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Nicos Labropoulos

Publications and source records attributed to Nicos Labropoulos.

At least 19 recordsLinked to original sources

Free-floating thrombus of the carotid artery: literature review and case reports.

BACKGROUND: Free-floating thrombus (FFT) of the carotid artery is an uncommon entity that usually presents as an acute emergency. Management is based on case reports and series because the natural history and optimal treatment are unknown. This study was conducted to systematically review the world literature in an attempt to better understand FFT, its presentation, distribution, management, and outcome. METHOD: A literature search in all languages was performed of the PubMed database (> or =1950s) and Medline database (1966-November 2004). All relevant articles were reviewed and their references analyzed in a similar manner for further literature. Cases from the authors' institutions were reviewed as well. All cases within the reports were individually assessed for inclusion or exclusion. Inclusion required that the FFT originate or anchor within the carotid artery (ie, excluding emboli, arch thrombi with extensions into the carotid artery), be partially occluding (ie, excluding occlusions, "string-sign," microscopic thrombus), and ideally have an elongated or protrusive morphology, circumferential flow around the distal portion, and cyclical motion with the cardiac cycles. RESULTS: There were 61 reports reviewed, of which 43 contained FFT cases. These reports had 342 cases (including the current series) that were reviewed, of which 145 met our inclusion criteria. A database was created for qualitative and quantitative assessment of all cases. When data were pooled, appropriate statistical analysis was performed. A limitation of the study is that FFT is under-reported and ill defined, which limited the analysis in quantity and quality. In addition, reporting is not uniform, and therefore, significant data were not always present. In attempting to define FFT and include or exclude cases, subjectivity is inherent. CONCLUSIONS: FFT is more frequently reported in men than women, with a ratio of nearly 2:1 (P < .0001), and at a younger age than in most patients with carotid disease (P < .0001 when compared with North American Symptomatic Carotid Endarterectomy Trial, European Carotid Surgery Trial, and Asymptomatic Carotid Surgery Trial). Symptoms are present in 92% of patients. There was a trend for patients with FFT to be hypercoagulable (47% of those serologically tested). The internal carotid artery was the most commonly affected (75%), with atherosclerosis being the most common associated pathology. Medical and surgical management have both been used, with neither clearly superior to the other. Medical management for stabilizing neurologic deficits has less risk and less benefit than surgical intervention.

Angiography↗

Excision of internal jugular vein for catheter-related thrombophlebitis.

This report describes a case of internal jugular vein (IJV) thrombophlebitis refractory to intravenous (IV) antibiotics and anticoagulation managed with ligation and excision of the vein. Our patient was immunosuppressed for a transplanted organ and developed a catheter-related infection following major pelvic surgery. His symptoms worsened, and failure of medical management prompted operative intervention. Excision of the inflamed, thrombosed vein led to complete resolution of his symptoms.

Catheterization, Central Venous↗

Presentation of the patient with recurrent varices after surgery (REVAS).

AIM: To identify in patients with recurrent varices after surgery (REVAS) the clinical, etiologic, anatomic, and pathophysiologic patterns according to the CEAP classification, as well as the site, source, causes of recurrence, and contributory factors by using the REVAS classification. METHODS: Centers from eight countries enrolled patients with superficial vein reflux that had had a previous operation. A physical examination and a duplex ultrasound scan were performed at the first visit. This was repeated between 2 to 8 weeks after by the same physician and by another physician within the same time frame. The perforator, deep, and superficial veins systems as well as their accessories and tributaries were examined. A form based on the CEAP and the REVAS classification was used and the data were entered in a customized database. RESULTS: Fourteen institutions enrolled 170 patients (199 lower limbs) in 1 year. Their mean age was 56 years, and 69% were women. Most of them had undergone one surgical procedure before enrollment (76.6%). Most had varicose veins and swelling (70.9%), and the rest had skin damage (29.1%). More than 90% had primary etiology. The saphenofemoral junction (47.2%) and leg perforators (54.7%) were the areas most often involved by recurrent reflux. Reflux in deep veins was detected in 27.4%. Class 2 (varicose veins) alone was present in 24.6% of limbs, two classes were present in 43%, and three in 24%. Neovascularization was as frequent as technical failure (20% vs 19%); both were seen in 17%. In 35%, the cause was uncertain or unknown. When recurrence occurred at a different site, development of reflux in new sites was found in 32% of limbs. Of the contributing factors, family history and lifestyle had the highest prevalence. Women had significantly more procedures than men, despite a clear trend toward more severe disease in the latter. CONCLUSIONS: Most patients were symptomatic with several clinical forms of presentation. The REVAS classification, together with CEAP, gives significant and more appropriate information for evaluating and following-up patients with chronic venous disease who have had an intervention.

Adult↗

Development of reflux in the perforator veins in limbs with primary venous disease.

OBJECTIVE: To determine the patterns by which perforator vein (PV) reflux develops in patients with primary chronic venous disease (CVD). METHODS: Patients with CVD who had at least two examinations with duplex ultrasonography before any treatment were included in this study. These were patients who were offered an operation at their first visit, but for various reasons treatment was postponed. All affected limbs were classified by the CEAP classification system. A detailed map of normal and refluxing sites was drawn on an anatomic chart by using several landmarks of the skin, muscle, and bone. Reflux was induced by distal limb compression followed by sudden release by using rapid-inflation pneumatic cuffs and dorsiplantar flexion. All new reflux sites were documented. The PV reflux was divided into ascending type, descending type (re-entry flow), and those that developed in new locations, which did not have reflux in any system at that level. RESULTS: The total number of patients studied was 127 (158 limbs). There were 29 limbs (18%) in 26 patients with reflux development in the PV. In total, 38 new incompetent PVs were identified. The median time for the examination was 25 months (range, 9-52 months). Reflux in a previously normal PV at a re-entry site was detected in 15, in an ascending manner from an extension of superficial vein reflux in 18, and in a new, previously intact location in 5. At the new sites, reflux in the superficial veins connected to the incompetent PVs was always present. PVs connected to the great saphenous vein system were most common (n = 27), followed by those connected to short saphenous (n = 8) and nonsaphenous (n = 3) veins. Worsening in the clinical class was observed in 11 limbs: 5 from class 2 to 3, 2 from class 2 to 4, 2 from class 3 to 4, and 2 from class 4 to 6. The worsening could not be attributed to the PV reflux alone, because other veins became incompetent as well. CONCLUSIONS: Reflux in PVs develops in ascending fashion through the superficial veins, at re-entry points, and at new sites. Worsening of CVD is observed with new PV reflux, but many other factors play a major role, and therefore a causative association is difficult to prove.

Chronic Disease↗

Current management of venous ulceration.

It has been estimated that chronic venous insufficiency affects 10 to 35 percent of the entire U.S. population and that 4 percent of people older than 65 have active venous ulcers. The high prevalence of the disease results in an annual expenditure of more than 1 billion dollars a year to the U.S. health care system. To have a rational approach toward patients with venous ulcers, it is important to understand the pathophysiology and clinical characteristics of the disease process, in order to initiate appropriate treatment and prevent venous ulcer recurrence.

Adult↗

The issue of spontaneous arteriovenous fistulae after superficial thrombophlebitis, endovenous ablations, and deep vein thrombosis: an unusual but predictable finding.

Spontaneous arteriovenous fistulae develop after the formation of venous thrombi in animals. In patients who have undergone endovenous ablation, angiogenesis occurs. This study was undertaken to examine the clinical presentation, development, and effects of spontaneous arteriovenous fistulae in patients with venous thrombosis.

Arteriovenous Fistula↗

The prophylactic use of inferior vena cava filters in patients undergoing high-risk spinal surgery.

Prophylactic inferior vena cava filter (IVCF) placement is advocated in some high-risk groups. We sought data regarding safety and efficacy for prophylactic IVCF placement in patients at high risk for venous thromboembolism (VTE) following major spinal reconstruction. Seventy-four spine surgery patients with contraindication to anticoagulation (44 females, 30 males; mean age 56.2) received prophylactic IVCFs. Criteria were (1) history of thromboembolism, (2) diagnosed thrombophilia, (3) malignancy, (4) bedridden >2 weeks prior to surgery, (5) staged procedures or multiple levels, (6) combined anterior/posterior approaches, (7) expected need for significant iliocaval manipulation during exposure, and (8) single-stage anesthetic time >8 hr. Seventy patients had at least two risk factors. All received IVCFs prior to the first stage of spine reconstruction. Patients were evaluated for filter complications, deep vein thrombosis (DVT), and pulmonary embolism (PE). Patients' lower extremity veins from groin to ankle were imaged weekly until discharge using duplex ultrasound (DUS). One-third also underwent thoracic and pelvic computed tomography scans, and the pelvic veins, IVC, and pulmonary vasculature were evaluated for VTE. Multiple DUS (n = 198, mean 2.6 studies per patient) were performed in 68 patients. At a mean follow-up of 11 months, one of the patients developed PE. Twenty-seven limbs in 23 patients developed DVT. Five limbs had isolated calf DVT, and 22 had proximal vein involvement. Insertion site DVT accounted for nearly one-third of the DVTs. Six patients died from unrelated complications. There was one technical error with an IVCF deployed in the iliac vein. Despite a high incidence of DVT following high-risk spinal surgery, prophylactic IVCF placement appears to protect patients from PE.

Adolescent↗

Non-invasive cardiovascular risk assessment in women with type 2 diabetes.

This study assessed and compared carotid intima-media thickness (IMT) in postmenopausal women with type 2 diabetes with that in postmenopausal women without type 2 diabetes and compared risk factors that contribute to increased carotid IMT in these groups of women. Carotid IMT, a non-invasive assessment of cardiovascular risk, was measured using high-resolution ultrasound in 20 postmenopausal women with type 2 diabetes and 20 postmenopausal women without type 2 diabetes who had no known coronary heart disease. Risk factors (age, race, family history, diabetes, hypertension, high cholesterol, years past menopause, use of hormone replacement therapy, perceived level of physical activity, and body mass index) known to contribute to coronary heart disease were also assessed. Mean carotid IMT was .88 mm for women with type 2 diabetes compared with .74 mm for women without type 2 diabetes. There were no differences between groups in age, race, cholesterol, and perceived level of physical activity. Women with type 2 diabetes, however, reported more hypertension ( P = .004), greater body mass index ( P = .026), and less use of hormone replacement therapy ( P = .027). Of concern is that 10% of the women with diabetes had stenosis that required surgical intervention. Findings suggest that carotid IMT is a valid way to screen for cardiovascular risk, particularly in postmenopausal women who are at high risk for coronary heart disease. It may also be a feasible, non-invasive method for the detection and prevention of the macrovascular complications of diabetes.

Body Mass Index↗

Study of the venous reflux progression.

BACKGROUND: Patients with chronic venous disease (CVD) often ask whether elective vein surgery could be delayed without consequences. Because the natural history of CVD is not well known, this study was designed to determine its progression in such patients. METHODS: One hundred and sixteen limbs in 90 patients who had at least 2 exams with duplex ultrasound (DU) scanning prior to vein surgery at a university medical center were studied. These were patients who were offered an operation but for various reasons were treated at a later stage. Patients were classified by the CEAP system. RESULTS: The mean age of the patients was 49 years (range, 23 to 81 years). A second DU scan was performed 1 to 43 months after the initial exam (median, 19 months). Eighty-five limbs (73.3%) were unchanged. Thirteen limbs (11.2%) had progression of clinical stage, and seven had progression on DU scanning as well. Seven limbs progressed from C2 to C3, four limbs from C3 to C4, and two limbs from C4 to C6. Thirty-four limbs had a documented change on repeat DU scanning. In 3 of these limbs, reflux was missed on the initial exam; therefore, 31 limbs had progression of disease. The great saphenous vein and tributaries were the most often anatomic sites affected by a change, followed by perforators. Seventeen limbs (14.7%) had extension of pre-existing reflux, and 14 (12.1%) had reflux in a new segment. In 11 of these limbs, a change in the initial plan for treatment was required. Symptomatic or DU changes were noted 6 months or later in 95% of limbs and 74.2% of limbs with disease progression were diagnosed at 12 months or later. All but one of the 13 symptomatic limbs developed symptoms at least a year later. CONCLUSION: Nearly one third of patients with venous reflux had progression. Anatomic extension is frequent with disease progression but not a pre-requisite. Progression was found in most limbs 6 months after the initial study. Patients undergoing treatment for their veins may need another DU exam if this time interval is exceeded.

Adult↗

To what extent has endovascular aneurysm repair influenced abdominal aortic aneurysm management in the state of Illinois?

PURPOSE: This study was performed using population-based data to determine the changing trends in the techniques for abdominal aortic aneurysm (AAA) repair in the state of Illinois during the past 9 years and to examine the extent to which endovascular aneurysm repair (EVAR) has influenced overall AAA management. METHODS: All records of patients who underwent AAA repair (1995 to 2003 inclusive) were retrieved from the Illinois Hospital Association COMPdata database. The outcome as determined by in-hospital mortality was analyzed according to intervention type (open vs EVAR) and indication (elective repair vs ruptured AAA). Data were stratified by age, gender, and hospital type (university vs community setting) and then analyzed using both univariate (chi 2 , t tests) and multivariate (stepwise logistic regression) techniques. RESULTS: Between 1995 and 2003, 14,517 patients underwent AAA repair (85% for elective and 15% for ruptured AAA). The average age was 71.4 +/- 7.9 years, and 76% were men. For elective cases, open repair was performed in 86% and EVAR in 14%; and for ruptured cases, open repair in 97% and EVAR in 3%. Elective EVAR was associated with lower in-hospital mortality compared with open repair regardless of age. No differences were observed with age after either type of repair for a ruptured aneurysm. Men had a lower in-hospital mortality compared with women for open repair of both elective and ruptured aneurysms. For EVAR, the mortality of an elective repair was lower in men, but there was no difference after a ruptured AAA. In men, the difference in mortality between elective open repair and EVAR was significant; the type of institution did not influence outcome. Patients >80 years of age had a higher mortality after open repair for both elective and ruptured AAA and after EVAR of a ruptured AAA. The average length of stay was 9.9 days for open elective repair, 13.1 days after open repair of a ruptured AAA, and 3.6 days for EVAR. The independent predictors of higher in-hospital mortality were female gender, age >80 years, diagnosis (ruptured vs open), and procedure (open vs EVAR). The year of the procedure and type of hospital (university vs community) were not predictive of outcome. CONCLUSIONS: EVAR has had a significant impact on AAA management in Illinois over a relatively short time period. In this population-based review, EVAR was associated with a significantly decreased in-hospital mortality and length of stay. Octogenarians had higher mortality after both types of repair, with the exception of elective EVAR.

Age Factors↗

Neovascularization in acute venous thrombosis.

OBJECTIVE: The aim of this study was to describe the phenomenon of arteriovenous fistula (AVF) formation in venous thrombus. METHODS: Patients referred to the vascular laboratory for evaluation for deep venous thrombosis were included. Duplex ultrasound scanning was used to detect flow within the thrombus. The flow patterns and the resistivity index were obtained in the veins above/proximal and below/distal to the thrombus, in the adjacent arteries, and within the perivenous vessels. Patients with trauma, hemodialysis access, endovenous ablation, known AVF, or inflammatory conditions were excluded. RESULTS: There were 22 patients with AVF flow in thrombosed veins. Deep veins were involved in 15 cases and superficial veins in the remainder. Perivenous vessels feeding the AVF in the thrombus could be clearly identified in 16 patients (19 vein segments). In 21 of 22 patients, multiple flow channels were present throughout the involved thrombosed vein segment. These flow channels were isolated to a single vein segment. They measured <4 cm in length in 19 cases and were more extensive in the remaining three. Reflux within the vein segment was identified in 13 cases. Local symptoms that could be attributed to the arterialization of thrombosed veins occurred in four cases, and none of the patients manifested systemic symptoms. The flow within the thrombus had high end-diastolic velocities with a mean resistivity index of 0.48 (SD, 0.08), which is typical of a fistula flow pattern. The flow in the main arteries was unaffected. CONCLUSION: Neovessels were found with AVF flow in thrombi of superficial and deep veins. They had variable length and multiple flow channels, with inflow from perivenous arteries. The flow in the adjacent main arteries was not affected, and no systemic symptoms were detected. The exact etiology and natural history of this phenomenon are not known, and its clinical significance is unclear.

Adult↗

Hemodynamic effects of intermittent pneumatic compression in patients with critical limb ischemia.

BACKGROUND: Traditional teaching assumes that the distal arterial tree is maximally dilated in patients with critical limb ischemia (CLI). Endovascular or arterial bypass procedures are the commonly used interventions to increase distal perfusion. However, other forms of treatment such as spinal cord stimulation or intermittent pneumatic compression (IPC) have been shown to improve limb salvage rates. This prospective study was designed to determine if the use of IPC increases popliteal, gastrocnemial, collateral arterial, and skin blood flow in patients with CLI. METHODS: Twenty limbs with CLI in 20 patients (mean age, 74 years) were evaluated with duplex ultrasound scans and laser Doppler fluxmetry in the semi-erect position before, during, and after IPC. One pneumatic cuff was applied on the foot and the other on the calf. The maximum inflation pressure was 120 mm Hg and was applied for 3 seconds at three cycles per minute. All patients had at least two-level disease by arteriography. Fourteen limbs were characterized as inoperable, and six were considered marginal for reconstruction. Flow volumes were measured in the popliteal, medial gastrocnemial, and a genicular collateral artery. Skin blood flux was measured on the dorsum of the foot at the same time. RESULTS: Significant flow increase during the application of IPC was found in all three arteries (18/20 limbs) compared with baseline values (P < .02). The highest change was seen in the popliteal, followed by the gastrocnemial and the collateral artery. After the cessation of IPC, the flow returned to baseline. This was attributed to the elevation of time average velocity, as the diameter of the arteries remained unchanged. The skin blood flux increased significantly as well (P < .03). In the two limbs without an increase in the arterial or skin blood flow, significant popliteal vein reflux was found. Both limbs were amputated shortly after. CONCLUSIONS: IPC increases axial, muscular, collateral, and skin blood flow in patients with CLI and may be beneficial to those who are not candidates for revascularization. Patients with significant venous reflux may not benefit from IPC. This supports the theory that one of the mechanisms by which IPC enhances flow is by increasing the arteriovenous pressure gradient.

Aged↗

Duplex evaluation of venous insufficiency.

Duplex ultrasound is the most useful examination for the evaluation of venous valvular incompetence. Multi-frequency 4 to 7-MHz linear array transducers are typically used for this assessment of superficial and deep reflux. The examination is done with the patient standing and manual compression maneuvers are used to initiate reflux. Automatic rapid inflation and deflation cuffs may be used when a standard stimulus is needed. Cutoff values for reflux have been defined. Perforating veins must be identified and flow direction during compression recorded. When ulcers are present, duplex ultrasound is used to investigate veins of the ulcerated legs. Venous outflow obstruction is also studied by duplex ultrasound and chronic changes in deep and superficial veins following deep venous thrombosis noted. The main drawback in evaluation of chronic obstruction is inability to quantify hemodynamic significance. Anatomic variations in superficial and deep veins are common and their identification is necessary. Reporting results of duplex ultrasound studies must take into consideration the proper classification of venous disease as well as the new anatomic terms that have been accepted.

Humans↗

Superficial vein thrombosis and hypercoagulable states: the evidence.

AIM: To assess the demographic features of superficial vein thrombosis and its relation with the occurrence of hypercoagulable states. METHODS: Data were gathered from pertinent papers using a MEDLINE search and an exhaustive bibliography review. Studies were considered only when they contained material to superficial vein thrombosis and hypercoagulable states. RESULTS: The difference among the patients and the methods used made the comparison difficult and did not allow a pool analysis of the data. Superficial vein thrombosis is a common condition, and its prevalence is underestimated. Several risk factors are associated with superficial vein thrombosis, and a strong relation was seen with certain thrombophilias. CONCLUSIONS: Although superficial vein thrombosis most often is perceived as benign, it can coexist with hypercoagulable states. In patients with spontaneous onset of superficial vein thrombosis, there should be a lower threshold in testing for hypercoagulable states.

Comorbidity↗

The vascular surgeon's role in risk factor modification: results of a survey.

PURPOSE: Comprehensive care of vascular patients includes attention to atherosclerotic risk factor management. We surveyed members of the Midwestern Vascular Surgical Society (MVSS) with the following objectives: (1) to determine the usual practice pattern with respect to risk factor inquiry, screening, and intervention, (2) to determine which risk factors vascular surgeons believe are important for patients with peripheral arterial disease, and (3) to determine the vascular surgeon's confidence for management of each risk factor. METHODS: A survey was mailed to all MVSS members and two additional notifications were sent for initial nonresponders. Data regarding practice environment and local resources available to each surgeon were recorded. Questions were designed to determine the prevalence of risk factor inquiry and screening, grading of the importance of each risk factor, and the vascular surgeon's confidence in the management of each risk factor. RESULTS: The survey was completed by 219 (56%) of 391 of MVSS members. The average age of the responders was 53.1 +/- 9.3 years, and 94.1% were men. Seventy-four percent of the surgeons dedicate 90% to 100% of their time to vascular surgery, and 89% dedicate more than 50%. Seventy-seven percent of responders work in a private institution and 23% in a public hospital. The surgeon's practice had a full- or part-time affiliation with a medical school in 62% and was entirely community-based in 38%. A high proportion of surgeons inquire about each risk factor, but only a minority performs the actual screening of the risk factors, with the exception of hypertension. Diabetes mellitus and smoking were believed to be very important risk factors, hypertension and lipids of moderate importance, and exercise and activity, nutrition, and homocysteine level of low importance. The surgeons' confidence in risk factor management was low to moderate for most risk factors, but high for smoking and exercise. Despite these responses, only 10% of vascular surgeons thought that they should be primarily responsible for risk factor management. CONCLUSIONS: Vascular surgeons must provide a comprehensive approach to risk factor management for their patients. This can be conducted through the establishment of multidisciplinary risk factor programs or by the surgeon in certain cases when outside resources are not available. Risk factor management must be emphasized in vascular continuing medical education programs to enable surgeons to be confident with management.

Arteriosclerosis↗

Arteriovenous access: managing common problems.

The creation and maintenance of hemoaccess occupies a significant portion of most vascular and general surgery practices. In this article, the methods used to detect hemoaccess at risk for failure and the endovascular and surgical techniques used to prolong or restore their patency are reviewed. Also, the management of hemoaccess infection, aneurysmal degeneration, false aneurysm formation, and symptomatic arterial steal syndrome are described.

Aneurysm, False↗