Optimization of duplex velocity criteria for diagnosis of internal carotid artery (ICA) stenosis: A report of the Intersocietal Accreditation Commission (IAC) Vascular Testing Division Carotid Diagnostic Criteria Committee.

Diagnostic criteria to classify severity of internal carotid artery (ICA) stenosis vary across vascular laboratories. Consensus-based criteria, proposed by the Society of Radiologists in Ultrasound in 2003 (SRUCC), have been broadly implemented but have not been adequately validated. We conducted a multicentered, retrospective correlative imaging study of duplex ultrasound versus catheter angiography for evaluation of severity of ICA stenosis. Velocity data were abstracted from bilateral duplex studies performed between 1/1/2009 and 12/31/2015 and studies were interpreted using SRUCC. Percentage ICA stenosis was determined using North American Symptomatic Carotid Endarterectomy Trial (NASCET) methodology. Receiver operating characteristic analysis evaluated the performance of SRUCC parameters compared with angiography. Of 448 ICA sides (from 224 patients), 299 ICA sides (from 167 patients) were included. Agreement between duplex ultrasound and angiography was moderate (κ = 0.42), with overestimation of degree of stenosis for both moderate (50-69%) and severe (⩾ 70%) ICA lesions. The primary SRUCC parameter for ⩾ 50% ICA stenosis of peak-systolic velocity (PSV) of ⩾ 125 cm/sec did not meet prespecified thresholds for adequate sensitivity, specificity, and accuracy (sensitivity 97.8%, specificity 64.2%, accuracy 74.5%). Test performance was improved by raising the PSV threshold to ⩾ 180 cm/sec (sensitivity 93.3%, specificity 81.6%, accuracy 85.2%) or by adding the additional parameter of ICA/common carotid artery (CCA) PSV ratio ⩾ 2.0 (sensitivity 94.3%, specificity 84.3%, accuracy 87.4%). For ⩾ 70% ICA stenosis, analysis was limited by a low number of cases with angiographically severe disease. Interpretation of carotid duplex examinations using SRUCC resulted in significant overestimation of severity of ICA stenosis when compared with angiography; raising the PSV threshold for ⩾ 50% ICA stenosis to ⩾ 180 cm/sec as a single parameter or requiring the ICA/CCA PSV ratio ⩾ 2.0 in addition to PSV of ⩾ 125 cm/sec for laboratories using the SRUCC is recommended to improve the accuracy of carotid duplex examinations.

Intersocietal Accreditation Commission Accreditation Status of Outpatient Cerebrovascular Testing Facilities Among Medicare Beneficiaries: The VALUE Study.

OBJECTIVES: Accreditation of cerebrovascular ultrasound laboratories by the Intersocietal Accreditation Commission (IAC) and equivalent organizations is supported by the Joint Commission certification of stroke centers. Limited information exists on the accreditation status and geographic distribution of cerebrovascular testing facilities in the United States. Our study objectives were to identify the proportion of IAC-accredited outpatient cerebrovascular testing facilities used by Medicare beneficiaries, describe their geographic distribution, and identify variations in cerebrovascular testing procedure types and volumes by accreditation status. METHODS: As part of the VALUE (Vascular Accreditation, Location, and Utilization Evaluation) Study, we examined the proportion of IAC-accredited facilities that conducted cerebrovascular testing in a 5% Centers for Medicare and Medicaid Services random Outpatient Limited Data Set in 2011 and investigated their geographic distribution using geocoding. RESULTS: Among 7327 outpatient facilities billing Medicare for cerebrovascular testing, only 22% (1640) were IAC accredited. The proportion of IAC-accredited cerebrovascular testing facilities varied by region (χ(2)[3] = 177.1; P < .0001), with 29%, 15%, 13%, and 10% located in the Northeast, South, Midwest, and West, respectively. However, of the total number of cerebrovascular outpatient procedures conducted in 2011 (38,555), 40% (15,410) were conducted in IAC-accredited facilities. Most cerebrovascular testing procedures were carotid duplex, with 40% of them conducted in IAC-accredited facilities. CONCLUSIONS: The proportion of facilities conducting outpatient cerebrovascular testing accredited by the IAC is low and varies by region. The growing number of certified stroke centers should be accompanied by more accredited outpatient vascular testing facilities, which could potentially improve the quality of stroke care.

Accreditation status and geographic location of outpatient vascular testing facilities among Medicare beneficiaries: the VALUE (Vascular Accreditation, Location & Utilization Evaluation) study.

OBJECTIVE: There is limited information on the accreditation status and geographic distribution of vascular testing facilities in the US. The Centers for Medicare & Medicaid Services (CMS) provide reimbursement to facilities regardless of accreditation status. The aims were to: (1) identify the proportion of Intersocietal Accreditation Commission (IAC) accredited vascular testing facilities in a 5% random national sample of Medicare beneficiaries receiving outpatient vascular testing services; (2) describe the geographic distribution of these facilities. METHODS: The VALUE (Vascular Accreditation, Location & Utilization Evaluation) Study examines the proportion of IAC accredited facilities providing vascular testing procedures nationally, and the geographic distribution and utilization of these facilities. The data set containing all facilities that billed Medicare for outpatient vascular testing services in 2011 (5% CMS Outpatient Limited Data Set (LDS) file) was examined, and locations of outpatient vascular testing facilities were obtained from the 2011 CMS/Medicare Provider of Services (POS) file. RESULTS: Of 13,462 total vascular testing facilities billing Medicare for vascular testing procedures in a 5% random Outpatient LDS for the US in 2011, 13% (n=1730) of facilities were IAC accredited. The percentage of IAC accredited vascular testing facilities in the LDS file varied significantly by US region, p<0.0001: 26%, 12%, 11%, and 7% for the Northeast, South, Midwest, and Western regions, respectively. CONCLUSIONS: Findings suggest that the proportion of outpatient vascular testing facilities that are IAC accredited is low and varies by region. Increasing the number of accredited vascular testing facilities to improve test quality is a hypothesis that should be tested in future research.

Venous disease in women: epidemiology, manifestations, and treatment.

Until the past decade, venous disease was commonly underdiagnosed and undertreated due to lack of interest on the part of providers and to reluctance to undergo procedures on the part of patients. Modern venous interventions, improved diagnostic modalities, and increased awareness through education, training, and screening programs have all raised enthusiasm for venous disease in recent years. This has been crucial to gain control over a disease that affects a significant proportion of the population, with women being affected more than men. This article will discuss epidemiologic studies that highlight some of the gender-related issues and review the risk factors for venous disease. We will also discuss the physiologic venous changes that occur with pregnancy and highlight functional venous disease in women. Finally, we will review the indications for and treatment of superficial venous disease.

Trends in a changing vascular practice environment for members of the Society for Vascular Surgery.

OBJECTIVE: To survey the Society for Vascular Surgery (SVS) membership with regard to practice trends related to work effort, employment status, practice ownership, endovascular cases, and anticipated changes in practice in the near future. METHODS: A survey questionnaire was developed to gather information about member demographics and practice, hours worked, full-time (FT) or part-time status, employment status, practice ownership, competition for referrals, proportion of endovascular vs open procedures, and anticipated changes in practice in the next 3 years. We used SurveyMonkey and distributed the survey to all active vascular surgeon (VS) members of the SVS. RESULTS: The response rate was 207 of 2230 (10.7%). Two thirds were in private practice, and 21% were in solo practice. Twenty-four percent were employed by hospitals/health systems. Those VS under the age of 50 years were more likely to exclusively practice vascular surgery compared with VS over the age of 50 years (P = .0003). Sixty-eight of the physicians (32.7%) were between 50 and 59 years old, 186 (90.3%) were men, 192 (92.8%) worked FT (>36 hours of patient care per week), and almost two thirds worked >60 hours per week. Those in physician-owned practices worked >40 hours of patient care per week more often than did FT employed VS (P = .012). Younger VS (age <50 years) more frequently reported >50% of their workload being endovascular compared with older VS (age ≥50 years; P < .001). Eighty percent of FT VS planned to continue their current practice over the next 3 years. Of the 43.6% indicating loss of referrals, 82% pointed to cardiologists as the competition. CONCLUSIONS: The current workforce is predominately male and works FT; one-third is between the ages of 50 and 59 years. Younger VS (age <50 years) are more likely to exclusively practice VS and have a higher caseload of endovascular procedures. Those in physician-owned practices are more likely to put in >40 hours of patient care per week than are FT employed VS. Longitudinal surveys of SVS members are imperative to help tailor educational, training, and practice management offerings, guide governmental activities, advocate for issues important to members, improve branding initiatives, and sponsor workforce analyses.

Early thrombus removal strategies for acute deep venous thrombosis: clinical practice guidelines of the Society for Vascular Surgery and the American Venous Forum.

BACKGROUND: The anticoagulant treatment of acute deep venous thrombosis (DVT) has been historically directed toward the prevention of recurrent venous thromboembolism. However, such treatment imperfectly protects against late manifestations of the postthrombotic syndrome. By restoring venous patency and preserving valvular function, early thrombus removal strategies can potentially decrease postthrombotic morbidity. OBJECTIVE: A committee of experts in venous disease was charged by the Society for Vascular Surgery and the American Venous Forum to develop evidence-based practice guidelines for early thrombus removal strategies, including catheter-directed pharmacologic thrombolysis, pharmacomechanical thrombolysis, and surgical thrombectomy. METHODS: Evidence-based recommendations are based on a systematic review and meta-analysis of the relevant literature, supplemented when necessary by less rigorous data. Recommendations are made according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, incorporating the strength of the recommendation (strong: 1; weak: 2) and an evaluation of the level of the evidence (A to C). RESULTS: On the basis of the best evidence currently available, we recommend against routine use of the term "proximal venous thrombosis" in favor of more precise characterization of thrombi as involving the iliofemoral or femoropopliteal venous segments (Grade 1A). We further suggest the use of early thrombus removal strategies in ambulatory patients with good functional capacity and a first episode of iliofemoral DVT of <14 days in duration (Grade 2C) and strongly recommend their use in patients with limb-threatening ischemia due to iliofemoral venous outflow obstruction (Grade 1A). We suggest pharmacomechanical strategies over catheter-directed pharmacologic thrombolysis alone if resources are available and that surgical thrombectomy be considered if thrombolytic therapy is contraindicated (Grade 2C). CONCLUSIONS: Most data regarding early thrombus removal strategies are of low quality but do suggest patient-important benefits with respect to reducing postthrombotic morbidity. We anticipate revision of these guidelines as additional evidence becomes available.

Validation of Venous Clinical Severity Score (VCSS) with other venous severity assessment tools from the American Venous Forum, National Venous Screening Program.

BACKGROUND: Several standard venous assessment tools have been used as independent determinants of venous disease severity, but correlation between these instruments as a global venous screening tool has not been tested. The scope of this study is to assess the validity of Venous Clinical Severity Scoring (VCSS) and its integration with other venous assessment tools as a global venous screening instrument. METHODS: The American Venous Forum (AVF), National Venous Screening Program (NVSP) data registry from 2007 to 2009 was queried for participants with complete datasets, including CEAP clinical staging, VCSS, modified Chronic Venous Insufficiency Quality of Life (CIVIQ) assessment, and venous ultrasound results. Statistical correlation trends were analyzed using Spearman's rank coefficient as related to VCSS. RESULTS: Five thousand eight hundred fourteen limbs in 2,907 participants were screened and included CEAP clinical stage C0: 26%; C1: 33%; C2: 24%; C3: 9%; C4: 7%; C5: 0.5%; C6: 0.2% (mean, 1.41 ± 1.22). VCSS mean score distribution (range, 0-3) for the entire cohort included: pain 1.01 ± 0.80, varicose veins 0.61 ± 0.84, edema 0.61 ± 0.81, pigmentation 0.15 ± 0.47, inflammation 0.07 ± 0.33, induration 0.04 ± 0.27, ulcer number 0.004 ± 0.081, ulcer size 0.007 ± 0.112, ulcer duration 0.007 ± 0.134, and compression 0.30 ± 0.81. Overall correlation between CEAP and VCSS was moderately strong (r(s) = 0.49; P < .0001), with highest correlation for attributes reflecting more advanced disease, including varicose vein (r(s) = 0.51; P < .0001), pigmentation (r(s) = 0.39; P < .0001), inflammation (r(s) = 0.28; P < .0001), induration (r(s) = 0.22; P < .0001), and edema (r(s) = 0.21; P < .0001). Based on the modified CIVIQ assessment, overall mean score for each general category included: Quality of Life (QoL)-Pain 6.04 ± 3.12 (range, 3-15), QoL-Functional 9.90 ± 5.32 (range, 5-25), and QoL-Social 5.41 ± 3.09 (range, 3-15). Overall correlation between CIVIQ and VCSS was moderately strong (r(s) = 0.43; P < .0001), with the highest correlation noted for pain (r(s) = 0.55; P < .0001) and edema (r(s) = 0.30; P < .0001). Based on screening venous ultrasound results, 38.1% of limbs had reflux and 1.5% obstruction in the femoral, saphenous, or popliteal vein segments. Correlation between overall venous ultrasound findings (reflux + obstruction) and VCSS was slightly positive (r(s) = 0.23; P < .0001) but was highest for varicose vein (r(s) = 0.32; P < .0001) and showed no correlation to swelling (r(s) = 0.06; P < .0001) and pain (r(s) = 0.003; P = .7947). CONCLUSIONS: While there is correlation between VCSS, CEAP, modified CIVIQ, and venous ultrasound findings, subgroup analysis indicates that this correlation is driven by different components of VCSS compared with the other venous assessment tools. This observation may reflect that VCSS has more global application in determining overall severity of venous disease, while at the same time highlighting the strengths of the other venous assessment tools.

The care of patients with varicose veins and associated chronic venous diseases: clinical practice guidelines of the Society for Vascular Surgery and the American Venous Forum.

The Society for Vascular Surgery (SVS) and the American Venous Forum (AVF) have developed clinical practice guidelines for the care of patients with varicose veins of the lower limbs and pelvis. The document also includes recommendations on the management of superficial and perforating vein incompetence in patients with associated, more advanced chronic venous diseases (CVDs), including edema, skin changes, or venous ulcers. Recommendations of the Venous Guideline Committee are based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system as strong (GRADE 1) if the benefits clearly outweigh the risks, burden, and costs. The suggestions are weak (GRADE 2) if the benefits are closely balanced with risks and burden. The level of available evidence to support the evaluation or treatment can be of high (A), medium (B), or low or very low (C) quality. The key recommendations of these guidelines are: We recommend that in patients with varicose veins or more severe CVD, a complete history and detailed physical examination are complemented by duplex ultrasound scanning of the deep and superficial veins (GRADE 1A). We recommend that the CEAP classification is used for patients with CVD (GRADE 1A) and that the revised Venous Clinical Severity Score is used to assess treatment outcome (GRADE 1B). We suggest compression therapy for patients with symptomatic varicose veins (GRADE 2C) but recommend against compression therapy as the primary treatment if the patient is a candidate for saphenous vein ablation (GRADE 1B). We recommend compression therapy as the primary treatment to aid healing of venous ulceration (GRADE 1B). To decrease the recurrence of venous ulcers, we recommend ablation of the incompetent superficial veins in addition to compression therapy (GRADE 1A). For treatment of the incompetent great saphenous vein (GSV), we recommend endovenous thermal ablation (radiofrequency or laser) rather than high ligation and inversion stripping of the saphenous vein to the level of the knee (GRADE 1B). We recommend phlebectomy or sclerotherapy to treat varicose tributaries (GRADE 1B) and suggest foam sclerotherapy as an option for the treatment of the incompetent saphenous vein (GRADE 2C). We recommend against selective treatment of perforating vein incompetence in patients with simple varicose veins (CEAP class C(2); GRADE 1B), but we suggest treatment of pathologic perforating veins (outward flow duration ≥500 ms, vein diameter ≥3.5 mm) located underneath healed or active ulcers (CEAP class C(5)-C(6); GRADE 2B). We suggest treatment of pelvic congestion syndrome and pelvic varices with coil embolization, plugs, or transcatheter sclerotherapy, used alone or together (GRADE 2B).

Call to action to prevent venous thromboembolism.

Deep venous thrombosis and pulmonary embolism, together called venous thromboembolism, remain a serious national health problem. Estimates suggest that over 900,000 cases occur in the United States per year, with 300,000 deaths per year. Because of the significant and serious nature of this problem, a workshop was held in May of 2006, which resulted in the Acting U.S. Public Health Service Surgeon General's Call to Action to Prevent Deep Vein Thrombosis and Pulmonary Embolism. On September 15, 2008, Acting Surgeon General, Rear Admiral Steven K. Galson, MD, MPH, and Elizabeth Nabel, MD, Director National Heart, Lung, and Blood Institute, announced the Call to Action. The Call to Action highlights public awareness about the risk factors, triggering events, and symptoms of venous thrombosis and pulmonary embolism, and encourages the development of evidence based practices for screening, prevention, diagnosis, and treatment of venous thrombosis and pulmonary embolism. It is designed to encourage new scientific investigation in an effort to obtain needed evidence to fill in the gaps of knowledge about venous thrombosis and pulmonary embolism. This knowledge should be quickly and easily disseminated to the public and put into practice by health professionals. The Surgeon General's Call to Action represents one of the most important advances in the field of venous thromboembolism and sets the stage for multidisciplinary efforts to combat this serious national health problem.

Clinical benefit of carotid endarterectomy based on duplex ultrasonography.

Carotid endarterectomy has been shown to significantly reduce the risk of stroke caused by carotid artery stenosis in selected patients. Limiting the morbidity and costs of this process without increasing the risks should further improve the benefits of this procedure. Results were prospectively collected from 123 consecutive carotid endarterectomies performed at a community teaching hospital. All patients underwent duplex ultrasonography for preoperative evaluation. Catheter angiography was used on a selective basis. Preferential use of regional anesthetic and selective use of the intensive care unit were applied. The mortality, morbidity, complications, and costs were then compared for the group receiving only preoperative duplex ultrasonography with those undergoing catheter angiography preoperatively. Age, comorbid risk factors, indications for carotid endarterectomy, and incidence of stroke were similar in both patient groups. The rates of mortality, morbidity, and stroke for carotid endarterectomy were low (mortality 0%, morbidity 6.5%, stroke 0.8%). For preoperative evaluation all patients underwent duplex ultrasonography (100%) and 28 (23%) underwent preoperative catheter angiography in addition to duplex ultrasonography. The complication rate associated with catheter angiography was 6/28 (21%). Complications included groin hematoma (7%), pseudoaneurysm (3.6%), bradycardia (7%), and unstable angina (3.6%). Costs for duplex ultrasonography averaged 165 US dollars and additional costs incurred by the use of catheter angiography averaged 4,200 US dollars. Intraoperative assessment of the carotid endarterectomy site did not change based on the use of preoperative catheter angiography. Morbidity, mortality, and stroke rates were the same for the 2 groups. The preoperative use of duplex ultrasonography for the sole evaluation in carotid endarterectomy is well established. The use of preoperative catheter angiography is still preferred by a subset of surgeons. The use of catheter angiography is associated with significant morbidity and additional costs when compared to performing carotid endarterectomy based solely on preoperative duplex ultrasonography. The added costs and morbidity of angiography increase the societal cost of this procedure without significant clinical improvement in patient outcome.

Retained wireless video enteroscopy capsule: a case report and review of the literature.

Capsule enteroscopy, which is a wireless noninvasive approach to evaluation of the small intestine, consists of an 11 x 26-mm capsule containing a miniature video camera, batteries, illuminating light-emitting diodes, a transmitter, and an antenna. The components inside the capsule are encased by a slippery, nonbiodegradable, plastic housing, which weighs less than 4 g. Information obtained from the imager, approximately 2 frames per second, is transmitted by way of radiotelemetry to an array of sensors taped to the abdomen, which connect to a data recorder worn on a belt around the waist. The batteries are designed to last roughly 7-8 hours, providing enough energy to generate approximately 50,000 to 60,000 detailed images. The clinical review of the imagery is made available after completion of the study when images are downloaded from the data recorder to a computer with dedicated software.

The hemodynamics and diagnosis of venous disease.

The venous system is, in many respects, more complex than the arterial system and a thorough understanding of venous anatomy, pathophysiology, and available diagnostic tests is required in the management of acute and chronic venous disorders. The venous system develops through several stages, which may be associated with a number of development anomalies. A thorough knowledge of lower extremity venous anatomy, anatomic variants, and the recently updated nomenclature is required of all venous practitioners. Effective venous return from the lower extremities requires the interaction of the heart, a pressure gradient, the peripheral muscle pumps of the leg, and competent venous valves. In the absence of pathology, this system functions to reduce venous pressure from approximately 100 mm Hg to a mean of 22 mm Hg within a few steps. The severe manifestations of chronic venous insufficiency result from ambulatory venous hypertension, or a failure to reduce venous pressure with exercise. Although the precise mechanism remains unclear, venous hypertension is thought to induce the associated skin changes through a number of inflammatory mechanisms. Several diagnostic tests are available for the evaluation of acute and chronic venous disease. Although venous duplex ultrasonography has become the standard for detection of acute deep venous thrombosis, adjuvant modalities such as contrast, computed tomographic, and magnetic resonance venography have an increasing role. Duplex ultrasonography is also the most useful test for detecting and localizing chronic venous obstruction and valvular incompetence. However, it provides relatively little quantitative hemodynamic information and is often combined with measurements of hemodynamic severity determined by a number of plethysmographic methods. Finally, critical assessment of venous treatment modalities requires an understanding of the objective clinical outcome and quality of life instruments available.