Absence Of Deep Venous Thrombosis Research Articles

In Situ Pulmonary Arterial Thrombosis-Literature Review and Clinical Significance of a Distinct Entity.

Please see the Editorial Comment by Andetta Hunsaker discussing this article. Filling defects identified in the pulmonary arterial tree are commonly presumed to represent an embolic phenomenon originating from thrombi formed in remote veins, particularly lower-extremity deep venous thrombosis (DVT). However, accumulating evidence supports an underappreciated cause for pulmonary arterial thrombosis (PAT), namely, de novo thrombogenesis-where thrombosis arises within the pulmonary arteries in the absence of DVT. Although historically underrecognized, in situ PAT has become of heightened importance with the emergence of SARS-CoV-2 infection. In situ PAT is attributed to endothelial dysfunction, systemic inflammation, and acute lung injury, and has been described in a range of conditions including COVID-19, trauma, acute chest syndrome in sickle cell disease, pulmonary infections, and severe pulmonary arterial hypertension. The distinction between pulmonary embolus and in situ PAT may have important implications regarding management decisions and clinical outcomes. In this review, we summarize the pathophysiology, imaging appearances, and management of in situ PAT in various clinical situations. This understanding will promote optimal tailored treatment strategies for this increasingly recognized entity.

Abstract No. 609 Quality of life metrics in a young population with nonthrombotic iliac vein compression following stenting of the iliac vein

Data supporting stenting of iliac vein compression for deep venous thrombosis (DVT) has been widely accepted (1). In the past several years indications have expanded to include a myriad of symptoms surrounding chronic pelvic pain. While expanding, data to support stenting for these indications is still limited (2-5). In the absence of DVT, stenting young patients has been further avoided due to lack of long-term outcome data and concern for potential stent failure/complications over time. The main objective of this study is to introduce quality of life outcomes (QOL) after treatment of nonthrombotic iliac vein compression in patients 25 years and under for chronic pelvic pain.

Systemic consequences and clinical aspects of SARS-CoV-2 infection

HintergrundCOVID-19 wird als systemische Erkrankung eingestuft. Ein schwerer Verlauf mit tödlichem Ausgang ist möglich und unvorhersehbar.FragestellungWelche Organsysteme sind primär betroffen? Welche Organveränderungen prädisponieren für einen ungünstigen Verlauf? Welche Organschädigungen finden sich bei letalem Ausgang?Material und MethodeDaten aus publizierten Obduktionsstudien (davon 28 eigene publizierte Fälle) in Hinblick auf Organschädigung und mögliche Todesursachen.ErgebnisseDie schwersten Veränderungen finden sich in den Lungen in Form eines diffusen Alveolarschadens als akutes Atemnotsyndrom des Erwachsenen (ARDS), zum Teil bereits mit Fibrose. Thrombosen in kleinen bis mittelgroßen Pulmonalarterien sind mit Lungeninfarkten vergesellschaftet. Häufige Komplikationen sind bakterielle Bronchopneumonien, seltener Pilzpneumonien. Pulmonale Thromboembolien finden sich in 20–30 % der tödlichen Verläufe, auch bei Fehlen einer tiefen Beinvenenthrombose. Eine intestinale Beteiligung von COVID-19 kann mit ischämischer Schädigung des Darmes einhergehen, in erster Linie bedingt durch Schock oder lokale Thrombose. Die Nieren zeigen eine akute Tubulusschädigung als Ausdruck eines akuten Nierenversagens, Lymphknoten und Milz einen Schwund der Lymphozyten, die Nebennierenrinde eine Hyperplasie. In der Leber finden sich häufig eine Steatose, Leberzellnekrosen, ein portales Entzündungsinfiltrat und eine Proliferation der Kupffer-Zellen. Häufige Grunderkrankungen sind in den Autopsiekollektiven arterieller Hypertonus mit hypertensiver und ischämischer Kardiomyopathie und Diabetes mellitus. In großen bevölkerungsbasierten Studien ergibt sich aber für Hypertoniker im Gegensatz zu Diabetikern kein erhöhtes Mortalitätsrisiko.SchlussfolgerungenPulmonale Kreislaufstörungen mit arteriellen Thrombosen, Infarkten und Pneumonien sind wesentliche und oft letale Komplikationen des ARDS bei COVID-19. Die Erkenntnisse aus Obduktionsstudien haben Therapie und Prophylaxe beeinflusst.

Incidence of deep venous thrombosis in patients with both Pulmonary Embolism and COPD.

Introduction.There are no studies investigating populations of patients with both pulmonary embolism and chronic obstructive pulmonary disease (PE-COPD) with and without deep venous thrombosis (DVT).Aim of the study.To define the prevalence of DVT in COPD with PE and to compare the characteristics of COPD patients who develop PE, with and without DVT. Secondly, we aimed to assess differences in the localization of PE among study groups.Methods.116 patients with pulmonary embolism (PE) were enrolled in a retrospective study. Clinical data as well as echocardiographic and lower limb ultrasonography records were collected for all subjects. Subjects were divided into two groups according to the presence of COPD: Group 1, 54 patients with diagnosis of PE without COPD and Group 2, 66 patients diagnosed of PE with COPD. Then, individuals of Group 2 were subdivided in two subgroups according to the presence (n=21) or absence (n=45) of DVT.Results.33% of patients with COPD and PE showed DVT. These subjects had higher PaCO2 and ejection fraction (p<0.05 for all) and higher percentage of chronic renal failure and diabetes mellitus compared to those without DVT (p<0.05 for all). Moreover, in COPD-PE patients with DVT, the most frequent localization was proximal (54% of total), whereas COPD-PE patients without DVT showed a more frequent segmental localization (60% of total). No difference was found in clinical presentation and blood chemistry tests.Conclusions.DVT was non common in PE-COPD patients. Chronic renal failure, and type 2 diabetes mellitus are more frequent in PE-COPD patients with DVT, that showed a higher frequency of proximal localization, thereby indicating a greater risk of more severe clinical implications. Conversely, PE- COPD subjects without DVT showed a more frequent segmental localization and were less hypercapnic. PE should be taken into account in COPD with worsening of respiratory symptoms, also in absence of DVT. (www.actabiomedica.it).

Pulmonary Arterial Thrombosis in a Murine Model of Blunt Thoracic Trauma.

Pulmonary thromboembolic events cause significant morbidity and mortality after severe trauma. Clinically, these lesions are believed to be emboli arising secondary to deep venous thrombosis (DVT) in the lower extremities. Recently, this notion has been challenged by clinical studies, showing that pulmonary clots arise after trauma in the absence of DVT. This suggests that pulmonary blood clots arise in situ via de novo thrombosis. In the present study, we characterize a murine weight-drop model of lateral blunt thoracic trauma. Our model demonstrates severe unilateral lung contusion injury with low (10%) mortality in the absence of extrapulmonary injury, after impact with a 50-g weight dropped from 45 cm height (657 J/m). At 24 h after injury, immunofluorescence and histological evidence revealed early pulmonary arterial thrombosis in the form of eccentric accumulation of fibrin and CD41 positive eosinophilic proteinaceous material, on both coup and contrecoup lung lobes of injured mice, indicating early thrombotic events both within and outside of the area of primary lung injury. Our model is ideal in that lateral impact enables greater impact energy to be applied to achieve significant lung contusion without significant mortality or extrapulmonary injury, and the model has additional translational value in creating thrombosis analogous to pulmonary embolism observed clinically after blunt thoracic trauma. To our knowledge, this is the first demonstration of de novo pulmonary thrombosis in a clinically translational model of blunt thoracic trauma, and supports challenges to current assumptions about the origin of pulmonary blood clots in the wake of severe traumatic injury.

Differentiation of deep venous thrombosis from femoral vein mixing artifact on routine abdominopelvic CT.

The objective of this study is to assess the performance of qualitative and quantitative imaging features for the differentiation of deep venous thrombosis (DVT) from mixing artifact on routine portal venous phase abdominopelvic CT. This retrospective study included 40 adult patients with a femoral vein filling defect on portal venous phase CT and a Duplex ultrasound (n = 36) or catheter venogram (n = 4) to confirm presence or absence of DVT. Two radiologists (R1, R2) assessed the femoral veins for various qualitative and quantitative features. 60% of patients were confirmed to have DVT and 40% had mixing artifact. Features with significantly greater frequency in DVT than mixing artifact (all p ≤ 0.006) were central location (R1 90% vs. 28%; R2 96% vs. 31%), sharp margin (R1 83% vs. 28%; R2 96% vs. 31%), venous expansion (R1 48% vs. 6%, R2 56% vs. 6%), and venous wall enhancement (R1 62% vs. 0%; R2 48% vs. 0%). DVT exhibited significantly lower mean attenuation than mixing artifact (R1 42.1 ± 20.2 vs. 57.1 ± 23.6 HU; R2 43.6 ± 19.4 vs. 58.8 ± 23.4 HU, p ≤ 0.031) and a significantly larger difference in vein diameter compared to the contralateral vein (R1 0.4 ± 0.4 vs. 0.1 ± 0.2 cm; R2 0.3 ± 0.4 vs. 0.0 ± 0.1 cm, p ≤ 0.026). At multivariable analysis, central location and sharp margin were significant independent predictors of DVT for both readers (p ≤ 0.013). Awareness of these qualitative and quantitative imaging features may improve radiologists' confidence for differentiating femoral vein DVT and mixing artifact on routine portal venous phase CT. However, given overlap with mixing artifact, larger studies remain warranted.

Efficacy of prophylactic inferior vena caval filters in prevention of pulmonary embolism in the absence of deep venous thrombosis.

There is an increasing use of inferior vena caval filters (IVCFs) as prophylactic activity in the absence of a deep venous thrombosis (DVT) to prevent pulmonary embolism (PE) in high-risk patients. These devices are effective in preventing PE in the presence of lower extremity DVT, when anticoagulation is contraindicated or has failed. An electronic databases search of MEDLINE, PubMed, The Cochrane Library, and Google Scholar for relevant articles listed between January 2000 and December 2014 was performed. The review was confined to patients without a history of previous venous thromboembolism and no evidence of changes on venous duplex imaging suggestive of previous DVT. At present, the use of prophylactic IVCF is predominantly in the trauma, orthopedic, and bariatric surgical populations. Currently, no class I studies exist to support insertion of an IVCF in a patient without anestablished DVT or PE. However, there is a body of classIIand class III evidence that would support the use of IVCFs incertain "high-risk" patients who do not have a documented DVT or the occurrence of a PE. Widespread use of prophylactic IVCFs isnot supported by evidence and should be discouraged.

Suspected Pulmonary Thromboembolism and Deep Venous Thrombosis: A Comprehensive 64-slice Multidetector Computed Tomography Diagnosis in Gynecologic Patients.

Suspected Pulmonary Thromboembolism and Deep Venous Thrombosis: A Comprehensive 64-slice Multidetector Computed Tomography Diagnosis in Gynecologic Patients.

Association of Deep Venous Thrombosis with Calf Vein Diameter in Acute Hemorrhagic Stroke

We investigated the association between the development of deep venous thrombosis (DVT) and calf vein diameter in patients with acute hemorrhagic stroke. We measured the maximum diameter of paralytic side posttibial veins (PTVs) and peroneal veins (PVs) in 49 patients with intracerebral hemorrhage on admission and at 2 weeks after stroke onset by ultrasonography. We also examined for the presence or absence of DVT, and then analyzed the association of DVT with the maximum vein diameter. At 2 weeks after stroke, DVTs were detected in PTVs in 7 patients and in PVs in 6 patients. The maximum calf vein diameters at 2 weeks were significantly greater in patients with DVT compared with those without DVT (PTV, P = .033; PV, P = .015). Although calf vein diameter at admission did not influence the future incidence of DVT in patients with intracerebral hemorrhage, the presence of DVT was associated with calf vein dilatation.

Short-term outcome analysis of radiofrequency ablation using ClosurePlus vs ClosureFast catheters in the treatment of incompetent great saphenous vein

Radiofrequency ablation (RFA) is a widely accepted alternative to high ligation with proximal stripping of the great saphenous vein (GSV) in the treatment of lower extremity venous insufficiency. This study compared short-term outcomes of two generations of (VNUS Closure) RFA catheters, ClosurePlus (CP) and ClosureFast (CF). From February 2005 to April 2009, a total of 667 consecutive office-based RFA procedures were performed in our institution. CP catheters were used in the initial 312 lower extremity cases and CF catheters in the 355 cases that followed. The technique used for both catheters were as per the manufacturer's recommendations. Postoperative duplex scans were completed to document the following endpoints: GSV obliteration; incidence of deep venous thrombosis (DVT); superficial venous thrombosis (SVT); and presence of loose or floating thrombus proximal to the treated GSV segment. Of the 667 cases, 98% had available duplex scan studies within 1 week from completion of the procedure. Complete obliteration of the GSV on duplex scan studies was noted in 98% of 343 cases using the CF catheter and 88% of 312 cases using the CP catheter (P < .001). No case of DVT was detected in those treated with the CF catheter, whereas DVT occurred in 3.5% of cases treated with the CP catheter (P < .001). Incidence of SVT was 10% and 15%, respectively, for CF and CP (P < .08). Loose thrombus proximal to the GSV was identified in 7% of cases using CF and 6% of cases using CP (P = .80). No embolic episodes were observed clinically. CF catheters are superior to CP catheters in terms of GSV obliteration and nonincidence of postoperative DVT. The absence of DVT may likely be due to the commencement of ablation at 2 cm from the GSV-common femoral vein junction.

Idiopathic deep venous thrombosis and arterial endothelial dysfunction in the elderly

Arterial and venous thrombosis have always been regarded as different pathologies and epidemiological studies have examined the association between venous thrombosis and indicators of atherosclerosis and/or arterial thromboembolic events. We measured the flow-mediated dilation (FMD), a well-known marker of arterial endothelial dysfunction, in young-middle-aged and old-aged patients with and without unprovoked deep venous thrombosis (DVT). The aim of this study was to investigate whether DVT was a significant predictor for impaired FMD, considering all the patients and young-middle-aged (age < 65 years) and old-aged (age ≥ 65 years) patients separately. FMD was measured in the brachial artery on a population of 120 subjects with the same atherosclerosis risk factors, 68 male and 52 female, 70 young-middle-aged subjects (mean age ± SD 49.5 ± 10.5 years) and 50 old-aged subjects (76.2 ± 7.7 years). Patients with DVT showed a significant decrease of FMD compared to patients without DVT (6.8 ± 5.5% vs. 10.9 ± 3.5%, p < 0.001). Moreover, old-aged patients showed a significant decrease of FMD compared to the young-middle-aged subjects (7.4 ± 4.1% vs. 9.8 ± 5.3%, p = 0.005). In the whole study population, DVT was strongly associated with FMD (risk factors adjusted β = -4.14, p < 0.001). A significant interaction between age and the presence of DVT on predicting FMD was found (p = 0.003) suggesting a differential behavior of DVT as predictor of FMD. In young-middle-aged group, multivariate model confirmed that DVT was the most significant predictor of continuous FMD (β = -6.06, p < 0.001). On the contrary, DVT was no more a predictor of FMD in the old age group (β = -0.73, p = 0.556). Furthermore, old-aged patients without DVT showed a statistically significant decrease of FMD compared to the young-middle-aged subjects without DVT (8.2 ± 2.1% vs. 12.6 ± 2.7%, p<0.001) and old-aged patients with DVT showed a not statistically significant decrease of the FMD compared to the young-middle-aged patients with DVT (6.7 ± 5.3% vs. 6.8 ± 5.7%, p = 0.932). In conclusion, young-middle-aged patients with spontaneous DVT show an impaired FMD, whereas this impairment in old-aged subjects is evident independently from the presence or absence of DVT. Aging per se may be associated with physiologic abnormalities in the systemic arteries and with endothelial dysfunction.

Pitfalls in the Diagnosis and Treatment of Subsegmental Pulmonary Emboli Detected by CTPA

PURPOSE: CTPA has significantly increased the detection of subsegmental pulmonary emboli (SSPE). Whether SSPE, in the absence of deep venous thrombosis (DVT), should be treated is controversial. We investigated the problems associated with therapeutic anticoagulation for officially reported SSPE in the community hospital setting.

Trends in vena caval interruption

This study examined the national use of vena cava filters (VCFs) from 1998 to 2005. Methods for complex surveys were used to examine hospital discharge data from the Nationwide Inpatient Sample (NIS) to determine the use of VCFs for the years 1998 to 2005. VCF placement in the absence of deep venous thrombosis (DVT) or pulmonary embolus (PE) was categorized as prophylactic. During the study period, the estimated rate of hospitalizations per year with a diagnosis of DVT (odds ratio [OR], 1.025; 95% confidence interval [CI], 1.019-1.032; P < .01) or PE (OR, 1.076; 95% CI, 1.069-1.083; P < .01) rose significantly. The estimated weighted frequency of VCF placement increased from 52,860 procedures in 1998 to 104,114 procedures in 2005 (0.15% and 0.27% of all discharges, respectively), representing an 80% increase. VCF placement significantly increased during hospitalizations with any diagnosis of DVT or PE, or both, and no DVT or PE (P < .01 for each). Logistic regression models revealed that the rate of prophylactic VCF placement increased at a significantly higher rate than VCF placement associated with DVT or PE (157% vs 42%; P < .01), after adjusting for age, gender, and hospital characteristics. Prophylactic VCF placement in the setting of morbid obesity (P < .01) and head injury (P = .03) rose significantly over time. From 1998 to 2005, the estimated rates of prophylactic VCF placement increased at a significantly higher rate than VCF placement in the setting of DVT or PE. Significant increases in the use of prophylactic VCFs were seen in the setting of morbid obesity and head injury.

Predicting Deep Venous Thrombosis in Pregnancy: Out in “LEFt” Field?

In the nonpregnant general population, deep venous thrombosis (DVT) can be excluded at the initial presentation not only by clinical assessment and review of risk factors, but also by the clinician's assessment of probability using subjective criteria or prediction rules. Because of the absence of a validated prediction rule for diagnosing DVT during pregnancy, diagnosis in pregnant patients depends largely on the use of compression ultrasonography, the diagnostic reference standard that establishes the presence or absence of DVT. The aim of this cross-sectional study was to investigate the predictive accuracy of clinicians' subjective assessment of the probability of DVT in women with suspected DVT and to identify useful objective prediction variables. The participants were 194 unselected pregnant women with suspected first DVT. Potential study patients were identified by clinicians during the initial examination when the clinical assessment was consistent with DVT, and led to consultation with thrombosis experts who obtained informed consent for participation in the study. Before compression ultrasonography testing, the experts examined each study patient and categorized their pretest probability of DVT based on subjective criteria as low, moderate, or high. The sensitivity, specificity, negative predictive value, and likelihood ratios of the clinicians' subjective pretest probability were calculated. Patients defined as DVT positive had abnormal diagnostic compression ultrasonography results at the initial presentation or during serial testing, or had symptomatic DVT or pulmonary embolism on follow-up. Patients with negative compression ultrasonography at presentation and no venous thromboembolism on follow-up were defined as DVT negative. DVT was diagnosed in 17 women (8.8%). The prevalence of DVT in patients with low pretest probability (two-third of patients) was 1.5% (2/131), with a 95% confidence interval of 0.4% to 5.4% (P < 0.001). The prevalence among those with moderate or high pretest probability was considerably higher, 24.6% (15/61), with a 95% confidence interval of 15.5% to 36.7% (P < 0.001). Multivariate analysis identified 3 independent variables that were highly predictive of DVT in pregnant women: left leg symptoms, difference in calf circumference of 2 cm or more, and presentation during the first trimester of pregnancy. DVT was unlikely in the absence of all 3 variables, and its probability increased substantially if 1 or more was present. These findings demonstrate that probability of DVT in pregnant women with suspected DVT may be assessed with use of 3 easily determined objective variables. The data show that DVT is very unlikely with a very low pretest probability.

A Red Blood Cell Agglutination d-Dimer Test to Exclude Deep Venous Thrombosis in Pregnancy

D-Dimer testing is often used with compression ultrasonography for the diagnosis of deep venous thrombosis (DVT) in nonpregnant patients. The D-dimer test is highly sensitive, and a negative result can obviate the need for further testing for DVT. This test has not been studied for DVT diagnosis in pregnancy because its specificity was deemed too poor. To determine the sensitivity and specificity and assess the utility of the SimpliRED assay (Agen Biomedical, Brisbane, Australia) for the diagnosis of DVT in pregnant women. Prospective cohort study. 5 tertiary university-affiliated Canadian hospitals providing care to obstetric patients. 149 consecutive pregnant women with suspected DVT who presented to 1 of the participating centers over 5 years. Participating women were tested with compression leg ultrasonography (single or serially on days 0, 3, and 7) and received 3 months' clinical follow-up for the presence or absence of DVT. Whole blood was tested with the SimpliRED assay at initial presentation, and results were correlated with ultrasonography and clinical findings for the presence or absence of DVT. The sensitivity, specificity, and negative predictive value of the SimpliRED assay were calculated, along with the prevalence of false-positive SimpliRED assay results (with 95% CIs). The prevalence of DVT in the cohort was 8.7% (95% CI, 5.2% to 14.4%). The sensitivity of the SimpliRED assay was 100% (CI, 77% to 100% [13 of 13 patients]), the specificity was 60% (CI, 52% to 68% [81 of 135]), and the negative predictive value was 100% (CI, 95% to 100% [81 of 81]). The SimpliRED assay was positive in 0% (CI, 0% to 60%), 24% (CI, 14% to 37%), and 51% (CI, 40% to 61%) of women in the first, second, and third trimesters, respectively, among pregnant patients in whom DVT was not diagnosed. The prevalence of DVT in the cohort was low, resulting in wide CIs. The clinician's previous impression was used to determine pretest probability in the absence of a validated clinical prediction rule for pregnant women. The SimpliRED assay may be useful in pregnancy because a normal result excludes DVT and occurs frequently enough to be clinically helpful.

The Wells rule was not useful in ruling out deep venous thrombosis in a primary care setting

Oudega R, Hoes AW, Moons KG. The Wells rule does not adequately rule out deep venous thrombosis in primary care patients. Ann Intern Med 2005;143:100–7. [OpenUrl][1][CrossRef][2][PubMed][3][Web of Science][4] Q In...

Deep Venous Thrombosis Prophylaxis: Better Living Through Chemistry—In Opposition

The best prophylactic regimens for thromboembolic disease continue to be debated despite years of investigation. The surgeon must balance the clinical risks and benefits. A decision depends on accurate data and our ability to balance the risks of fatal pulmonary embolism (PE) to the risk of bleeding. The current risk for fatal PE is 0.1% with most current prophylactic regimes. The risk of perioperative bleeding increases 1.8% to 5.2% with low molecular weight heparins or warfarin and generally is dose dependent. Most of the current prophylactic recommendations are based on the presence or absence of deep venous thrombosis (DVT). However, the correlation between the presence of a DVT and the risk of PE is low and inconsistent. Therefore, DVT may not be an accurate surrogate marker for the patient at risk after total joint surgery. Our experience with 2800 consecutive total knee arthroplasty patients, using aspirin as our principle agent, shows a fatal PE risk of 0.1% and a low risk of bleeding. Therefore, our current recommendation is aspirin.

Color-Doppler sonography in chronic venous insufficiency: What the radiologist should know

Chronic venous insufficiency (CVI) is a pathologic condition caused by valvular incompetence, with or without associated venous outflow obstruction, which may affect both the superficial and the deep venous system, causing venous hypertension and stasis. The most common form of CVI is primary varicose veins due to the insufficiency of the saphenous system. Color-Doppler sonography (CDS) is actually the main diagnostic technique of imaging for CVI. In this article, we describe the anatomy, the technique, and the information necessary to the radiologist to perform CDS in chronic venous insufficiency. The knowledge of the venous anatomy is the cornerstone for an adequate sonographic examination. The venous network in the lower extremities is divided into three systems: superficial, deep, and perforating veins. Deep veins are "comitantes" to the corresponding arteries and run under the muscular fascia. Superficial veins course into the subcutaneous fat, superficially to the deep muscular fascia; the main superficial veins are the greater and lesser saphenous and their tributaries. Connection between the saphenous veins are defined as communicating veins. Superficial and deep veins are connected by perforating veins, with flow directed, under normal circumstances, from the superficial to the deep system. The main perforating are the Hunter in the mid thigh, the Dodd in the lower thigh, the Boyd in the upper calf, and the Cockett's in the middle and lower calf. Sonographic examination must be performed in the upright and supine position. Compression sonography and color and PW Doppler are systematically employed to assess the absence of deep venous thrombosis. Femoro-popliteal veins are evaluated with color and PW Doppler for valvular insufficiency with reflux by performing Valsalva maneuver and calf compression. The sapheno-femoral and sapheno-popliteal junctions are examined to identify type of junction, continence, accessory saphenous, and incompetent collaterals. Perforating veins are usually identified at the medial aspect of the thigh and at the medial, lateral, and posterior aspects of the leg. Outward flow (lasting more than 500 ms) in the perforating veins should be considered a sign of their incompetence. Several surgical and interventional procedures are now available for the treatment of the CVI, as follows: vein ligation and stripping, stab avulsion, endoluminal occlusion of the saphenous trunks, subfascial endoscopic perforator surgery, and valvuloplasty.

Suspected Acute Deep Vein Thrombosis of the Lower Limb in Outpatients: Considerations for Optimal Diagnostic Approach

The objective of this study was to review our diagnostic approach using color duplex scanning (CDS) in the management of symptomatic outpatients with suspected lower limb deep venous thrombosis (DVT). CDS was carried out in 315 consecutive outpatients with unilateral symptoms consistent with DVT. Both limbs were assessed in 205 patients. Other pathology was routinely sought when the symptomatic limb was free of thrombosis. Acute DVT was present in 25% (76/315) of the symptomatic limbs, and in only 8% it was confined to calf veins. Other pathology was detected in 90 limbs (28%). Swelling with or without pain was associated with DVT in 44% and 10%, respectively. The time elapsed between the onset of symptoms and CDS was 3 days (range 1-6 days). DVT in the contralateral asymptomatic limb was present in 5 (9%) of the 56 patients with DVT in the symptomatic limb. In the absence of DVT in the symptomatic limb, the contralateral asymptomatic limb was free of thrombosis. Clinical diagnosis of DVT in outpatients was unreliable. CDS revealed that only one-fourth of the symptomatic limbs had DVT, and other pathology mimicking DVT was present in 28%. CDS is a useful tool that offers a prompt, efficient diagnosis. Investigation of the contralateral asymptomatic limb seems to be necessary only when DVT is found in the symptomatic limb.

Long-term follow-up of Greenfield inferior vena cava filter placement in children

Objective: The long-term results of Greenfield inferior vena cava (IVC) filter placement have been well documented in adults; however, similar data do not exist for pediatric patients. The potential for growth and the increased life expectancy in younger patients may contribute to a difference in the natural history of filters placed in children. The objective of this study was to evaluate the long-term outcome of pediatric patients with IVC filters. Methods: At the University of Massachusetts Memorial Medical Center, medical records and radiographs of patients 18 years old or younger at the time of IVC filter placement were reviewed. Follow-up data were obtained by interview, physical examination, and venous duplex ultrasound scanning. Results: A total of 15 IVC filters were placed in children 18 years old or younger between 1983 and 1999. In 10 patients the indications for IVC filter placement were lower-extremity deep venous thrombosis (DVT) and/or pulmonary embolism. In five patients, prophylactic filters were placed in the absence of DVT because of a high risk for the development of pulmonary embolism. Surgical exposure of the right internal jugular vein was used to place the first eight filters. The remainder were inserted percutaneously through the right internal jugular vein or the right common femoral vein. There were no complications or mortality related to filter insertion. Follow-up of the surviving 14 patients ranged from 19 months to 16 years. During long-term follow-up, no patient had a pulmonary embolus. Of the nine patients who had lower-extremity DVT, three developed mild common femoral venous reflux documented by duplex scan. Of the five patients who had prophylactic filters, four had no symptoms or duplex evidence of reflux. The other patient, who was paraplegic, had bilateral leg edema but no venous varicosities and no reflux on duplex scan 11 years after filter placement. No patient in either group had chronic venous obstruction. Conclusion: In long-term follow-up there were no instances of pulmonary embolism, IVC thrombosis, significant postphlebitic symptoms, or significant filter migration among 14 pediatric patients with Greenfield IVC filters. This suggests a safety profile and efficacy similar to that seen in adults. (J Vasc Surg 2001;34:820-5.)