The anatomy of deep venous thrombosis of the lower extremity

Prevalence and risk factors for proximal deep vein thrombosis at admission in patients with traumatic fractures: a multicenter retrospective study

Objective

This study aimed to determine the associated risk factors for proximal deep vein thrombosis (DVT) in patients with lower extremity and pelvic-acetabular fractures.

Methods

The medical records of 4,056 patients with lower extremity and pelvic-acetabular fractures were retrospectively reviewed. The patients were classified into proximal or non-proximal DVT groups. Logistic regression models were used to determine the independent risk variables for proximal DVT. The predictive value of the related risk factors was further analyzed using receiver operating characteristic curves.

Results

The prevalence of proximal DVT was 3.16%. Sex, body mass index (BMI), fracture site, injury mechanism, diabetes, coronary heart disease (CHD), injury-to-admission interval, hematocrit, platelet counts, and D-dimer levels differed significantly between the two groups. BMI ≥ 24.0 kg/m2, femoral shaft fractures, high-energy injury, diabetes, injury-to-admission interval >24 h were independent risk factors for proximal DVT. CHD decreased the risk of proximal DVT. The platelet and D-dimer had high negative predictive value for predicting proximal DVT formation, with cut-off values of 174 × 109/L and 2.18 mg/L, respectively.

Conclusion

BMI ≥ 24.0 kg/m2, femoral shaft fractures, high-energy injury, diabetes, injury-to-admission interval >24 h were independent risk factors for proximal DVT in patients with lower extremity and pelvic-acetabular fractures. Platelet count and D-dimer level were effective indicators for excluding proximal DVT occurrence. CHD decreased the risk of proximal DVT.

The correlation between the CT angiographic pulmonary artery obstructive index and clinical data in patients with acute pulmonary thromboembolism

PURPOSE

The potentially fatal consequences of pulmonary embolism emphasize the need for more effective diagnostic methods. The Qanadli obstruction index has been described as a convenient tool for risk stratification to determine and quantify the degree of obstruction. This study aimed to assess the correlations between the Qanadli index with clinical and paraclinical findings (D-dimer, troponin, and echocardiographic findings) in patients with pulmonary embolism.

MATERIALS AND METHODS

A total of 102 patients with pulmonary embolism underwent echocardiography and CT pulmonary angiography at a single tertiary referral center between 2019 and 2020. The clinical and paraclinical findings, pulmonary arterial obstruction index, atrial measurements, right and left ventricle size and function, tricuspid annular plane systolic excursion, pulmonary artery pressure, and pulmonary hypertension (PH) were analyzed. Vital signs were recorded and assessed. The Qanadli index score was measured, and graded risk stratification was measured based on the quantified index score.

RESULTS

The total mean Qanadli index was 28.75 ± 23.75, and there was no significant relationship between the Qanadli index and gender. Patients' most common clinical findings were exertional dyspnea (84.3%; n = 86) and chest pain (71.7%; n = 73). There were significant correlations between the Qanadli index and pulse rate (PR), troponin, D-dimer levels, and PH. Four patients died during the study, including one from a cardiac condition and three with non-cardiac conditions.

CONCLUSIONS

It is possible to determine the severity, prognosis, and appropriate treatment by the Qanadli index based on strong correlations with PR, troponin, D-dimer levels, and PH.

Pulmonary artery embolism: comprehensive transcriptomic analysis in understanding the pathogenic mechanisms of the disease

BACKGROUND

Pulmonary embolism (PE) is a severe disease that usually originates from deep vein thrombosis (DVT) of the lower extremities. This study set out to investigate the changes in the transcriptome of the pulmonary artery (PA) in the course of the PE in the porcine model.

METHODS

The study was performed on 11 male pigs: a thrombus was formed in each right femoral vein in six animals, and then was released to induce PE, the remaining five animals served as a control group. In the experimental animals total RNA was isolated from the PA where the blood clot lodged, and in the control group, from the corresponding PA segments. High-throughput RNA sequencing was used to analyse the global changes in the transcriptome of PA with induced PE (PA-E).

RESULTS

Applied multistep bioinformatics revealed 473 differentially expressed genes (DEGs): 198 upregulated and 275 downregulated. Functional Gene Ontology annotated 347 DEGs into 27 biological processes, 324 to the 11 cellular components and 346 to the 2 molecular functions categories. In the signaling pathway analysis, KEGG 'protein processing in endoplasmic reticulum' was identified for the mRNAs modulated during PE. The same KEGG pathway was also exposed by 8 differentially alternative splicing genes. Within single nucleotide variants, the 61 allele-specific expression variants were localised in the vicinity of the genes that belong to the cellular components of the 'endoplasmic reticulum'. The discovered allele-specific genes were also classified as signatures of the cardiovascular system.

CONCLUSIONS

The findings of this research provide the first thorough investigation of the changes in the gene expression profile of PA affected by an embolus. Evidence from this study suggests that the disturbed homeostasis in the biosynthesis of proteins in the endoplasmic reticulum plays a major role in the pathogenesis of PE.

Venous thrombosis: a mimic of musculoskeletal injury on MR imaging

Clinical signs and symptoms of venous thrombosis and musculoskeletal pathologies frequently overlap. Sometimes, patients with venous thrombosis undergo MR examinations under an equivocal suspicion of muscle, tendon or articular injury. A low pretest clinical suspicion and lack of familiarity with the conventional MR imaging signs of venous thrombosis may result in failure to diagnose venous thrombosis, delaying treatment and raising morbimortality. In MR imaging, thrombosis presents as venous ectasia with intraluminal heterogeneous content. Small vein thrombosis is often identified as having a branching aspect. Perivenous edema and inflammatory soft tissue changes may be the most prominent findings. The purpose of this paper is to illustrate MR findings of venous thrombosis in patients who underwent MR examinations due to suspected musculoskeletal pathologies. Cases of venous thrombosis in different sites of the body diagnosed through MR are presented.

[Arm Swelling with a Camouflaged Cause]

Arm Swelling with a Camouflaged Cause Abstract. We report on a 72-year-old patient who presented to the emergency department due to a proximal multiple-fragment humeral fracture on the left. Despite correct therapeutic approaches, there was no improvement in the left arm swelling. Further investigations showed a provoked arm vein thrombosis on the left with a post-humeral fracture on the left. After therapeutic anticoagulation, the swelling regressed immediately, but with persistent lymphedema of the left hand.

Venous Anatomy and Collateral Pathways of the Pelvis: An Angiographic Review

The pelvic venous system is complex, with the potential for numerous pathways of collateralization. Owing to stenosis or occlusion, both thrombotic and nonthrombotic entities in the pelvis may necessitate alternate routes of venous return. Although the pelvic venous anatomy and collateral pathways may demonstrate structural variability, a number of predictable paths often can be demonstrated on the basis of the given disease and the level of obstruction. Several general categories of collateral pathways have been described. These pathway categories include the deep pathway, which is composed of the lumbar and sacral veins and vertebral venous plexuses; the superficial pathway, which is composed of the circumflex and epigastric vessels; various iliofemoral collateral pathways; the intermediate pathway, which is composed of the gonadal veins and the ovarian and uterine plexuses; and portosystemic pathways. The pelvic venous anatomy has been described in detail in cadaveric and anatomic studies, with the aforementioned collateral pathways depicted on CT and MR images in several imaging studies. A comprehensive review of the native pelvic venous anatomy and collateralized pelvic venous anatomy based on angiographic features has yet to be provided. Knowledge of the diseases involving a number of specific pelvic veins is of clinical importance to interventional and diagnostic radiologists and surgeons. The ability to accurately identify common collateral patterns by using multiple imaging modalities, with accurate anatomic descriptions, may assist in delineating underlying obstructive hemodynamics and diagnosing specific occlusive disease entities. ^©RSNA, 2022.

Comparison of examination techniques of anterior and posterior compartments of the leg for the diagnosis of deep vein thrombosis: A new examination technique

Objectives

Several examination techniques have been described for the diagnosis of leg deep vein thrombosis. These previously described examination techniques aim to detect muscle pain that occurs secondary to increased pressure in the posterior compartment of the leg. However, to the best of our knowledge no studies investigated the frequency of muscle pain on the anterior compartment in patients with leg deep vein thrombosis the objective of this study is to investigate the prevalence of muscle pain in the anterior compartment.

Methods

The patients who were diagnosed with acute deep vein thrombosis were included in this prospective cross-sectional study. Each patient was examined using the techniques that determine the pain on the posterior compartment as well as using the technique we described to detect muscle pain on the anterior compartment.

Results

Two hunderd forty three patients were enrolled in the study. Among those, both distal and proximal deep vein thrombosis was present in 128 (52.7%) patients. 75% of them had muscle pain in the anterior compartment.

Conclusion

The results suggested that examination of muscle pain in anterior compartment of leg in patients with both proximal and distal deep vein thrombosis can be used as an additional physical examination techniques for early diagnosis.

Patients with right lower extremity deep vein thrombosis have a higher risk of symptomatic pulmonary embolism: a retrospective study of 1585 patients

OBJECTIVE

To determine the risk for pulmonary embolism (PE) and explore the relationship between the site of thrombosis and PE in patients with acute lower extremity deep vein thrombosis (DVT).

METHODS

1585 hospitalized patients first diagnosed with acute lower extremity DVT were investigated retrospectively. The patients were divided into two groups: the non-PE group (Group 1) and the PE group (Group 2). Then, Group 2 was divided into two subgroups: asymptomatic pulmonary embolism (asPE, Group 2a) and symptomatic pulmonary embolism (sPE, Group 2b). Kaplan-Meier curves and logistic regression analysis were used to explore the relevant risk factors for PE.

RESULTS

Among 1585 patients, 458 patients suffered from PE, accounting for 28.9%. 102 (22.3%) of them had the typical clinical manifestations of PE and were defined as sPE, and the remaining 356 (77.7%) patients were classified as asPE. Patients with proximal lower extremity DVT were significantly more predominant in the PE group than in the non-PE group (92.8% vs. 86.2%, p<0.001). Moreover, in Group 2, patients with typical PE manifestations showed a higher proportion of patients with right lower extremity DVT than left lower extremity DVT (26.7% vs. 17.7%, P=0.035), and bilateral lower extremity DVT than unilateral DVT (44.1% vs. 20.5%, p<0.001). By multivariate analysis, alcohol consumption (OR, 1.824; 95% CI, 1.194-2.787; p=0.005), heart failure (OR, 2.345; 95% CI, 1.560-3.526; p<0.001), proximal DVT (OR, 2.096; 95% CI,1.407-3.123; p<0.001) were independent risk factors for PE.

CONCLUSION

Patients with proximal acute lower extremity DVT were more likely to suffer from PE than those with distal DVT. Patients with right acute lower extremity DVT had a higher risk of sPE than patients with left acute lower extremity DVT. Alcohol consumption and heart failure were associated with the occurrence of PE in patients with acute lower extremity DVT.

Incremental value of compression ultrasound sonography in the emergency department

The quick evaluation of venous thromboembolism is a key point of modern medicine since the delayed diagnosis is associated with a worse prognosis. Venous ultrasound (VU) is a sensitive and rapidly performed test in cases of suspected deep venous thrombosis. Various protocols have been proposed for its execution, such as the study of the whole deep venous circulation of the lower limb or the analysis of the femoral-popliteal area. The aim is to detect a vessel thrombus and the most sensitive element is the non-compressibility with the probe. Initially, the thrombus is hypoechogenic and adherent to the vessel; later, it tends to organize and recanalize. Usually, in the early stages, the risk of embolism is higher. The role of studying the iliac axis and calf veins is still uncertain. VU is not useful for assessing response to anticoagulation therapy and it is unclear whether the persistence of thrombotic abnormalities can guide on a possible prolongation of therapy.

Association between Laterality and Location of Deep Vein Thrombosis of Lower Extremity and Pulmonary Embolism

Purpose

The aim of this study was to investigate the relationship between the anatomical location of thrombi in the lower extremities and the development of pulmonary embolism (PE).

Methods

Materials and We collected and analyzed the data of patients diagnosed with deep vein thrombosis (DVT) of the lower extremities between 2006 and 2015, and included those whose computed tomography (CT) data were available for PE identification. We evaluated the relationship between the laterality and the proximal/distal location of the thrombi in lower extremites and the location of PE.

Results

CT images were available for 388/452 patients with DVT. After excluding 32 cases with bilateral involvement, 356 cases were included for analysis in this study. The ratio of DVT in the left:right leg was 232:124. PEs developed in 121 (52.2%) patients with left-sided DVT and in 78 (62.9%) with right-sided DVT (P=0.052). PEs in the main pulmonary arteries developed in 36 (15.5%) patients with left leg DVT and in 30 (24.2%) with right leg DVT (P=0.045). The most frequent site of thrombosis associated with the development of PE was the left iliac vein (59/199, 29.6%). According to the anatomical segment of the leg affected by DVT, patients with DVT in the right femoral vein (50/71, 70.4%; P=0.016) had the highest rate of occurrence of PE.

Conclusion

PE develops more frequently in patients with right-sided DVT than in those with left-sided DVT. Therefore, careful observation for the possible development of PE is recommended in cases with right-sided DVT of the lower extremity.

The anatomic distribution and pulmonary embolism complications of hospital-acquired lower extremity deep venous thrombosis

OBJECTIVE

The anatomic distribution of lower extremity deep venous thrombosis (LEDVT) plays an important role in its prevention and treatment. This study aimed to evaluate the anatomic distribution of hospital-acquired LEDVT (HA-LEDVT) and its probable role in the occurrence of pulmonary embolism (PE).

METHODS

We retrospectively analyzed the demographic data, ultrasound results, and PE-related findings of inpatients with HA-LEDVT in 28 clinical departments at Peking University People's Hospital between January 1, 2007, and December 31, 2018.

RESULTS

This study included 1431 HA-LEDVT events: 35.8%, 31%, and 33.3% were left, right, and bilateral LEDVT. Isolated distal, proximal, and blended DVT were detected in 83.4%, 7.3%, and 9.3% of the patients, respectively. The distribution of HA-LEDVT in the left and right lower extremities were not significantly different except in patients aged ≥40 years (left: 2.07 vs right: 1.88 per 1000 extremities, P = .04). For anatomic types of HA-LEDVT, isolated distal HA-LEDVT was 5.02 times more prevalent than proximal HA-LEDVT (1.24 vs 0.26 per 1000 extremities, P ＜ .01). The involvement rates of specific deep veins by HA-LEDVT were highest in the muscular calf vein (87.5%) followed by the popliteal vein (10.1%), superficial femoral vein (9.3%), and common femoral vein (9.2%). HA-LEDVT involving multiple vein segments simultaneously occurred in 338 extremities. HA-LEDVT involving the muscular calf vein and at least one of three connected axial veins of the muscular calf vein occurred most frequently. Eighty-eight patients with HA-LEDVT (6.15%) had PE. The frequency of PE among patients with proximal and distal DVT (7.89% vs 6.23% P = .275) was not significantly different. The incidence of PE was highest in patients with bilateral proximal DVT (15.4%) and lowest in patients with a single right distal DVT (4.5%). PE occurred in 6% of muscular calf vein HA-LEDVT. In isolated muscular calf vein DVT cases, PE were more likely to occur in cases with a ＞6.05-mm-diameter thrombus than in those with a ＜6.05-mm-diameter thrombus (10.3% vs 4.2%, P ＜ .0001).

CONCLUSIONS

HA-LEDVT is characterized by a significantly high percentage of DVT in the muscular calf vein. Muscular calf vein thrombosis may be the primary origin of lower extremity deep vein thrombosis. The diameter of the thrombus in the muscular calf vein may be associated with the occurrence of PE. More prospective studies are needed to more fully determine the natural history of HA-LEDVT and develop prevention and treatment guidelines for HA-LEDVT.

Deep Venous Thrombosis Recurrence and Its Predictors at Selected Tertiary Hospitals in Ethiopia: A Prospective Cohort Study

Deep venous thrombosis (DVT) is a common clinical problem associated with substantial morbidity and mortality. Knowledge of the global burden of DVT recurrence is deficient in Africa, including Ethiopia. The objective of the study was to assess deep venous thrombosis recurrence and its predictors at selected tertiary hospitals in Ethiopia. Prospective cohort study was conducted among hospitalized DVT patients. Data were analyzed using SPSS version 21.0. To identify the independent predictors of DVT-recurrence, multiple stepwise-backward Cox-regression analysis was done. Statistical significance was considered at P value < .05. A total of 129 participants were included (65.1% females) with mean ± SD age of 38.63 ± 17.67 years. About 26.4% of patients developed recurrent venous thromboembolism. Pulmonary embolism accounted for 17.60% of recurrent event. The overall incidence density of DVT recurrence was 2.99 per 1000 person-days. The mean ± SD survival time to DVT recurrence was 42.03 ± 22.371 days. Age ≥ 50 years (adjusted hazard ratio [AHR]: 5.566; 95% CI: 1.587-19.518; P = .007), occasional alcohol consumption (AHR: 2.011; 95% CI: 1.307-6.314; P = .019), surgical history (AHR: 6.218; 95% CI: 1.540-25.104; P = .010), pregnancy (AHR: 2.0911; 95% CI: 1.046-4.179; P = .037), diabetes mellitus (AHR: 8.048; 95% CI: 2.494-25.966; P < .001), unmet activated partial thromboplastin time target after 24 hours of heparin (AHR: 1.129; 95% CI: 0.120-10.600; P = .011), proximal site involvement (AHR: 5.937; 95% CI: 1.300-27.110; P = .022), and previous history of DVT (AHR: 2.48; 95% CI: 1.085-11.20; P = .0002) were independent predictors of DVT recurrence. The DVT recurrence rate was high in the study area, which is even complicated with pulmonary embolism as well as death. Efforts are needed to prevent and reduce the development of DVT recurrence.

Targeted gene expression analysis of human deep veins

OBJECTIVE

Endothelial-derived molecules involved in thrombosis and hemostasis have been investigated mainly in arteries and in experimental animals. The actual presence and integral function of these molecules in the human deep venous system have received less attention. Our aim was to evaluate the expression of certain prothrombotic and antithrombotic genes in the normal human deep veins of the lower extremities.

METHODS

Macroscopically intact and competent valve-containing segments of human deep veins were prospectively collected from patients who had undergone above-knee amputation. Vein samples were separated into four zones: zone 1, postvalve (downstream, proximal) vein wall; zone 2, the valve cusp; zone 3, prevalve (upstream, distal) vein wall; and zone 4, vein wall within the valve cusp (cusp removed). Real-time quantitative polymerase chain reaction for principal genes involved in coagulation, fibrinolysis, and inflammation was performed to quantify messenger RNA. Selected protein gene products were measured by the western blot assay. One additional valve-containing segment underwent mass spectrometry analysis to investigate global differences in the proteome between the study zones.

RESULTS

Seventeen valve-containing vein segments were analyzed. Significant upregulation of antithrombotic (protein C receptor [PROCR], thrombomodulin [THBD], tissue factor pathway inhibitor [TFPI]), prothrombotic (con Willebrand factor [VWF]), and proinflammatory (selectin P [SELP], intercellular adhesion molecule 1 [ICAM1]) genes was found in the valve cusp compared with the vein wall (P < .05). PROCR and THBD demonstrated the highest level of upregulation in the valve cusp. PROCR, serpin peptidase inhibitor, clade E, member 1 (SERPINE1), and SELP were upregulated in the valve cusp at the protein level (P < .05). Messenger RNA composition in the vein wall within the valve cusp was similar to the prevalve and postvalve vein wall for all genes, except for two times overexpressed ICAM1 (P < .05). Substantial differences within the proteome between the study zones were observed with mass spectrometry.

CONCLUSIONS

The biological properties of the valve cusp, vein wall within the valve cusp, and vein wall beyond the valve cusp are different. The endothelium of the valve cusps of a normal competent deep venous valve may be naturally less thrombogenic compared with the vein wall. The endothelium of the valve cusp may have a higher potential to interact with white blood cells compared with the vein wall. Mass spectrometry demonstrates substantial differences in the proteome between the vein wall and the valve cusps that were not anticipated before. (J Vasc Surg Venous Lymphat Disord 2021;9:770-80.) CLINICAL RELEVANCE: Deep vein thrombosis (DVT) is a major cause of mortality, morbidity, and impaired quality of life. Multiple risk factors have been identified, although their relative weight and pathophysiologic interactions remain obscure. Many patients with multiple risk factors for DVT never develop this condition. Conversely, in numerous cases DVT cannot be attributed to any known clinical risk factor. The molecular mechanisms that initiate DVT are unclear. An improved understanding of the normal biology of human deep veins will serve as an important foundation for new hypotheses of the pathogenesis of DVT. The latter may suggest new projects on novel therapeutic strategies.

Doppler ultrasonographic evaluation of lower limbs deep-vein thrombosis in a teaching hospital, Northwestern Nigeria

Background

Deep-venous thrombosis (DVT) of lower limbs is one of the most common causes of death caused by pulmonary embolism. Many medical and surgical disorders are complicated by DVT. B-mode and color Doppler imaging are needed for the early diagnosis of DVT to prevent complications and sequalae of DVT.

Objectives

The objectives of this study are to evaluate the role of Doppler ultrasound in diagnosing DVT of lower limbs and to study the spectrum of findings in patients with DVT in Zaria.

Methodology

A retrospective study was carried out on patients who had Venous Doppler Scan in the Department of Radiology ABUTH, Zaria, Nigeria, for suspected DVT over a period of 4 years from February 2014 to January 2018. Scans were done using DC-3 and DC-6 Mindray Ultrasound machines (2009 and 2013 Models, respectively, Shantou, China) coupled with high-frequency (7.5-12 MHz) linear and low-frequency curvilinear (2-5 MHz) transducers. Analysis of cases of DVT was performed in terms of age, sex, clinical features, predisposing conditions, anatomic distribution, stage, and pattern of thrombus involvement in the veins. Data were analyzed using the SPSS version 20.0 and value of P < 0.005 was considered as statistically significant.

Results

A total of 252 patients' results were reviewed which consisted of 122 males (48.4%) and 130 females (51.6%). The patients' ages ranged from 11 to 80 years, averaging 45.5 ± 9.56 years. The most common indication for Doppler request was leg swellings. The most common risk factor for DVT was malignancy (36%), cardiac disorders (18%), and traumas (14%). Sixty-six (61%) cases showed left-sided and 26 (24%) right-sided, whereas 16 (15%) cases showed bilateral lower limb involvement. Predominant thrombus was above-knee region with 54% in the superficial femoral vein. Chronic stage was seen in 46 (42%) cases, subacute in 44 (41%) cases, and acute in 18 (17%) cases.

Conclusion

Middle-aged females, left-sided leg, and above-knee segment were predominantly affected with DVT; hence, this buttresses the need for Doppler ultrasound in the diagnosis of DVT in all patients.

Inferior vena cava syndrome in neonates: An evidence-based systematic review of the literature

Neonatal inferior vena cava syndrome (IVCS), though uncommon, is associated with significant morbidity and mortality. Information on risk factors, diagnosis, treatment, and outcomes is limited. This review comprised 61 neonates across 33 reports. Thrombosis occurred in 98% and 42% involved a central venous catheter. Diagnosis was mainly established by ultrasound in 82%. Therapeutically, heparin was employed in 36% and thrombolysis in 18% of the cases. The overall mortality was 23%. An algorithm of clinical signs, investigation, and management is presented. Well-designed prospective studies are needed to establish a concrete investigational approach to neonatal IVCS and institute safe, evidence-based treatment.

May-Thurner syndrome: History of understanding and need for defining population prevalence

Patients with May-Thurner syndrome (MTS) are at elevated risk of developing an extensive left iliofemoral deep vein thrombosis (DVT; localized blood clot) due to an anatomical variant where the right common iliac artery compresses the left common iliac vein against the lumbar spine. While MTS was initially presumed to be rare when it was first anatomically defined in 1957, case reports of this syndrome have recently become more frequent, perhaps due to improved imaging techniques allowing for enhanced visualization of the iliac veins. Still, the population burden of this condition is unknown, and there is speculation it may be higher than generally perceived. In the present review, we (a) review history of how MTS became recognized, (b) describe practical challenges of studying MTS in population-based settings due to the specialized imaging required for diagnosis, (c) discuss why the contribution of MTS to DVT may be underestimated, (d) describe uncertainty regarding the degree of venous compression which leads to DVT, and (e) outline future research needs. Our goal is to raise awareness of MTS and spark additional research into the epidemiology of this condition, which may be an underappreciated causative venous thromboembolism risk factor.

Incidence of deep vein thrombosis from screening by venous ultrasonography in Japanese patients

The aim of the present study was to investigate the incidence of deep vein thrombosis (DVT) patients in a Japanese population by screening them with venous ultrasonography. This retrospective, single-center analysis examined 963 patients who underwent venous ultrasonography in 2015. The primary outcome was the incidence of DVT, and secondary outcomes were predictive factors of DVT in patient characteristics, treatment strategy for DVT patients, and proportion of post thrombotic syndrome (PTS). The overall incidence rate of DVT was 10.3% (100/963). The location of thrombus was the iliac vein in 3.6% (n = 35), the femoral vein in 4.4% (n = 43), and the calf vein in 8.2% (n = 79) of the patients. The main complaint or purpose of examination was perioperative screening in 37% of the patients, leg edema and/or limb swelling in 27% of the patients, and skin disease in 8% of the patients. In a multivariate analysis, the incidence of DVT was significantly higher in the hospitalization group and the "having symptoms" group. Fifty percent of DVTs received treatment, and almost all therapies were medical treatment with oral anticoagulants (OAC). Within a three-year follow-up period, the proportion of PTS was 27% with no significant difference between anticoagulation or non-anticoagulation patients; the risk of PTS was in concomitant varicose veins. In conclusion, of the patients, 10.3% were diagnosed with DVT, and only half received treatment with only anticoagulation.

Incidence and potential predictors of thromboembolic events in epithelial ovarian carcinoma patients during perioperative period

OBJECTIVE

To assess the incidence and the risk factors of venous thromboembolism (VTE) in patients with epithelial ovarian carcinoma (EOC) during the perioperative period.

METHODS

A retrospective analysis was conducted on the patients with epithelial ovarian cancer treated in our hospital, between January 2017 and July 2019, and a comprehensive review of the medical documentation was performed to collect relevant data. We then analyzed the related factors of the thrombosis in the EOC patients, using univariate and multivariate analysis to identify significant risk factors for VTE, and bootstrap resampling method was used to verify the multivariate analysis results. The ROC curve methods were conducted to evaluate the diagnostic value for the prediction of VTE.

RESULTS

We analyzed 233 cases of patients with EOC, of whom the incidence of VTE was 11.16%. According to multivariate and 5000 bootstrap samples analysis, preoperative D-dimer levels (>4.215 μg/ml, p = 0.041 and p = 0.032) and comorbid of cerebral infarction (p < 0.001 and p < 0.001) had statistical significance in predicting VTE events; bootstrap analysis also found the Alb, CA125, OCCC had statistical significance. While According to multivariate and 5000 bootstrap samples analysis, age (>50.5 years old, p = 0.019 and p = 0.002) and nonoptimal debulking surgery (p = 0.007 and p = 0.002) showed significance in predicting VTE after surgery; bootstrap analysis also found the D-dimer levels (>4.215 μg/ml) and tuberculosis had statistical significance.

CONCLUSION

More effective thromboprophylaxis and pre-test assessment is necessary for EOC patients. For prediction VTE events, D-dimer levels (>4.215 μg/ml) were the independent predictors before operation. Age and debulking surgery were the independent predictors post operation.

Incidence and Risk Factors of Symptomatic Venous Thromboembolism Following Foot and Ankle Surgery

BACKGROUND:

The incidence rate of venous thrombotic events (VTEs) following foot and ankle surgery is low. Currently, there is no consensus regarding postoperative prophylaxis or evidence to support risk stratification.

METHODS:

A 2-part study assessing the incidence and factors for the development of VTE was conducted: (1) a retrospective observational cohort study of 22 486 adults to calculate the overall incidence following foot and/or ankle surgery from January 2008 to May 2011 and (2) a retrospective matched case-control study to identify risk factors for development of VTE postsurgery. One control per VTE case matched on age and sex was randomly selected from the remaining patients.

RESULTS:

The overall incidence of VTE was 0.9%. Predictive risk factors in bivariate analyses included obesity, history of VTE, history of trauma, use of hormonal replacement or oral contraception therapy, anatomic location of surgery, procedure duration 60 minutes or more, general anesthesia, postoperative nonweightbearing immobilization greater than 2 weeks, and use of anticoagulation. When significant variables from bivariate analyses were placed into the multivariable regression model, 4 remained statistically significant: adjusted odds ratio (aOR) for obesity, 6.1; history of VTE, 15.7; use of hormone replacement therapy, 8.9; and postoperative nonweightbearing immobilization greater than 2 weeks, 9.0. The risk of VTE increased significantly with 3 or more risk factors ( P = .001).

CONCLUSION:

The overall low incidence of VTE following foot and ankle surgery does not support routine prophylaxis for all patients. Among patients with 3 or more risk factors, the use of chemoprophylaxis may be warranted.

LEVEL OF EVIDENCE:

Level III, retrospective case series.

Left iliac vein compression is not associated with infrainguinal deep venous thrombosis but is associated with iliac vein involvement

OBJECTIVE

The purpose of this study was to investigate whether left iliac vein (LIV) compression had similar correlation with the risk of left iliac deep venous thrombosis (DVT; iliac vein involvement) and infrainguinal DVT (without iliac vein involvement).

METHODS

A retrospective analysis of records and enhanced computed tomography images was conducted of 278 patients with left-sided DVT (iliac DVT, 228 patients; infrainguinal DVT, 50 patients) and 232 control patients without DVT on either side. The influences of LIV compression on the risk of left iliac DVT and infrainguinal DVT were investigated using logistic regression analysis.

RESULTS

Mean percentage compression of the LIV in left iliac DVT (74.64% ± 0.99%) patients was significantly higher than in non-DVT patients (53.42% ± 1.49%; P < .01). However, mean percentage compression of the LIV in left infrainguinal DVT patients (45.37% ± 2.71%) was significantly lower than in non-DVT patients (53.42% ± 1.49%; P < .01). LIV compression was associated with increased odds of left iliac DVT (odds ratio, 1.88; 95% confidence interval, 1.64-2.15; P < .01) for each 10% increase in percentage compression of the LIV. However, LIV compression was not associated with increased odds of infrainguinal DVT (odds ratio, 0.89; 95% confidence interval, 0.76-1.03; P = .126).

CONCLUSIONS

Left iliac DVT patients had more severe LIV compression than left infrainguinal DVT patients did. LIV compression was not associated with development of left infrainguinal DVT, but it did correlate with the presence of left-sided DVT with iliac vein involvement.

Epidemiology, Pathophysiology, and Natural History of Pulmonary Embolism

Pulmonary embolism (PE) is a common and potentially deadly form of venous thromboembolic disease. It is the third most common cause of cardiovascular death and is associated with multiple inherited and acquired risk factors as well as advanced age. The prognosis from PE depends on the degree of obstruction and hemodynamic effects of PE and understanding the pathophysiology helps in risk-stratifying patients and determining treatment. Though the natural history of thrombus is resolution, a subset of patients have chronic residual thrombus, contributing to the post-PE syndrome.

Ultrasound for Lower Extremity Deep Venous Thrombosis

Venous ultrasound is the standard imaging test for patients suspected of having acute deep venous thrombosis (DVT). There is variability and disagreement among authoritative groups regarding the necessary components of the test. Some protocols include scanning the entire lower extremity, whereas others recommend scans limited to the thigh and knee supplemented with serial testing. Some protocols use gray-scale ultrasound alone, whereas others include Doppler interrogation. Point-of-care ultrasound is recommended in some settings, and there is heterogeneity of these protocols as well. Heterogeneity of recommendations can lead to errors including incorrect application of guidelines, confusion among requesting physicians, and incorrect follow-up. In October 2016, the Society of Radiologists in Ultrasound convened a multidisciplinary panel of experts to evaluate the current evidence to develop recommendations regarding ultrasound protocols for DVT and the terminology used to communicate results to clinicians. Recommendations were made after open discussion and by unanimous consensus.

The panel recommends a comprehensive duplex ultrasound protocol from thigh to ankle with Doppler at selected sites rather than a limited or complete compression-only examination. This protocol is currently performed in many facilities and is achievable with standard ultrasound equipment and personnel. The use of these recommendations will increase the diagnosis of calf DVT and provide better data to explain the presenting symptoms. The panel recommends a single point-of-care protocol that minimizes underdiagnoses of proximal DVT.

The panel recommends the term chronic postthrombotic change to describe the residual material that persists after the acute presentation of DVT to avoid potential overtreatment of prior thrombus.

Adoption of a single standardized comprehensive duplex ultrasound and a single point-of-care examination will enhance patient safety and clinicians’ confidence.

Treatment of Femoral Vein Obstruction Concomitant with Iliofemoral Stenting in Patients with Severe Post-thrombotic Syndrome

BACKGROUND

The aim was to assess the clinical and anatomical outcomes of iliofemoral stenting, with concomitant femoral stenting or balloon angioplasty alone, in patients with severe post-thrombotic syndrome (PTS) and compromised inflow.

METHODS

A database of patients with severe PTS who successfully underwent endovascular iliofemoral stenting was reviewed retrospectively. Patients with impaired inflow with chronic post-thrombotic obstructive lesions in the femoral vein (FV), but patent profunda vein, were selected and divided into two groups: the FV stenting (FV-S) group and the FV angioplasty (FV-A) group. Patients in the FV-S group were treated with concomitant iliofemoral and FV stenting, and patients in the FV-A group were treated with iliofemoral stenting and balloon angioplasty alone of the obstructed femoral vein. The clinical and stent outcomes were recorded and compared in the two groups.

RESULTS

There were 45 patients in the FV-S group and 69 patients in the FV-A group. The groups were well matched for age, gender, and diseased limbs. The pre-procedural symptoms, CEAP classifications, VCSS scores, Villalta scores, and prevalence of active ulcers were also similar between the two groups. Immediate failure (<30 days post-procedure) in the femoral segment occurred more frequently in the FV-A group (70% in FV-A group vs. 24% in FV-S group, p < .001); however, all treated femoral vein segments had occluded at 12 months. There was no significant difference between the FV-S and FV-A groups in cumulative primary and secondary patency rates of the iliofemoral stent at 3 years (55% vs. 52%, p = .71, and 77% vs. 85%, p = .32, respectively). Complete pain relief, swelling relief, VCSS score, Villalta score, and freedom from ulcers at a median of 22 months (1-48 months) following the procedure were similar in the two groups.

CONCLUSIONS

Stent placement to treat post-thrombotic iliofemoral obstruction with concomitant obstructed femoral vein but patent profunda vein shows cumulative patency rates and clinical outcomes similar to previous reports. Adjunctive femoral stenting or angioplasty of the obstructed femoral vein does not appear to improve clinical or stent outcomes in patients with severe PTS.

Performance of wells score to predict deep vein thrombosis and pulmonary embolism in endurance athletes

INTRODUCTION

There are an increasing number of reports describing deep vein thrombosis (DVT) and/or pulmonary embolism (PE) in otherwise healthy endurance athletes. The Wells score is the most commonly used clinical prediction rule to diagnose DVT/PE in clinical populations. However, the Wells score may have limited utility for recognition of DVT/PE in athletes, contributing to missed or delayed diagnosis.

OBJECTIVE

We performed an analysis of the ability of the Wells score to identify DVT/PE events in athletes through a review of published case reports.

METHODS

A systematic search of the literature yielded 11 case reports.

RESULTS

The Wells score had a 100% failure rate in identifying athletes with DVT (0/6) and PE (0/5), resulting in a delayed diagnosis for DVT of 20 ± 14 days. Retrospectively removing 'differential diagnosis' from the clinical prediction rule for DVT changed the Wells score median from 0 (range: -1 to 0) to 2 (range: 1 to 2); the threshold for predicting DVT as 'likely'. There were limited clinical characteristics captured in the Wells score for PE that were applicable to athletes, highlighting the need for reappraisal. Although the Wells score failed to accurately triage athletes with known DVT and/or PE, the addition of a D-dimer value (mean: 1566 ± 758ng/dL) to the Wells score correctly identified 9/9 athletes.

CONCLUSIONS

The Wells score had a 100% failure rate for triaging athletes with known DVT/PE. When performed, D-dimer adequately facilitated the additional diagnostic testing required for a timely diagnosis of DVT/PE in athletes. Improving awareness of an atypical presentation of thrombotic events in athletes may reduce the widespread underestimation of DVT/PE among athletes and facilitate the additional testing required for a timely diagnosis.

Recurrent Deep Vein Thrombosis After the First Venous Thromboembolism Event: A Single-Institution Experience

BACKGROUND We investigated the frequency, clinical presentation, risk factors, and outcome after the first deep vein thrombosis (DVT) event. MATERIAL AND METHODS A retrospective study was conducted for patients with DVT between 2008 and 2012 with a 1-year follow-up. Patients were divided into 2 groups: single vs. recurrent DVT (RDVT). RESULTS Of the 6420 patients screened for DVT, 662 (10.3%) had DVT. RDVT constituted 22% of cases. A single event was more frequent in left lower limb DVT (p=0.01), while RDVT cases had more bilateral DVT (p=0.01). Recurrent pulmonary embolism (PE) and comorbidities were significantly higher in the RDVT group (P<0.05). Protein C, protein S, and anti-thrombin III deficiency were higher in patients with RDVT (P<0.05). Post-thrombotic syndrome was significantly higher among RDVT cases (p=0.01). In addition, obesity, abnormal coagulation, and prior history of PE and bilateral DVT were found to be independent predictors of RDVT. The PE rate was greater with RDVT than those with single events (22% vs. 9%, p=0.001); however, during follow-up and after adjustment for age and sex, this effect was statistically insignificant (adjusted HR 1.23, 95% CI 0.43-3.57, p=0.68). The age- and sex-adjusted mortality rate was higher in patients with single events with a HR 2.3; 95%CI 1.18-4.54 (p=0.01); however, this effect disappeared after adjusting for the duration of warfarin therapy (p=0.22). CONCLUSIONS Patients with RDVT are common and have characteristic features that required more attention and further evaluation. These findings should help identifying high-risk patients and set effective preventive measures for RDVT that may revise the duration of warfarin therapy.

An Unusual Endovascular Therapeutic Approach for a Rare Case of May-Thurner Syndrome

Patient: Male, 69

Final Diagnosis: May-Thurner syndrome secondary to left common iliac artery aneurysm

Symptoms: Left lower extremity edema • left lower extremity erythema • left lower extremity pain

Medication: —

Clinical Procedure: Endovascular aneurysm repair (EVAR) of the infra-renal abdominal aorta aneurysm and right common iliac artery aneurysm

Specialty: Cardiology

Clinical implications of the anatomical variation of deep venous thrombosis

Introduction

Little is known about the anatomic variation and its implication in patients with lower limb deep venous thrombosis (DVT). We studied the clinical presentation, site of thrombosis and risk factors based on the anatomic distribution of lower limb DVT.

Methods

A retrospective analysis of clinically suspected DVT cases was conducted between 2008 and 2012. DVT was categorized by the location of the thrombosed segment and limb involved. The DVT anatomic segments were assessed according to left-to-right ratio, predisposing factors and clinical presentations.

Results

A total of 637 patients with DVT were included with a mean age of 50 ± 17 years (51%; females). The most frequently thrombosed segments were popliteal, posterior tibial and profunda femoris veins. DVT was more common at the left side, with a left-to-right ratio of 1.5:1. Bilateral DVT cases (38.5%) had more prior history of DVT as compared to left- (20.3%) and right-sided DVTs (22.6%); p = 0.01. Bilateral DVT was complicated more with post-thrombotic syndrome (leg ulcer) ( p = 0.02). The rates of pulmonary embolism (25%) and mortality (23.1%) were significantly higher for bilateral DVT in comparison to left- and right-sided DVT. Abnormal coagulation profile was significantly associated with posterior tibial DVT (81% vs. 71.4%; p = 0.01) as compared to patients with normal coagulation profile.

Conclusion

Lower limb DVTs are more common at the left side; however, patients with bilateral DVT have higher frequency of recurrence, post-thrombotic syndrome, pulmonary embolism and mortality. The anatomic segments of DVT show specific distribution depending on the predisposing factors. These findings could improve our understanding of the pathophysiology and management of DVT patients.

Clinical features and risk factor analysis for lower extremity deep venous thrombosis in Chinese neurosurgical patients

Background:

Deep venous thrombosis (DVT) contributes significantly to the morbidity and mortality of neurosurgical patients; however, no data regarding lower extremity DVT in postoperative Chinese neurosurgical patients have been reported.

Materials and Methods:

From January 2012 to December 2013, 196 patients without preoperative DVT who underwent neurosurgical operations were evaluated by color Doppler ultrasonography and D-dimer level measurements on the 3^rd, 7^th, and 14^th days after surgery. Follow-up clinical data were recorded to determine the incidence of lower extremity DVT in postoperative neurosurgical patients and to analyze related clinical features. First, a single factor analysis, Chi-square test, was used to select statistically significant factors. Then, a multivariate analysis, binary logistic regression analysis, was used to determine risk factors for lower extremity DVT in postoperative neurosurgical patients.

Results:

Lower extremity DVT occurred in 61 patients, and the incidence of DVT was 31.1% in the enrolled Chinese neurosurgical patients. The common symptoms of DVT were limb swelling and lower extremity pain as well as increased soft tissue tension. The common sites of venous involvement were the calf muscle and peroneal and posterior tibial veins. The single factor analysis showed statistically significant differences in DVT risk factors, including age, hypertension, smoking status, operation time, a bedridden or paralyzed state, the presence of a tumor, postoperative dehydration, and glucocorticoid treatment, between the two groups (P < 0.05). The binary logistic regression analysis showed that an age greater than 50 years, hypertension, a bedridden or paralyzed state, the presence of a tumor, and postoperative dehydration were risk factors for lower extremity DVT in postoperative neurosurgical patients.

Conclusions:

Lower extremity DVT was a common complication following craniotomy in the enrolled Chinese neurosurgical patients. Multiple factors were identified as predictive of DVT in neurosurgical patients, including the presence of a tumor, an age greater than 50 years, hypertension, and immobility.

Analysis of 1,338 Patients with Acute Lower Limb Deep Venous Thrombosis (DVT) Supports the Inadequacy of the Term "Proximal DVT"

OBJECTIVE/BACKGROUND

For decades acute lower limb deep venous thrombosis (DVT) has been subdivided into distal DVT (isolated to the calf veins) and proximal DVT (extending above calf vein level). The aim of this study was to analyse the anatomical site and extent of thrombus in a large cohort of patients with acute DVT.

METHODS

A retrospective analysis of all patients aged >18 years, presenting with unilateral DVT according to duplex ultrasound investigation was performed at the University Hospital of Antwerp, Belgium (1994-2012). The anatomical site and extent of thrombus was registered and subdivided into five segments: calf veins (segment 1), popliteal vein (segment 2), femoral vein (segment 3), common femoral vein (segment 4), and iliac veins, with or without inferior vena cava (segment 5).

RESULTS

The median age of the 1,338 patients (50% male) included was 62 years (range 18-98 years). Left sided DVT was predominant (57%). DVT was limited to one segment in 443 patients, of whom 370 had DVT isolated to the calf veins (28% of total cohort). In 968 patients with what was previously called "proximal DVT", the median number of affected segments was three (range 1-5 segments). In this group iliofemoral DVT (at least involving segment four and/or five) was present in 506 patients (38% of total cohort), whereas the remaining patients had femoropopliteal DVT (at least in segment two and/or three but not in four or five). Iliofemoral DVT without thrombus in segments one and two was present in 160 patients (12% of total cohort).

CONCLUSION

This study illustrates the large diversity of thrombus distribution in patients previously described as having "proximal DVT". Therefore, this term should be abandoned and replaced with iliofemoral and femoropopliteal DVT. Patients with iliofemoral DVT (38%) could be considered for early clot removal; 12% of all patients with DVT would be ideal candidates for such intervention.

Clinical Significance of the Soleal Vein and Related Drainage Veins, in Calf Vein Thrombosis in Autopsy Cases with Massive Pulmonary Thromboembolism

OBJECTIVE

To clarify the histopathological characteristics of deep vein thrombosis (DVT) resulting in lethal pulmonary thromboembolism (PE).

SUBJECTS AND METHODS

We investigated 100 autopsy cases of PE from limb DVT. The distribution and chronology of DVT in each deep venous segment were examined. Venous segments were classified into three groups: iliofemoral vein, popliteal vein and calf vein (CV). The CV was subdivided into two subgroups, drainage veins of the soleal vein (SV) and non drainage veins of SV.

RESULTS

Eighty-nine patients had bilateral limb DVTs. CV was involved in all limbs with DVT with isolated calf DVTs were seen in 47% of patients. Fresh and organized thrombi were detected in 84% of patients. SV showed the highest incidence of DVTs in eight venous segments. The incidence of DVT gradually decreased according to the drainage route of the central SV. Proximal tips of fresh thrombi were mainly located in the popliteal vein and tibioperoneal trunk, occurring in these locations in 63% of limbs.

CONCLUSIONS

SV is considered to be the primary site of DVT; the DVT then propagated to proximal veins through the drainage veins. Lethal thromboemboli would occur at proximal veins as a result of proximal propagation from calf DVTs.

Pattern of Venous Thromboembolism Occurrence in Gynecologic Malignancy: Incidence, Timing, and Distribution a 10-Year Retrospective Single-institutional Study

The aim of this single-institutional 10-year retrospective study was to investigate the clinical pattern (incidence, type, timing, and location) of venous thromboembolism (VTE) in Chinese patients with gynecologic cancer. Cases were identified by searching institutional Electronic Discharge Database. A comprehensive review of medical documentation was then performed to collect relevant data. The detection of VTE was symptom-triggered. A total of 155 VTE events were identified out of 7562 cases over the past 10-year period in our hospital. The incidence of clinically significant VTE was 2.0% in gynecologic malignancy, with vulvar cancer (3.7%) and ovarian cancer (2.5%) being the high-risk types (P = 0.01, Chi-square test). Perioperative period (35.1%) and preoperation (29.1%) were the 2 incidence peaks. Seventeen cases of pulmonary embolism (PE) occurred prior to surgery. Ovarian cancer patients were more likely to present preoperative PE compared to other site of cancer (76.4%; P = 0.01, Chi-square test). More preoperative VTE cases were complicated by PE than those in the perioperative period (39.5% vs 17.3%, P = 0.02, Chi-square test). Bilateral lower extremity deep vein thrombosis (DVT) accounted for 32.6% and there existed a preponderance of left-sided DVT (47.5% vs 17.0%, ratio 2.79:1). Femoral vein (36.6%) was the most common location for DVT. About 2.0% of the Chinese patients with gynecologic carcinoma developed clinical VTE, mostly during perioperative period and the time of diagnosis. The true incidence might have been under-estimated due to several reasons. The need for increased patient education and awareness of VTE is of importance.

Compression of the right iliac vein in asymptomatic subjects and patients with iliofemoral deep vein thrombosis

OBJECTIVE

To evaluate right iliac vein and left iliac vein compression in asymptomatic subjects, right-sided and left-sided iliofemoral deep vein thrombosis patients.

METHODS

A retrospective analysis of records and computed tomography images was conducted in 200 asymptomatic subjects (male:female, 100:100). A prospective analysis was conducted in 79 consecutive deep vein thrombosis patients (left:right deep vein thrombosis, 47:32) who had undergone contrast-enhanced computed tomography examination. The minor diameter and percentage compression of the iliac vein were evaluated.

RESULTS

In asymptomatic subjects, 13.5% had right iliac vein compression >50%, 2.0% had right iliac vein compression >70%, mean compression was 23.48%; 45.0% had left iliac vein compression >50% and 17.0% had left iliac vein compression >70%, mean compression was 47.58%. Right iliac vein sandwiched between the right external iliac artery and the right internal iliac artery was the most common compression pattern (59.26%). Males had higher right iliac vein compression than the females (male:female, 26.29%:20.68%, P < 0.001). Mean percentage compression of the right iliac vein was higher in right deep vein thrombosis patients than in left deep vein thrombosis patients (right:left deep vein thrombosis, 48.54%:22.29%, P < 0.001).

CONCLUSION

Similar to left iliac vein compression, right iliac vein compression was a frequent imaging finding in CT and represented a normal anatomic pattern. Right deep vein thrombosis patients had more serious right iliac vein compression than left deep vein thrombosis patients, and further research is required on the association of right iliac vein compression with right iliofemoral deep vein thrombosis.

Differences in limb, age and sex of Chinese deep vein thrombosis patients

OBJECTIVE

Recently, the differences in age or sex of deep vein thrombosis (DVT) patients have been widely debated. However, close analyses of the differences in limb, age and sex of Chinese DVT patients have been scarcely reported. The purpose of this research is to study the differences in limb, age and sex of DVT patients.

METHODS

A total of 783 consecutive DVT patients were retrospectively reviewed. Patients with an acute presentation of DVT were diagnosed by means of compression ultrasonography or venography. Clinical characteristics and provoked risk factors were analyzed.

RESULTS

There were three frequency peaks including two smaller peaks at age 20-24 and 70-74 years, and the largest peak at age 45-59 years. The most significant risk factors affecting different age groups were as follows: pregnancy/puerperium for age ≤ 39; fracture and hysterectomy for age 40-64; fracture and malignancy for age ≥ 65. DVT frequency rate provoked by malignancy was higher in right DVT than left DVT (15.8% vs. 4.6%; p < 0.001). Left DVT was more common than right DVT (582 vs. 158). Left DVT tended to occur in females (male:female, 40.5%:59.5%), and right DVT in males (male:female, 74.7%:25.3%). DVT provoked by pregnancy/puerperium (56/63, 88.9%) or hysterectomy (27/30, 90.0%) was mostly located in left limb.

CONCLUSION

It is necessary to pay more attention to thromboprophylaxis for patients with the risk factors of pregnancy/puerperium, hysterectomy, fracture and malignancy, especially those over the age of 65. And further research into the cause of limb, age and sex differences in DVT occurrence is needed.

Comparison of Simultaneous and Alternate Bilateral Pneumatic Compression in Hemodynamic Effects and Thromboprophylaxis After Total Knee Arthroplasty

In this randomized trial, we compared the hemodynamic effects of 2 different methods of bilateral sequential pneumatic compression (Simultaneous compression with Fixed cycling rate [SF] vs Alternate compression with Adjusted cycling rate [AA]) and investigated whether venous flow augmentation influenced deep vein thrombosis (DVT) development in patients undergoing total knee arthroplasty. Pneumatic compression was started on the operation day and applied to discharge. A total of 108 limbs was evaluated by computed tomographic angiography and duplex ultrasound. Augmented peak volume flow (P = .008), expelled total volume (P < .001), and expelled peak volume (P < .001) were significantly larger in group SF. The DVT developed in 35 (32.4%) limbs, and they were neither symptomatic nor ileofemoral in location. The enhanced hemodynamic parameters did not influence the DVT development. In conclusion, group SF showed superior hemodynamic efficacy, but this superiority may not be a surrogate for better thromboprophylaxis.

[Incidence and distribution of 1026 lower limb venous thrombi diagnosed by ultrasonography in 3263 patients with cancer]

The study objective was to evaluate the incidence, characteristics and distribution of lower limb deep venous thrombi diagnosed by ultrasound among known cancer patients, in order to determine additional criteria that could be used to help select patients with unprovoked deep venous thrombosis caused by occult cancer.

PATIENTS AND METHODS

From January 2001 to May 2012, standardized report forms (n=38,424) were entered into a database. A total of 3263 report forms corresponding to cancer patients with suspected venous thrombo-embolic disease were selected from which 1026 cases of deep venous thrombosis were diagnosed by ultrasonography. Baseline characteristics, incidence, and anatomic distribution of venous thrombi were analyzed.

RESULTS

For 3263 patients with cancer, the venous thrombosis incidence was: total 31.4% (n=1026), proximal 14.5% (n=472), bilateral 8.5% (n=278) and multiple venous sites 4.6% (n=149). The rate of clinical suspicion of pulmonary embolism was 49.9% (n=1628). For 1026 patients with thrombosis, proximal thrombi were nearly as frequent as distal thrombi, with 17.6% (n=181) iliocaval thrombi. Gastrocnemial, popliteal and femoral veins were almost equally concerned by thrombosis with respective rates of 28.7% (n=278), 27.1% (n=294) and 25.6% (n=263). Superficial veins were concerned in 23.5% (n=241). Partial or floating clots occurred frequently in 4 localizations: common femoral, external iliac, femoral and popliteal veins.

CONCLUSION

Proximal, multiple, partial, mobile thrombi, and such unusual locations as gastrocnemial or superficial thromboses, are potentially indicators for selecting patients that may benefit from a cancer check-up because their venous thrombosis could be due to cancer.

Prospective analysis of incidence, extent and chronicity of lower extremity venous thrombosis

OBJECTIVE

This study was designed to determine all variables related to lower extremity deep venous thrombosis (DVT) to be used as reference in patients examined in a hospital setting.

METHODS

Consecutive patients presented with signs and symptoms of venous thromboembolism over a one-year period, examined in our university hospital. Patients' demographics and clinical characteristics in a data base organized to answer all the pertinent questions.

RESULTS

There were 2594 patients. Thrombosis was found in 348 (13.4%) of which 249 were acute and 72 had chronic luminal changes. Unilateral thrombosis was found in 268 and bilateral in 80. Acute DVT and/or chronic changes were more common on the left limb. Chronic thrombosis was more prevalent in the proximal veins. Acute thrombosis was more often found in the inpatients. Both acute DVT and chronic changes were found in 27 patients (7.8%) of whom 15 were bilateral.

CONCLUSIONS

Various patterns of thrombosis are found in both inpatients and outpatients with the former having a higher incidence of acute events. Acute, chronic and recurrent thrombosis are very frequent and very important to report as they could change the management of the patients.

Iliac vein compression as risk factor for left- versus right-sided deep venous thrombosis: case-control study

PURPOSE

To determine if compression of the left common iliac vein (LCIV) by the right common iliac artery is associated with left-sided deep venous thrombosis (DVT).

MATERIALS AND METHODS

This institutional review board-approved case-control study was performed in a cohort of 230 consecutive patients (94 men, 136 women; mean age, 57.5 years; range, 10-94 years) at one institution who had undergone contrast material-enhanced computed tomography of the pelvis prior to a diagnosis of unilateral DVT. Demographic data and information on risk factors were collected. Two board-certified radiologists determined iliac vein compression by using quantitative measures of percentage compression {[1 minus (LCIV diameter at point of maximal compression/distal right common iliac vein diameter)] times 100%}, as well as qualitative measures (none, mild, moderate, severe), with estimates of measurement variability. Logistic regression analysis was performed (independent variable, left vs right DVT; dependent variable, iliac vein compression). Cutpoints of relevant compression were evaluated by using splines. Means (with 95% confidence intervals [CIs]) and odds ratios (ORs) (and 95% CIs) of left DVT per 1% increase in percentage compression were calculated.

RESULTS

Patients with right DVT were more likely than those with left DVT to have a history of pulmonary embolism. Overall, in all study patients, mean percentage compression was 36.6%, 66 (29.7%) of 222 had greater than 50% compression, and 16 (7.2%) had greater than 70% compression. At most levels of compression, increasing compression was not associated with left DVT (adjusted ORs, 1.00, 0.99, 1.02) but above 70%, LCIV compression may be associated with left DVT (adjusted ORs, 3.03, 0.91, 10.15).

CONCLUSION

Increasing levels of percentage compression were not associated with left-sided DVT up to 70%; however, greater than 70% compression may be associated with left DVT.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12111580/-/DC1.

Extrinsic compression of left iliac vein does not predict the development of post thrombotic syndrome in left side deep venous thrombosis

Purpose

Left side deep venous thrombosis (DVT) is associated with May-Thurner's anatomical variation and is often instigated by invasive treatment. The aim of this study is to analyze the influence of left iliac vein narrowness on incidence of post thrombotic syndrome (PTS) that developed after left side DVT.

Methods

Forty-one left side DVT cases that were followed up for more than 1 year were enrolled. The iliac vein narrowness was measured by the shortest distance from the right iliac artery to the 5th lumbar vertebra overlying left iliac vein in computed tomography (CT) scan. The incidence of PTS was measured by phone-call history taking for specific symptoms of PTS. The means of the shortest distance were compared by independent t-test.

Results

The number of PTS cases was eleven (26.8%). The level of thrombus, demographic data and other risk factors were similar in both PTS and non-PTS groups except the mean risk factor score. The mean of the shortest distance of PTS group and non-PTS group were 5.56 mm and 5.89 mm, respectively.

Conclusion

The degree of left iliac vein narrowness measured by the shortest distance from the right iliac artery and the 5th lumbar vertebral body was not a predictive factor for PTS.

The Anticoagulation of Calf Thrombosis (ACT) project: study protocol for a randomized controlled trial

BACKGROUND

Half of all lower limb deep vein thrombi (DVT) in symptomatic ambulatory patients are located in the distal (calf) veins. While proximal disease warrants therapeutic anticoagulation to reduce the associated risks, distal DVT often goes untreated. However, a proportion of untreated distal disease will undoubtedly propagate or embolize. Concern also exists that untreated disease could lead to long-term post thrombotic changes. Currently, it is not possible to predict which distal thrombi will develop such complications. Whether these potential risks outweigh those associated with unrestricted anticoagulation remains unclear. The Anticoagulation of Calf Thrombosis (ACT) trial aims to compare therapeutic anticoagulation against conservative management for patients with acute symptomatic distal deep vein thrombosis.

METHODS

ACT is a pragmatic, open-label, randomized controlled trial. Adult patients diagnosed with acute distal DVT will be allocated to either therapeutic anticoagulation or conservative management. All patients will undergo 3 months of clinical and assessor blinded sonographic follow-up, followed by 2-year final review. The project will commence initially as an external pilot study, recruiting over a 16-month period at a single center to assess feasibility measures and clinical event rates. Primary outcome measures will assess feasibility endpoints. Secondary clinical outcomes will be collected to gather accurate data for the design of a definitive clinical trial and will include: (1) a composite endpoint combining thrombus propagation to the popliteal vein or above, development of symptomatic pulmonary embolism or sudden death attributable to venous thromboembolic disease; (2) the incidence of major and minor bleeding episodes; (3) the incidence of post-thrombotic leg syndrome at 2 years using a validated screening tool; and (4) the incidence of venous thromboembolism (VTE) recurrence at 2 years.

DISCUSSION

The ACT trial will explore the feasibility of comparing therapeutic anticoagulation to conservative management in acute distal DVT, within a modern cohort. We also aim to provide contemporary data on clot propagation, bleeding rates and long-term outcomes within both groups. These results will inform the conduct of a definitive study if feasibility is established.

[Incidence and distribution of venous thrombosis of the lower limbs diagnosed by duplex ultrasonography after total hip or total knee arthroplasty, and hip fracture surgery. Results from 5981 exams and 2123 cases of venous thrombosis over 10 years]

AIM

To determine the incidence and distribution of lower limb venous thrombosis diagnosed by duplex ultrasonography, including calf exploration, after total hip or knee replacement or hip fracture, and to compare them with the venographic results reported by recent randomized control trials testing new antithrombotic drugs.

PATIENTS AND METHODS

From January 2001 to December 2009, 30,510 standardized report forms incremented a database from which files corresponding to major orthopaedic surgery were selected: 1652 after total hip replacement (THR), 1440 after total knee replacement (TKR) and 2889 after hip fracture (HF). Base-line characteristics, incidence and anatomic distribution of venous thrombosis were analysed in the three populations.

RESULTS

Systematic screening was applied for 95.1% of the exams (n=5689). Incidence of total and proximal venous thrombosis was, respectively, 27.8% (n=460) and 2.8% (n=46) for THR, 32.5% (n=939) and 4.4% (n=126) for HF, and 50.3% (n=724) and 3.8% (n=55) for TKR. Venous thrombosis was distal in 89.3% (n=1896). More than half (n=1014) of distal venous thromboses were strictly muscular soleal locations. Ilio-caval thrombosis incidence was 0.18% (n=11), and superficial venous thrombosis incidence was 1.5% (n=89).

CONCLUSION

This study shows that incidence and distribution of venous thromboses diagnosed with a complete and standardized duplex ultrasonographic screening are very close to the rates published with venographic screening in recent trials.

Prospective determination of candidates for thrombolysis in patients with acute proximal deep vein thrombosis

PURPOSE

To prospectively determine the distribution, extent, and age of venous thrombosis in patients presenting with acute signs and symptoms of venous thromboembolism and identify candidates for thrombolysis.

MATERIALS AND METHODS

Five hundred seventy-six consecutive patients (281 male, 295 female; mean age 58) referred for lower extremity deep vein thrombosis (DVT) assessment between November 2007 and April 2008 were included in the study. Documented cases of DVT were categorized by age (acute, chronic, and acute on chronic), anatomic location, and extent. Patients with iliofemoral and femoropopliteal DVT were evaluated for thrombolysis using standard criteria.

RESULTS

DVT was found in 19% of patients (112/576). Of these, 31 patients (27.7%, 31/112) had isolated calf DVT, 61 patients (54.5%, 61/112) had proximal vein thrombosis extending into the femoropopliteal venous segments, and 20 patients (17.9%, 20/112) presented with iliofemoral DVT. Using standard criteria, 12 patients were selected as potential candidates for pharmacomechanical thrombolysis (PhMT). This equated to an incidence of 2% (12/576) in the population studied, 11% of patients (12/112) with DVT, 26.1% of patients (12/46) presenting with acute proximal DVT, and 20% of patients (4/20) with iliofemoral DVT.

CONCLUSION

The incidence of potential candidates for thrombolysis is low. These data should be considered when recruiting centers to participate in ongoing clinical trials assessing the efficacy of these techniques.