is a single-center prospective study looking at treatment of 50 limbs. Treatment includes standard infra inguinal endovascular revascularization followed by a pre-prescribed infusion of paclitaxel. Control is standard reintervention without subsequent paclitaxel infusion. Patients were followed at one, four, and 10 months with ankle-brachial index (ABI)s, arterial duplex of the treated limb, and Rutherford classification stage measured before and after procedures and at each follow-up. Freedom from binary restenosis was tracked with duplex ultrasound, and freedom from target lesion revascularization (TLR) was also tracked in the treatment group. Binary restenosis and TLR data was harvested from the patient record for the control group. RESULTS: Average ABI and Rutherford classification stage improved as expected. The treatment group had a freedom from TLR rate of 86 percent and a freedom from binary restenosis rate of 80 percent at 10 months. Average ABI improved from 0.65 at baseline to 0.94 at 10 months in the treatment group. The control group had a 72 percent freedom from TLR and a 58 percent freedom from binary restenosis at 10 months. Average ABI of the control group improved from 0.67 at baseline to 0.85 at 10 months in the control group. There were no amputations, open bypass revascularizations, or hypersensitivity reactions observed in the treatment group. CONCLUSIONS: Infusion of paclitaxel in de novo lesions appears to be a safe and efficacious treatment in the peripheral vasculature when compared to a historical control group. While it is early, it appears that the patients do receive some benefit from this one time infusion, and this approach should be studied further.

Pulmonary Embolism Caused by Popliteal Vein Aneurysm: A Case Report.

In this case report, we describe an unusual episode of bilateral submassive pulmonary embolism (PE) caused by a popliteal vein aneurysm (PVA). The development of PE stems from many risk factors including obesity (BMI³ 30 kg/m2), hypertension, cigarette smoking (greater than 25 cigarettes per day), increasing age, surgery, immobility, malignancy, and inherited thrombophilia. A PVA is a rare but significant cause of PE. A 28-year-old male presented to the emergency department with progressive shortness of breath. He had no significant past medical history, no family history of deep vein thrombosis or PE, and no recent surgeries, travel, or trauma. A physical exam revealed he was saturating 96 percent on 2 L/minute oxygen through a nasal cannula and was noted to have a heart rate in the 90 beats per minute range that quickly increased to 150 beats per minute with minimal exertion. An initial laboratory workup was unrevealing except for an elevated D-dimer. A chest radiograph demonstrated no cardiopulmonary abnormalities. Computed tomography angiography of the chest was performed and revealed multiple bilateral pulmonary emboli. An urgent echocardiogram then revealed evidence of right heart strain with a dilated right ventricle. A subsequent bilateral venous duplex scan of the lower extremities was performed, which revealed a left PVA. Vascular surgery was performed, specifically emergent catheter-directed lysis with the placement of a temporary inferior vena cava (IVC) filter. The patient was started on rivaroxaban oral anticoagulation therapy and then discharged home without incident. Several months later, he underwent uncomplicated surgical repair of his left PVA. This case illustrates PVA as a rare but noteworthy cause of PE. Doctors should consider this diagnosis in patients with recurrent PE or when the cause of PE is unknown. Although the exact etiology is not known, inflammation, trauma, degenerative changes, and congenital weakness of venous wall have all been proposed as causes of venous aneurysms. The definitive management of a PVA is surgical repair. Some studies suggest recurrent PE in as high as 80 percent of patients on oral anticoagulation alone. Therefore, an IVC filter is often placed to prevent further thrombi progression until definitive surgical treatment of the aneurysm has been performed.

Rural United States Experience of Incorporation of a Technologically Advanced and Procedurally Complex Cardiovascular Program - the Sanford Trans-Catheter Aortic Valve Replacement Experience.

Trans-catheter aortic valve replacement (TAVR) was approved by the U.S. Food and Drug Administration in 2012 for treatment of severe symptomatic aortic stenosis in non-surgical and high risk patients. Implementation of this complex procedure requires a comprehensive heart team approach. Rural demographics in the Midwest pose many challenges related to low volumes of operations both at institutional and individual levels, leading to serious concerns about the quality of care delivered in such a setting. We compared the TAVR data at the University of South Dakota Sanford Medical Center to the national registry with the aim of looking at differences in outcomes of this procedure in a rural setting.

Use of Physician-Modified Endografts to Repair Unilateral or Bilateral Aortoiliac Aneurysms.

BACKGROUND: This article presents an endovascular approach to repair a unilateral or bilateral aortoiliac aneurysm with a bifurcated iliac limb that can maintain perfusion to the internal iliac artery (IIA) bilaterally through a brachial access. METHODS: A standard infrarenal aortic aneurysm repair is performed followed by iliac aneurysm exclusion. To obtain exclusion in the common iliac artery aneurysm, a bifurcated Endurant iliac limb is modified to compartmentalize iliac flow 2-3 cm above the internal iliac ostia. Then, a balloon-expandable covered stent graft is used to achieve sealing in the IIA and external iliac artery (EIA). The IIA is stented from the arm and the EIA is stented from the groin. RESULTS: There was no in-hospital or 30-day mortality. The procedural design was followed in each of the patients who received treatment. Technical success was 100%, short-term clinical success was 92%, and midterm clinical success was 83%. Average dosage of contrast medium was 116 mL (range, 55-193 mL), and average fluoroscopy time was 42.1 min (range, 20.8-91.6 min). Average length of hospital stay was 2.6 days (range, 1-9 days). There was 1 recorded endoleak. No reports of gluteal claudication, sexual dysfunction, or bowel or spinal claudication have been found. CONCLUSIONS: The technique described here does not require an up-and-over approach, allowing simplified bilateral repair. Although this is a promising technique, long-term durability needs to be evaluated in a controlled prospective study.

Safety and efficacy of ultrasound-accelerated catheter-directed lytic therapy in acute pulmonary embolism with and without hemodynamic instability.

OBJECTIVE: The objective of this study was to evaluate the safety and effectiveness of ultrasound-accelerated thrombolysis in acute pulmonary embolism. METHODS: A retrospective study of 45 patients was performed to evaluate treatment of acute pulmonary embolism at a single center from January 2011 to December 2013. All patients were diagnosed with computed tomography or ventilation-perfusion scan and had hemodynamic instability (systolic blood pressure <100 mm Hg) or right-sided heart strain evidenced by right ventricular dilation, septal deviation, or hypokinesis by echocardiography or computed tomography. EkoSonic catheters (EKOS Corporation, Bothell, Wash) were placed into the affected pulmonary arteries, and recombinant tissue plasminogen activator was infused through the catheters at 0.5 to 1.0 mg/h per catheter. RESULTS: Hypotension (systolic blood pressure <100 mm Hg) was present in 12 patients, with 100% resolution by treatment completion. Tachycardia (heart rate >100 beats/minute) was present in 26 patients and resolved in 92% by treatment completion; the average heart rate for all patients decreased from 109 to 77 beats/minute during the treatment period. Direct pulmonary artery pressure measurement showed average decrease of 21.5 mm Hg, representing a 40.2% reduction. Postprocedure echocardiography demonstrated complete resolution of cardiac dysfunction in 64%. Patients received a total dose of 30.5 mg (range, 14-66 mg) recombinant tissue plasminogen activator during an infusion time of 14.2 hours (range, 8-21 hours). There were no deaths through 90 days of follow-up and no major periprocedural bleeding events. CONCLUSIONS: This retrospective study demonstrates the safety and efficacy of current ultrasound-accelerated thrombolysis methods to treat acute pulmonary embolism.

Anatomic bifurcated reconstruction of chronic bilateral innominate-superior vena cava occlusion using the Y-stenting technique.

This article presents the case of a 42-year-old man who presented with superior vena cava (SVC) syndrome due to fibrosing mediastinitis with multiple failed attempts at recanalization. We initially treated him with unilateral sharp needle recanalization of the right innominate vein into the SVC stump followed by stenting. Although his symptoms improved immediately, they did not completely resolve. Six months later, he returned with worsening symptoms, and venography revealed in-stent restenosis. The patient requested simultaneous treatment on the left side. The right stent was dilated, and a 3-cm-long occlusion of the left innominate vein was recanalized, again using sharp needle technique, homing into the struts of the right-sided stent. Following fenestration of the stent, a second stent was deployed from the left side into the SVC, and the two Y limbs were sequentially dilated to allow a true bifurcation anatomy (figure). The patient had complete resolution of his symptoms and continues to do well 6 months later.

Hyaluronan mediates adhesion of metastatic colon carcinoma cells.

BACKGROUND: Hyaluronan (HA) is a cell-surface glycosaminoglycan that has been implicated in cancer progression. Cells isolated from metastatic colon carcinoma (SW620) produce greater amounts of pericellular HA than cells isolated from a primary tumor (SW480). Inhibition of hyaluronan synthases (HAS) by transfection with antisense cDNA decreases HA production. Because adhesion to the extracellular matrix (ECM) is required for invasion and metastasis, we hypothesized that pericellular HA mediates adhesion to ECM proteins such as laminin, collagen, and fibronectin and that inhibition of HA production or removal of HA by digestion with hyaluronidase would impair adhesion. MATERIALS AND METHODS: SW480, SW620, and antisense transfectants (SW620 cells transfected with vector alone, antisense HAS2, antisense HAS3, and both antisense HAS2 and HAS3) were assessed for adhesion to laminin, Type 1 collagen, or fibronectin-coated plates. To confirm that adhesion was mediated by HA, cells were treated with or without hyaluronidase prior to the assays. RESULTS: Metastatic SW620 cells adhered well to laminin; SW480 cells demonstrated 46% less adhesion (P < 0.05; Student's t test). SW620 cell adhesion to Type 1 collagen and fibronectin was >50% less than adhesion to laminin. Inhibition of HAS2 and/or HAS3 or pretreatment with hyaluronidase significantly decreased adhesion of SW620 cells to laminin (P < 0.05), suggesting that adhesion was dependent upon pericellular HA. CONCLUSIONS: Metastatic SW620 cells that produce large amounts of pericellular HA adhered well to laminin. Inhibition of HAS2 and/or HAS3 expression, or hyaluronidase digestion of pericellular HA significantly inhibited adhesion. These data suggest that HA promotes adhesion to laminin and may thereby facilitate invasion of the basement membrane and metastasis in colon carcinoma.