The Wells rule and D-dimer for the diagnosis of isolated distal deep vein thrombosis

Predictive modeling of deep vein thrombosis risk in hospitalized patients: A Q-learning enhanced feature selection model

Deep vein thrombosis (DVT) represents a critical health concern due to its potential to lead to pulmonary embolism, a life-threatening complication. Early identification and prediction of DVT are crucial to prevent thromboembolic events and implement timely prophylactic measures in high-risk individuals. This study aims to examine the risk determinants associated with acute lower extremity DVT in hospitalized individuals. Additionally, it introduces an innovative approach by integrating Q-learning augmented colony predation search ant colony optimizer (QL-CPSACO) into the analysis. This algorithm, then combined with support vector machines (SVM), forms a bQL-CPSACO-SVM feature selection model dedicated to crafting a clinical risk prognostication model for DVT. The effectiveness of the proposed algorithm's optimization and the model's accuracy are assessed through experiments utilizing the CEC 2017 benchmark functions and predictive analyses on the DVT dataset. The experimental results reveal that the proposed model achieves an outstanding accuracy of 95.90% in predicting DVT. Key parameters such as D-dimer, normal plasma prothrombin time, prothrombin percentage activity, age, previously documented DVT, leukocyte count, and thrombocyte count demonstrate significant value in the prognostication of DVT. The proposed method provides a basis for risk assessment at the time of patient admission and offers substantial guidance to physicians in making therapeutic decisions.

To Compare the Effectiveness of Low-Molecular-Weight Heparin and Unfractionated Heparin in Reducing Lower Limb Girth in Deep Vein Thrombosis

INTRODUCTION

Treating deep vein thrombosis (DVT) using a once-daily dose of enoxaparin offers greater convenience and the possibility of home-based care for certain patients, as opposed to a continuous infusion of unfractionated heparin (UFH). The study aimed to determine the most cost-effective thromboprophylaxis between low-molecular-weight heparin (LMWH) and UFH for hospitalized patients.

MATERIALS AND METHODS

After obtaining clearance from the institutional ethical committee, the study was conducted in the Department of General Surgery, Sri Devaraj Urs Medical College, over a period of six months. Informed consent was obtained from all 46 patients included in this study. The participants were divided into two groups: group A received LMWH and group B received UFH.

RESULTS

The mean age in group A was 59.8 + 10.6 years and in group B was 54.9 + 12.3 years. There was no significant difference in the girth of the lower limb between the groups during the follow-up period (p > 0.05). In group A, there was a highly significant reduction in lower limb girth from day one to day five (p < 0.0001), day five to day 10 (p < 0.0001), and day one to day 10 (p < 0.0001). In group B, there was no significant reduction from day one to day five (p = 0.06), but there was a significant reduction from day five to day 10 (p = 0.001) and day one to day 10 (p = 0.001).

CONCLUSION

Treatment with LMWH as an anticoagulant significantly reduced the lower extremity girth and thrombus thickness in cases of DVT when compared to UFH.

Nomogram for predicting venous thromboembolism after spinal surgery

PURPOSE

This study aimed to establish a nomogram to predict the risk of venous thromboembolism (VTE), identifying potential risk factors, and providing theoretical basis for prevention of VTE after spinal surgery.

METHODS

A retrospective analysis was conducted on 2754 patients who underwent spinal surgery. The general characteristics of the training group were initially screened using univariate logistic analysis, and the LASSO method was used for optimal prediction. Subsequently, multivariate logistic regression analysis was performed to identify independent risk factors for postoperative VTE in the training group, and a nomogram for predict risk of VTE was established. The discrimination, calibration, and clinical usefulness of the nomogram were separately evaluated using the C-index, receiver operating characteristic curve, calibration plot and clinical decision curve, and was validated using data from the validation group finally.

RESULTS

Multivariate logistic regression analysis identified 10 independent risk factors for VTE after spinal surgery. A nomogram was established based on these independent risk factors. The C-index for the training and validation groups indicating high accuracy and stability of the model. The area under the receiver operating characteristic curve indicating excellent discrimination ability; the calibration curves showed outstanding calibration for both the training and validation groups. Decision curve analysis showed the clinical net benefit of using the nomogram could be maximized in the probability threshold range of 0.01-1.

CONCLUSION

Patients undergoing spinal surgery with elevated D-dimer levels, prolonger surgical, and cervical surgery have higher risk of VTE. The nomogram can provide a theoretical basis for clinicians to prevent VTE.

Establishment and validation of a nomogram predicting the risk of deep vein thrombosis before total knee arthroplasty

PURPOSE

This study aimed to analyze the independent risk factors contributing to preoperative DVT in TKA and constructed a predictive nomogram to accurately evaluate its occurrence based on these factors.

METHODS

The study encompassed 496 patients who underwent total knee arthroplasty at our hospital between June 2022 and June 2023. The dataset was randomly divided into a training set (n = 348) and a validation set (n = 148) in a 7:3 ratio. The least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression analysis were used to screen the predictors of preoperative DVT occurrence in TKA and construct a nomogram. The performance of the predictive models was evaluated using the concordance index (C-index), calibration curves, and the receiver operating characteristic (ROC) curves. Decision curve analysis was used to analyze the clinical applicability of nomogram.

RESULTS

A total of 496 patients who underwent TKA were included in this study, of which 28 patients were examined for lower extremity DVT preoperatively. Platelet crit, Platelet distribution width, Procalcitonin, prothrombin time, and D-dimer were predictors of preoperative occurrence of lower extremity DVT in the nomograms of the TKA patients. In addition, the areas under the curve of the ROC of the training and validation sets were 0.935 (95%CI: 0.880-0.990) and 0.854 (95%CI: 0.697-1.000), and the C-indices of the two sets were 0.919 (95%CI: 0.860-0.978) and 0.900 (95%CI: 0.791-1.009). The nomogram demonstrated precise risk prediction of preoperative DVT occurrence in TKA as confirmed by the calibration curve and decision curve analysis.

CONCLUSIONS

This Nomogram demonstrates great differentiation, calibration and clinical validity. By assessing individual risk, clinicians can promptly detect the onset of DVT, facilitating additional life monitoring and necessary medical interventions to prevent the progression of DVT effectively.

Incidence and risk factors of perioperative deep vein thrombosis in patients undergoing primary hip arthroplasty via the direct anterior approach

BACKGROUND

Deep vein thrombosis (DVT) is a frequent complication following hip arthroplasty. There still has been a lack of studies analyzing the perioperative risk factors of DVT following hip arthroplasty via direct anterior approach (DAA).

METHODS

Patients who underwent unilateral primary hip arthroplasty via DAA in our hospital from August 2015 to January 2022 were included. Patients' data, including demographic data, clinical features, past medical history, operative data, and laboratory data, were analyzed and compared between patients with and without DVT. Logistic regression analysis was conducted to identify the independent risk factors. Receiver operating characteristic (ROC) curve analysis was used to assess the best cutoff value of continuous variables with statistical significance.

RESULT

A total of 651 patients were included. The incidence of DVT before and after hip arthroplasty was 12.7% and 6.7%, respectively. Logistic regression analysis indicated that age ≥ 65 years (OR 4.594, 95% CI 1.994-10.587), women (OR 2.331, 95% CI 1.285-4.227), and cerebral infarction (OR 1.984, 95% CI 1.138-3.460) were independent risk factors for preoperative DVT. And age ≥ 65 years (OR 4.859, 95% CI 1.062-22.226), tumor (OR 3.622, 95% CI 1.108-11.841), and preoperative D-dimer (OR 1.040, 95% CI 1.004-1.078) were risk factors for postoperative DVT. The ROC curve analysis showed that the best cutoff value of preoperative D-dimer for the diagnosis of postoperative DVT is 1.44 mg/L.

CONCLUSIONS

The incidence of DVT in patients undergoing DAA hip arthroplasty was low and the occurrence of DVT before and after unilateral primary hip arthroplasty performed through DAA was related to multiple factors.

Age-adjusted D-dimer, clinical pre-test probability-adjusted D-dimer, and whole leg ultrasound in ruling out suspected proximal and calf deep venous thrombosis

D-dimer (DD) and ultrasonography (US) are part of the diagnostic workup for lower-extremity deep vein thrombosis (DVT). Recent studies have shown that adjusting DD level cut-offs by age or clinical pre-test probability (PTP) decreases the use of US. We compared diagnostic accuracy of PTP-adjusted DD and age-adjusted DD in 3883 patients (F: 61.1%; age: 65.3 ± 16.8 y) referred to our unit for clinically suspected DVT. All patients underwent clinical evaluation, DD, and US. Proximal DVT was detected in 477 (12.4%) patients, and distal DVT was isolated in 342 (8.9%) patients. In the remaining 3064 patients there were 23 venous thromboembolic events (0.75%, 95% CI: 0.50-1.12) during the 3-month follow-up. The specificities of DD, age-adjusted DD, and PTP-adjusted DD in patients without high PTP levels were 47% (95% CI: 45-49), 61% (95% CI: 59-62), and 67% (95% CI: 65-68), respectively. The negative predictive value (NPV) was 96% (95% CI: 95-97) for all diagnostic strategies. When only proximal DVTs were considered, the NPV increased to 99% (95% CI: 98-99). US was avoided in 37% (95% CI: 36-38) of patients with a fixed cut-off DD, 48% (95% CI: 47-50) with age-adjusted DD, and 52% (95% CI: 51-54) with PTP-adjusted DD. The failure rate for all DVTs of DD, age-adjusted DD, and PTP-adjusted DD was 2.0% (95% CI: 1.6-2.5), 2.7% (95% CI: 2.2-3.2), and 2.5% (95% CI: 2.1-3.0), respectively. Compared with the standard DD cut-off, both age-adjusted and PTP-adjusted DD reduced the proportion of patients who required US at the cost of a small increase in failure rate.

Incidence and risk factors of deep vein thrombosis in patients with spinal cord injury: a systematic review with meta-analysis

Background

Spinal cord injury (SCI) is a highly disabling disease with huge public health burden. The complications associated with it, especially deep vein thrombosis (DVT), further aggravate the disability.

Objective

To explore the incidence and risk factors of DVT after SCI, in order to provide guidance for disease prevention in the future.

Methods

A search was performed on PubMed, Web of Science, Embase, and Cochrane database up to November 9, 2022. Literature screening, information extraction and quality evaluation were performed by two researchers. The data was later combined by metaprop and metan commands in STATA 16.0.

Results

A total of 101 articles were included, including 223,221 patients. Meta-analysis showed that the overall incidence of DVT was 9.3% (95% CI: 8.2%-10.6%), and the incidence of DVT in patients with acute and chronic SCI was 10.9% (95% CI: 8.7%-13.2%) and 5.3% (95% CI: 2.2%-9.7%), respectively. The incidence of DVT decreased gradually with the accumulation of publication years and sample size. However, the annual incidence of DVT has increased since 2017. There are 24 kinds of risk factors that may contribute to the formation of DVT, involving multiple aspects of the baseline characteristics of the patient, biochemical indicators, severity of SCI, and comorbidities.

Conclusions

The incidence of DVT after SCI is high and has been gradually increasing in recent years. Moreover, there are numerous risk factors associated with DVT. Comprehensive preventive measures need to be taken as early as possible in the future.

Systematic Review Registration

www.crd.york.ac.uk/prospero, identifier CRD42022377466.

Postoperative subacute static progressive stretch does not increase the risk of distal lower limb venous thromboembolism

PURPOSE

Static progressive stretch (SPS) can be applied to treat chronic joint stiffness. However, the impacts of subacute application of SPS to the distal lower limbs, where deep vein thrombosis (DVT) is common, on venous thromboembolism remain unclear. This study aims to explore the risk of venous thromboembolism events following subacute application of SPS.

METHODS

A retrospective cohort study was conducted on patients diagnosed with DVT following a lower extremity orthopedic surgery before being transferred to the rehabilitation ward from May 2017 to May 2022. Patients with unilateral lower limb comminuted para-articular fractures, transferred to rehabilitation ward for further treatment within 3 weeks after operation, followed up more than 12 weeks since initial manual physiotherapy, and diagnosed DVT by ultrasound before rehabilitation course were included in the study. Patients with polytrauma, without evidence of previous peripheral vascular disease or incompetence, had medication for thrombosis treatment or prophylaxis before the operation, detected with paralysis due to nervous system impairment, infected after operation during the regime, or with acute progression of DVT were excluded. The included patients were randomized to the standard physiotherapy and the SPS integrated groups for observation. Associated DVT and pulmonary embolism data were collected during the physiotherapy course to compare the groups. SSPS 28.0 and GraphPad Prism 9 were used for data processing. p < 0.05 was set significant difference.

RESULTS

In total of 154 patients with DVT participating in this study, 75 of them were treated with additional SPS for postoperative rehabilitation. The participants in the SPS group showed improved range of motion (12.3° ± 6.7°). However, in the SPS group, there was no difference in thrombosis volume between the start and termination (p = 0.106, p = 0.787, respectively), although difference was seen intra-therapy (p < 0.001). Contingency analysis revealed the pulmonary embolism incidence (OR = 0.703) in the SPS group compared to the mean physiotherapy.

CONCLUSION

The SPS technique is a safe and reliable option to prevent potential joint stiffness without aggravating the risk of distal DVT for postoperative patients suffering from relevant trauma.

Predictive Value for Increased Red Blood Cell Distribution Width in Unprovoked Acute Venous Thromboembolism at the Emergency Department

Acute venous thromboembolism (VTE) is a common worldwide disease admitted to emergency departments (ED), usually presenting as pulmonary embolism or lower limb deep vein thrombosis (DVT). Due to the lack of typical clinical and biomarker diagnostic features of unprovoked VTE, early identification is challenging and has direct consequences on correct treatment delay. Longitudinal, prospective, observational study. Patients admitted to ED with a suspicion of unprovoked acute VTE between October 2020 and January 2021 were included. Clinical and laboratorial variables were compared between VTE positive and negative diagnoses. Red cell distribution width (RDW) cut point was determinate through a receiver operating characteristic analysis. RDW accuracy, sensitivity, and specificity were calculated. Fifty-eight patients were analyzed. And 82.8% of suspected patients with VTE were diagnosed with an acute thrombotic event confirmed by imaging examination. In patients with VTE, RDW at admission in ED was higher than with other diagnosis, respectively, 14.3% (13.2-15.1) and 13.5% (13.0-13.8). Platelet count was the only additional characteristic that revealed difference between the 2 groups (264×109/L for VTE and 209×109/L for non-VTE). Logistic regression models showed good discriminatory values for RDW≥14%, with an area under the curve (AUC) = 0.685 (95% confidence interval, 0.535-0.834). These findings were more pronounced in isolated DVT, with a sensitivity of 76.9%, specificity 100%, and accuracy 85.7%. Our study demonstrated a significant association between an early high RDW and the diagnosis of acute unprovoked DVT. RDW ≥ 14% has an independent predictor of unprovoked VTE in adult patients.

Construction and verification of a nomogram predicting the risk of preoperative deep vein thrombosis progression after elective spine surgery

OBJECTIVE

This study aimed to construct and verify a useful nomogram that predicts the risk of preoperative deep vein thrombosis (DVT) progression after elective spine surgery.

METHODS

Data of patients were collected from 366 patients with preoperative DVT who underwent elective spine surgery at our hospital between July 2017 and May 2022. The least absolute shrinkage and selection operator method combined with multivariable logistic regression analysis were applied to select features for the preoperative DVT progression risk model. The model's capability was evaluated using the concordance index (C-index), calibration curve, and receiver operating characteristic (ROC) curve. The decision curve and bootstrapping were used to analyze the clinical value of the nomogram.

RESULT

A total of 366 DVT patients were enrolled in this study. Preoperative DVT progression after elective spine surgery was 24.04% (88 cases). Among these patients, 86 patients had thrombosis extending into a proximal vein or appearing in a different branch of the vein, either ipsilateral or contralateral, and two had a symptomatic pulmonary embolism. D-dimer, lower extremity varicosities, hyperlipidemia, lower limb paralysis, and operation time were among the predictors in the nomogram. Furthermore, the C-index of the prediction nomogram was 0.805 (95％ CI: 0.754-0.856), with an interval bootstrapping validation of 0.786 and an area under the ROC curve value of 0.800. According to the calibration curves and decision curve analysis, the nomogram could accurately predict the probability of preoperative DVT progression after elective spine surgery.

CONCLUSION

The advantages of the nomogram included the unique discrimination capability, clinical utility, and predictive accuracy, which was beneficial for clinicians to distinguish high-risk groups of DVT progression after elective spine surgery and formulate relevant prevention measures.

Pathogenesis of Two Faces of DVT: New Identity of Venous Thromboembolism as Combined Micro-Macrothrombosis via Unifying Mechanism Based on “Two-Path Unifying Theory” of Hemostasis and “Two-Activation Theory of the Endothelium”

Simple Summary

DVT is an intravascular blood clotting disorder that can be a life-threatening disease, particularly if it occurs in critically ill patients. Typically, distal DVT develops following a vascular injury associated with incidental trauma commonly involving lower extremities, which is transient and benign condition localized in the lower legs as solitary lesion. However, proximal/central DVT (i.e., venous thromboembolism) typically occurs in association with critical illnesses such as sepsis, diabetes, hypertension, cancer, autoimmune disease and others in the hospitalized patient, especially in the ICU. Recognition of different pathogenesis between distal DVT and proximal/central DVT is critically important because the prognosis is poorer in VTE. Its therapeutic approach should be different from distal DVT. The aim of this review is to identify the pathogenesis of two different types of DVT based on in vivo hemostatic mechanisms, which can explain their distinct phenotypes by clinical characteristics, laboratory data and imaging findings. An appropriate preventive measure can be put into the practice to avoid the onset of VTE. Additionally, should VTE be developed, proper and rational therapeutic regimen based on its pathogenesis can be designed for clinical trials to improve the outcome.

Abstract

Venous thrombosis includes deep venous thrombosis (DVT), venous thromboembolism (VTE), venous microthrombosis and others. Still, the pathogenesis of each venous thrombosis is not clearly established. Currently, isolated distal DVT and multiple proximal/central DVT are considered to be the same macrothrombotic disease affecting the venous system but with varying degree of clinical expression related to its localization and severity. The genesis of two phenotypes of DVT differing in clinical features and prognostic outcome can be identified by their unique hemostatic mechanisms. Two recently proposed hemostatic theories in vivo have clearly defined the character between “microthrombi” and “macrothrombus” in the vascular system. Phenotypic expression of thrombosis depends upon two major variables: (1) depth of vascular wall damage and (2) extent of the injury affecting the vascular tree system. Vascular wall injury limited to endothelial cells (ECs) in sepsis produces “disseminated” microthrombi, but intravascular injury due to trauma extending from ECs to subendothelial tissue (SET) produces “local” macrothrombus. Pathogen-induced sepsis activates the complement system leading to generalized endotheliopathy, which releases ultra large von Willebrand factor (ULVWF) multimers from ECs and promotes ULVWF path of hemostasis. In the venous system, the activated ULVWF path initiates microthrombogenesis to form platelet-ULVWF complexes, which become “microthrombi strings” that produce venous endotheliopathy-associated vascular microthrombotic disease (vEA-VMTD) and immune thrombocytopenic purpura (ITP)-like syndrome. In the arterial system, endotheliopathy produces arterial EA-VMTD (aEA-VMTD) with “life-threatening” thrombotic thrombocytopenic purpura (TTP)-like syndrome. Typically, vEA-VMTD is “silent” unless complicated by additional local venous vascular injury. A local venous vessel trauma without sepsis produces localized macrothrombosis due to activated ULVWF and tissue factor (TF) paths from damaged ECs and SET, which causes distal DVT with good prognosis. However, if a septic patient with “silent” vEA-VMTD is complicated by additional vascular injury from in-hospital vascular accesses, “venous combined micro-macrothrombosis” may develop as VTE via the unifying mechanism of the “two-path unifying theory” of hemostasis. This paradigm shifting pathogenetic difference between distal DVT and proximal/central DVT calls for a reassessment of current therapeutic approaches.

The Impact of D-Dimer on Postoperative Deep Vein Thrombosis in Patients with Thoracolumbar Fracture Caused by High-Energy Injuries

Objective

To investigate the dynamic variation of D-dimer and to evaluate the efficacy and accuracy of D-dimer level in patients with thoracolumbar fractures caused by high-energy injuries.

Methods

A total of 121 patients with thoracolumbar fractures caused by high-energy injuries were retrospectively identified and included in this study. There were 83 males and 38 females, with an average age of 48.6 ± 11.2 years. All patients were treated with either screw fixation surgery or decompression fixation surgery. The D-dimer levels were measured 1 day before surgery and on the first, third, and fifth days after surgery. The dynamic variation of D-dimer and the effects of risk factors on D-dimer levels were analysed. A receiver operating characteristic (ROC) curve analysis was performed and the appropriate D-dimer cut-off level was determined for deep vein thrombosis (DVT) screening.

Results

Due to a trough on the third day, D-dimer levels grew in an unsustainable manner following surgery (P < 0.001). Patients with the operation time >120 min (P = 0.009) and those with an American Spinal Injury Association (ASIA) score A-C (P < 0.001) had higher D-dimer levels. The area under the curve of D-dimer was the greatest on the third day. Applying stratified cut-off values did not change the sensitivity, specificity and negative predictive value in the group with an operation time >120 min, and ASIA score A-C group.

Conclusions

D-dimer levels elevated with fluctuation in patients with thoracolumbar fractures caused by high-energy injuries after surgery. Both operation time and ASIA score had an impact on D-dimer levels. Regarding DVT diagnoses, the diagnostic value of D-dimer was highest on the third day postoperatively, and stratified cut-off values by these two factors did not show better diagnostic efficacy compared with a collective one.

Isolated calf deep venous thrombosis: frequency on venous ultrasound and clinical characteristics

Background

It remains controversial whether to include calf veins in the initial ultrasound evaluation of suspected deep venous thrombosis (DVT). We sought to investigate the frequency and clinical characteristics of isolated calf DVT.

Materials and methods

In this retrospective analysis, we investigated a cohort of 596 patients (median age 69 years, 52.3% women) who had been imaged with complete lower extremity venous duplex ultrasound for suspected acute DVT. Radiology reports were analyzed for the presence and localization of DVT. Clinical information was collected from patients’ electronic charts.

Results

DVT was found in 157 patients (26.3%), of which 74 patients (47.1%) had isolated calf DVT. Isolated calf DVTs were located in the posterior tibial veins (22 patients, 29.7%), peroneal veins (41 patients, 55.4%) and muscle veins (19 patients, 25.7%). There were no differences in age or sex between patients with isolated calf DVT and patients with proximal DVT. Isolated calf DVT was more commonly associated with leg pain (52.7% vs. 33.7%, p = 0.0234) and less commonly associated with subjective leg swelling (35.1% vs. 55.4%, p = 0.0158) and objectively measured difference in leg circumference (23% vs. 39.8%, p = 0.0268). D-Dimers were significantly lower in patients with isolated lower leg DVT (median 2.3 vs. 6.8 mg/L, p < 0.0001) compared to patients with proximal DVT.

Conclusions

Isolated calf DVT represents approximately half of DVT cases and has different clinical characteristics than proximal DVT.

Diagnostic Performance of the Caprini Risk Assessment Model Combined With D-Dimer for Preoperative Deep Vein Thrombosis in Patients With Thoracolumbar Fractures Caused by High-Energy Injuries

OBJECTIVE

To assess the validity of the Caprini risk assessment model (RAM) in risk stratification for deep vein thrombosis (DVT) and to investigate the diagnostic value of Caprini score combined with D-dimer in predicting DVT.

METHODS

This study involved 429 patients with thoracolumbar fractures caused by high-energy injuries between October 2016 and November 2019. All patients were treated surgically and had a mean age of 45.3 ± 11.4 years. Patients were risk-stratified using the 2013 Caprini RAM. Mechanical and chemical prophylaxis were used for DVT. Duplex ultrasound of both lower extremities was performed before surgery.

RESULTS

Of the 429 patients, 62 (14.45%) developed DVT. The incidence of preoperative DVT was correlated with Caprini score according to risk stratification(χ² = 117.4, P < 0.001). Based on the original Caprini RAM, all the patients scored in the highest risk category (score ≥5). Further substratification showed that the majority (277 of 429, 64.57%) of the patients were in the Caprini score range 7-8 and the risk of preoperative DVT was significantly higher among patients with Caprini score >10. The area under the receiver operating characteristic curve of Caprini score and D-dimer was 0.816 and 0.769 when Caprini score >8 or D-dimer >1.81mg/L was considered the criterion of predicting the risk of DVT. When combining the 2 variables, the area under the ROC curve can increase to 0.846.

CONCLUSIONS

The Caprini RAM is an effective and reliable DVT risk stratification tool in patients with thoracolumbar fractures caused by high-energy injuries. Caprini score >8 or D-dimer >1.81 mg/L may predict the occurrence of preoperative DVT and the Caprini score combined with D-dimer exhibit better diagnostic performance.

Risk Factors and Anticoagulation Therapy in Patients With Isolated Distal Deep Vein Thrombosis in the Early Post-operative Period After Thoracic Surgery

Background: Isolated distal deep vein thrombosis (IDDVT) accounts for ~50% of all patients diagnosed with deep venous thrombosis (DVT), but the diagnosis and optimal management of IDDVT remains unclear and controversial. The aim of this study was to explore potential risk factors and predictors of IDDVT, and to evaluate different strategies of anticoagulation therapy.

Methods: A total of 310 consecutive patients after thoracic surgery, who underwent whole-leg ultrasonography as well as routine measurements of D-dimer levels before and after surgery were evaluated. The general clinical data, anticoagulant therapy, pre- and postoperative D-dimer levels were collected. Differences between IDDVT, DVT and non-DVT groups were calculated. Logistic regression analysis was used to analyze risk factors of postoperative IDDVT.

Results: Age and postoperative D-dimer levels were significantly higher in IDDVT group than in non DVT group (p = 0.0053 and p < 0.001, respectively). Logistic regression analysis showed that postoperative D-dimer level was a significant independent predictor of IDDVT even when adjusted for age and operation method (p = 0.0003). There were no significant side effects associated with both full-dose and half-dose anticoagulation regimens. Half-dose therapy was associated with a significant decrease in the requirement for anticoagulation medications after discharge (p = 0.0002).

Conclusion: Age and D-dimer levels after surgery are strong predictors of IDDVT following thoracic surgery. Half-dose therapeutic anticoagulation has the same efficiency in preventing IDDVT progression, is not associated with any additional risks of adverse effects compared to a full-dose regimen, and may be adopted for treating IDDVT patients after thoracic surgery.

Literature review of distal deep vein thrombosis

OBJECTIVE

Although distal deep vein thrombosis (DDVT) has been more frequently diagnosed with the availability of better ultrasound imaging quality, the data on the best method to manage DDVT have been conflicting. The aim of the present review was to summarize the current and evidence-based recommendations for the diagnosis and management of DDVT and to provide a summary of the most recent societal guideline recommendations.

METHODS

A literature review of DDVT was performed. The PubMed databases were queried for articles on the epidemiology, risk factors, diagnosis, and management of DDVT.

RESULTS

The prevalence of isolated DDVT has been reported in a broad range. The reported risk factors include older age, active malignancy, a low degree of mobility, acute infection, and atrial fibrillation. With more evidence, anticoagulation therapy was found to be associated with a reduced risk of recurrent venous thromboembolism (VTE) and/or thrombus propagation compared with conservative management. However, anticoagulation was associated with an increased risk of bleeding in a number of studies. The rate of VTE recurrence ranged from 7% to 23% during a follow-up period ranging from 3 months to 8 years. The significant risk factors for VTE recurrence included cancer, older age, an unprovoked event, and inpatient status.

CONCLUSIONS

Few studies have addressed the diagnosis and management of DDVT. Further research is needed to standardize the best approach to diagnose and treat DDVT.

Performance of age-adjusted D-dimer values for predicting DVT before the knee and hip arthroplasty

Purpose

To compare the specificity and sensitivity of preoperative D-dimer and age-adjusted D-dimer value for predicting the incidence of the DVT preoperatively in total joint arthroplasty (TJA) patients.

Methods

We enrolled 406 patients finally above 50 years old. Everyone had done ultrasonography bedside, and D-dimer concentrations were collected before surgery. The D-dimer and age-adjusted D-dimer cut-off was calculated by multiple logistic regression and receiver operating curve (ROC) analyses.

Results

A total of 39 patients had found asymptomatic deep vein thrombosis (DVT) by ultrasonography. The age (odds ratio [OR] 1.067; p = 0.003) and D-dimer (OR 1.331; p = 0.025) were related to the existence of DVT. For conventional D-dimer and age-adjusted D-dimer value, the area under the curves (AUCs) were 0.685 (0.499–0.696) and 0.795 (0.611–0.881), respectively.

Conclusion

Compared to traditional D-dimer, age-adjusted D-dimer showed better performance in screening DVT, which was useful clinically.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-020-02172-w.

Calf deep vein thrombosis – clinical relevance, diagnostic approaches and therapeutic options

Summary. Isolated distal deep vein thromboses (IDDVT) represent up to 50 % of legs deep vein thromboses (DVT). However, since their natural history is to date unknown, the need to diagnose and treat them is a matter of debate. The diagnostic strategy based on the assessment of pre-test probability and D-dimer demonstrated a scarse efficiency for IDDVT. The choice between a proximal and a complete ultrasonographic approach should be guided by the clinical context, the local expertise and the patient characteristics. Randomized and observational studies have analyzed the need of therapy and compared different regimens of anticoagulation, with conflicting results. Systematic reviews and meta-analyses tend to support the usefulness of an anticoagulant treatment, even if the optimal dose and duration are not still defined. A careful stratification of the patient’s profile, taking into account risk factors for proximal extension, recurrence and bleeding should address the therapeutic approach, which must always be discussed with an adequately informed patient. Further studies aimed to clarify the natural history of IDDVT, and to assess safety and efficacy of lower intensity and shorter duration protocols are urgently needed.

Deep Venous Thrombosis in a Patient with a Moderate Pretest Probability and a Negative D-Dimer Test: A Review of the Diagnostic Algorithms

Modern diagnostic strategies of venous thromboembolism (VTE) have been developed. In this review, the diagnostic algorithms for deep-vein thrombosis (DVT) and their parameters are discussed individually in the context of reporting a case of DVT in a 43-year-old Caucasian female with a moderate pretest probability stratified by Wells’ score and a negative high quality D-dimer test. The patient was on treatment with Xarelto (rivaroxaban), 20 mg PO daily at the time of presentation. The diagnosis was verified through a complete lower limb ultrasound (US). This case highlights the diagnostic challenges and pitfalls of the current algorithms, especially those seen in a subgroup of patients such as patients with cancer, pregnancy, recurrent VTE or are on anticoagulation therapy at the time of presentation. The diagnosis of DVT is less plausible in a patient who is on anticoagulation therapy, but physicians should be aware of such a possibility. Physicians should also know in advance the numerous clinically relevant limitations of D-dimer testing before interpreting the results. Unifying the current diagnostic strategies, modifying the current Wells’ score and using the protocol of a whole-leg compression US instead of the limited US protocol are among the several cautious suggestions that have been proposed based on this review to possibly decrease the incidence of missed DVT.

Soluble platelet endothelial cell adhesion molecule 1 (sPECAM-1) improves diagnostic accuracy of D-Dimer in patients with suspected deep vein thrombosis (DVT)

D-Dimer has a high sensitivity but a low specificity for the diagnosis of deep vein thrombosis (DVT) which limits its implementation as a general screening parameter. There is a demand for additional biomarkers to improve its diagnostic accuracy. Soluble platelet endothelial cell adhesion molecule 1 (sPECAM-1) is generated at the site of venous thrombosis, thus, represents a promising biomarker. Patients with clinically suspected DVT (N = 159) were prospectively recruited and underwent manual compression ultrasonography (CCUS) to confirm or exclude DVT. The diagnostic value of D-Dimer, sPECAM-1 and the combination of both was assessed. sPECAM-1 levels were significantly higher in patients with DVT (N = 44) compared to patients without DVT (N = 115) (85.9 [76.1/98.0] ng/mL versus 68.0 [50.1/86.0] ng/mL; p < 0.001) with a diagnostic sensitivity of 100% and a specificity of 28.7% at the cut point > 50.2 ng/mL. sPECAM-1 improved the diagnostic accuracy of D-Dimer: the combination of both biomarkers yielded a ROC-AUC of 0.925 compared to 0.905 for D-Dimer alone and 0.721 for sPECAM-1 alone with a reduction of false-positive D-Dimer cases 72- > 43 (Δ =  − 31.9%). The discrimination mainly occurred in a subgroup of patients characterized by an inflammatory background (defined by c-reactive protein level > 1 mg/mL). sPECAM-1 represents a novel diagnostic biomarker for venous thrombosis. It does not qualify as a diagnostic biomarker alone but improves the diagnostic accuracy of D-Dimer in patients with suspected DVT.

Proximal and isolated distal deep vein thrombosis and Wells score accuracy in hospitalized patients

Deep vein thrombosis (DVT) is an important cause of morbidity and mortality in hospitalized patients. The Wells score for DVT pretest probability (PTP) was validated in outpatients, but its utility for inpatients is unclear. The aim of this study was to establish the prevalence of inpatient proximal and distal DVT and the Wells score performance in inpatients. A single-center cross-sectional study was conducted in a university hospital. During 183 days, all inpatients with suspected lower-extremity DVT were evaluated with the Wells score and whole-leg ultrasound. Among 634 inpatients (age 77.5 ± 13.8 years, males 39.3%), 507 (80.0%) were from medical wards and 127 (20.0%) from surgical wards. During the study period, there were 11,662 hospital admissions in the surgical/medical services. Whole-leg ultrasound detected 128 DVTs (20.2%); 51 (39.8%) were proximal and 77 (60.1%) were isolated distal DVTs. Estimated DVT prevalence in hospital setting was 1.09% (95% CI 0.93-1.31), and isolated distal DVT prevalence was 0.66% (95% CI 0.53-0.82). DVT frequency in low-, moderate-, and high-PTP groups was 9.8%, 24.3%, and 41.5%, respectively (p = 0.001). The area under the receiver operating characteristic curve for the Wells score was 0.67 ± 0.03 for all DVTs and 0.75 ± 0.04 for only proximal DVTs. A high PTP had a sensitivity of 24% (95% CI 14-37%) and a specificity of 93% (95% CI 91-95%) for proximal DVT diagnosis. In hospitalized patients, isolated distal DVT has a higher incidence than expected, and the Wells score accuracy for proximal DVT is similar to that found in outpatients.

Calf measurements screening for deep vein thrombosis in acute inpatient cancer rehabilitation

Background/Aims:

Cancer patients have a fourfold increase in the frequency of thrombosis and it is a common cause of death. The purpose of this study was to review the impact of calf measurements during initial admission to an inpatient rehabilitation unit to detect deep vein thrombosis.

Methods:

During inpatient admission to a rehabilitation unit, calf measurement assessments were performed by nursing staff. The nurses were instructed to notify clinicians for an order for a venous Doppler ultrasound if the difference between the two calves was greater than 3 cm.

Findings:

A total of 374 patients were admitted to the inpatient cancer rehabilitation unit over 12 months. Only six patients (2%) did not have their calves measured, with a 98% compliance of measurement. Only two patients (0.5%) had a difference in calf measurement and clinical exam significant to warrant a venous Doppler ultrasound. Both cases were negative for thrombosis. Venous Doppler ultrasounds were performed in 63 (17%) patients before admission to the rehabilitation unit. During the rehabilitation stay, venous Doppler ultrasounds were performed on 44 (12%) patients, with 10 (3%) patients identified with having deep vein thrombosis.

Conclusions:

This study suggests that calf measurements at admission to a rehabilitation unit were unable to detect deep vein thrombosis in this cancer population. Venous Doppler ultrasounds were ordered and identified additional patients who had deep vein thrombosis.

Highly Elevated Quantitative D-Dimer Assay Values Increase the Likelihood of Venous Thromboembolism

Objectives  In patients with suspected venous thromboembolism (VTE), the D-dimer assay is commonly utilized as part of the workup. The assay is primarily used to determine whether to proceed with radiographic imaging. We compared D-dimer levels in patients suspected of having VTE. We hypothesized that higher D-dimer values predict a higher likelihood of subsequent VTE diagnosis.

Methods  We conducted a secondary analysis of a multinational, prospective observational study of low- to intermediate-risk adult patients presenting to the emergency department with suspicion of VTE. Demographic and clinical data were collected in a structured manner. Advanced imaging including ultrasound, computed tomography (CT) pulmonary angiography, and ventilation/perfusion scanning was obtained at the discretion of the treating physicians. Imaging was evaluated by board-certified radiologists in real time. D-dimer values' bins were evaluated using a logistic regression model.

Results  We evaluated 1,752 patients for suspected deep vein thrombosis (DVT), with 191 (10.4%) DVT positive. We evaluated 1,834 patients for suspected pulmonary embolism (PE), with 108 (5.9%) PE positive. Higher D-dimer values in both groups were associated with higher likelihood of subsequent VTE diagnosis, with D-dimer values > 3,999 ng/mL in both groups having the highest incidence of VTE. More than 50% of those patients were VTE positive.

Conclusions  Increasing D-dimer values predict increased likelihood of being found VTE positive in this patient population. Among those in the highest D-dimer category, > 3,999 ng/mL, over half of patients were VTE positive. Further research could determine additional nuance in D-dimer as a tool to work up suspected VTE.

Age-adjusted D-dimer to rule out deep vein thrombosis: findings from the PALLADIO algorithm

Essentials The accuracy of the age-adjusted D-dimer in suspected venous thromboembolism is still debated. We assessed the performance of age-adjusted D-dimer combined with the PALLADIO algorithm. The age-adjusted threshold can reduce the need for imaging tests compared to the fixed cut-off. The safety of this approach should be confirmed in large management studies.

SUMMARY

Background Age-adjusted D-dimer has been proposed to increase specificity for the diagnosis of venous thromboembolism (VTE). However, the accuracy of this threshold has been recently questioned. Objectives To assess the diagnostic performance of age-adjusted D-dimer combined with clinical pretest probability (PTP) in patients with suspected deep vein thrombosis (DVT). Methods PALLADIO (NCT01412242) was a multicenter management study that validated a new diagnostic algorithm, incorporating PTP, D-dimer (using the manufacturer's cut-off) and limited or extended compression ultrasonography (CUS) in outpatients with clinically suspected DVT. Patients with unlikely PTP and negative D-dimer had DVT ruled out without further testing (group 1); patients with likely PTP or positive D-dimer underwent limited CUS (group 2); patients with likely PTP and positive D-dimer underwent extended CUS (group 3). Patients with DVT ruled out at baseline had a 3-month follow-up. In this post-hoc analysis we evaluated age-adjusted D-dimer cut-off (defined as age times 10 μg L-1 , or age times 5 μg L-1 for D-dimers with a lower manufacturer's cut-off, in patients > 50 years). Results In total, 1162 patients were enrolled. At initial visit, DVT was detected in 4.0% of patients in group 2 and 53.0% in group 3. The age-adjusted D-dimer, compared with the fixed cut-off, resulted in 5.1% (95% CI, 4.0-6.5%) reduction of CUS. The incidence of symptomatic VTE during follow-up was: 0.24% (95% CI, 0.04-1.37) in group 1; 1.12% (95% CI, 0.44-2.85) in group 2; and 1.89% (95% CI, 0.64-5.40) in group 3. Conclusions The PALLADIO algorithm using age-adjusted D-dimer slightly decreased the number of required imaging tests, but this approach should be confirmed in large management studies.

Venous Thromboembolism in Gynecological Malignancy

Objective

Venous thromboembolism (VTE) is a recognized complication of gynecological malignancy and represents a leading cause of morbidity and mortality in these patients. The review aimed to discuss the incidence, risk factors, and clinical presentation of VTE before examining the literature on the diagnosis, prevention, and management in the context of uterine, cervical, ovarian, and vulval cancers.

Methods/Materials

A literature search was performed using Ovid Medline and Embase with the following words: “gynecological malignancy,” “pelvic tumor,” “venous thromboembolism,” “deep vein thrombosis” and “pulmonary embolism.”

Results

The incidence of VTE in patients with gynecological malignancy ranged between 3% and 25% and was affected by several patient and tumor factors. Duplex ultrasonography is currently the first-line imaging modality for deep venous thrombosis with sensitivity and specificity of up to 95% and 100%, respectively. Low-molecular-weight heparin is currently the VTE prophylaxis and treatment of choice for patients with gynecological malignancy, although warfarin and unfractionated heparin play a role in selected circumstances. The relatively new direct oral anticoagulants including factor Xa inhibitors and direct thrombin inhibitors are increasingly being used, although further evaluations are required, particularly in cancer patients. Catheter-directed thrombolysis and percutaneous mechanical and surgical thrombectomy may have a role in treating patients with severe symptomatic iliocaval or iliofemoral deep venous thrombosis. Overall, VTE is a poor prognosis marker in patients with gynecological malignancy.

Conclusions

Gynecological malignancy–associated VTE is associated with significant morbidity, contributing to a large number of life years lost. Although promising new therapies are emerging, a 2-pronged approach is required to simultaneously target cancer-specific management and predict early on those who are likely to be affected. In the meantime, clinicians should continue to combine current guidelines with a multidisciplinary team approach to ensure that these complex patients receive the best evidence-based and compassionate care.

New biomarkers and imaging approaches for the diagnosis of deep venous thrombosis

PURPOSE OF REVIEW

Symptoms suggestive of deep vein thrombosis (DVT) are extremely common in clinical practice, but unfortunately nonspecific. In both ambulatory and inpatient settings, clinicians are often tasked with evaluating these concerns. Here, we review the most recent advances in biomarkers and imaging to diagnose lower extremity DVT.

RECENT FINDINGS

The modified Wells score remains the most supported clinical decision rule for risk stratifying patients. In uncomplicated patients, the D-dimer can be utilized with risk stratification to reasonably exclude lower extremity DVT in some patients. Although numerous biomarkers have been explored, soluble P-selectin has the most promise as a novel marker for DVT. Imaging will be required for many patients and ultrasound is the primary modality. Nuclear medicine techniques are under development, and computed tomography (CT) and magnetic resonance venography are reasonable alternatives in select patients.

SUMMARY

D-dimer is the only clinically applied biomarker for DVT diagnosis, with soluble P-selectin a promising novel biomarker. Recent studies have identified several other potential biomarkers. Ultrasound remains the imaging modality of choice, but CT, MRI, or nuclear medicine tests can be considered in select scenarios.

Diagnosis of deep-vein thrombosis

The diagnostic approach to suspected symptomatic deep-vein thrombosis of the lower extremities is usually based on non-invasive methods, including the estimation of clinical probability, the measurement of D-dimer levels, and ultrasonography. The present review discusses the evidence available from the literature about the management of the first episode of suspected deep-vein-thrombosis.

Age-related diagnostic value of D-dimer testing and the role of inflammation in patients with suspected deep vein thrombosis

Previous reports have investigated the impact of age on D-Dimer testing in elderly individuals with suspected deep vein thrombosis (DVT), but data on the age-related diagnostic value of D-dimer in a sample covering a broad age range are limited. The present study determined age-specifically the diagnostic accuracy of D-dimer and compared it to C-reactive protein (CRP), a marker of inflammation, in 500 patients with suspected DVT from the VTEval project (NCT02156401). Sensitivity of D-dimer was lower in patients < 60 years in comparison to patients ≥ 60 years (∆-16.8%), whereas specificity was 27.9% higher. Lowest levels of sensitivity were detected for female sex, unprovoked DVT, low thrombotic burden, and distal DVT. A fixed D-dimer threshold of 0.25 mg/L FEU resulted in elevated sensitivity for patients < 60 with a reduction of false negatives by 40.0% for proximal DVT and by 50.0% for distal DVT. In patients < 60 years, D-dimer and CRP demonstrated comparable diagnostic performance for both proximal and distal DVT (p > 0.05). In conclusion, these data outline a clinically-relevant limitation of D-dimer testing among younger patients with suspected DVT indicating a necessity for age-adapted cut-off values. Further research is required to decrypt the role of inflammation in the pathophysiology and diagnosis of venous thrombosis.

Treatment of Isolated Below the Knee Deep Vein Thrombosis

The natural history of isolated distal deep-vein thrombosis (IDDVT) is still uncertain, as well as the real clinical risks associated with the disease and the need for its diagnosis and treatment. While more and more IDDVTs are diagnosed in everyday clinical practice, their appropriate therapeutic management is, unfortunately, far from straightforward, and different recommendations on how patients with diagnosed IDDVT should be treated are present between expert professionals and even among international guidelines. The present article aims at briefly reviewing the issue of IDDVT therapy in general, particularly focusing on the different approaches to the treatment of the disease that have been suggested by recent guidelines, those that are currently adopted in clinical practice, and necessary future directions.

A systematic review of clinical prediction scores for deep vein thrombosis

Objective Diagnosis of deep vein thrombosis remains a challenging problem. Various clinical prediction rules have been developed in order to improve diagnosis and decision making in relation to deep vein thrombosis. The purpose of this review is to summarise the available clinical scores and describe their applicability and limitations. Methods A systematic search of PubMed, MEDLINE and EMBASE databases was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance using the keywords: clinical score, clinical prediction rule, risk assessment, clinical probability, pretest probability, diagnostic score and medical Subject Heading terms: 'Venous Thromboembolism/diagnosis' OR 'Venous Thrombosis/diagnosis'. Both development and validation studies were eligible for inclusion. Results The search strategy returned a total of 2036 articles, of which 102 articles met a priori criteria for inclusion. Eight different diagnostic scores were identified. The development of these scores differs in respect of the population included (hospital inpatients, hospital outpatients or primary care patients), the exclusion criteria, the inclusion of distal deep vein thrombosis and the use of D-dimer. The reliability and applicability of the scores in the context of specific subgroups (inpatients, cancer patients, elderly patients and those with recurrent deep vein thrombosis) remains controversial. Conclusion Detailed knowledge of the development of the various clinical prediction scores for deep vein thrombosis is essential in understanding the power, generalisability and limitations of these clinical tools.

Management of distal deep vein thrombosis

Isolated distal deep vein thrombosis (DVT), also known as calf DVT, represents up to 50% of all lower limb DVT in ultrasound series and is therefore a frequent medical condition. Unlike proximal DVT and pulmonary embolism (PE), which have been extensively studied and for which management is well standardized, much less is known on the optimal management of isolated calf DVT. Recent data arising from registries and non-randomized studies suggest that most distal DVTs do not extend to the proximal veins and have an uneventful follow-up when left untreated. This data had some impact on the international recommendations which recently stated that ultrasound surveillance instead of systematic therapeutic anticoagulation might be an option for selected low-risk patients. However, robust data arising from randomized studies are scarce. Indeed, only five randomized trials assessing the need for anticoagulation for calf DVT have been published. Many of these trials had an open-label design and were affected by methodological limitations. The only randomized placebo-controlled trial included low-risk patients (outpatients without cancer or previous venous thromboembolic events (VTE)) and was hampered by a limited statistical power. Nevertheless, data from this trial tend to confirm that the use of therapeutic anticoagulation in low-risk patients with symptomatic calf DVT is not superior to placebo in reducing VTE, but is associated with a significantly higher risk of bleeding. Further randomized studies are needed to define the best therapy for high-risk patients (inpatients, patients with active cancer or previous VTE), and the optimal dose and duration of treatment.

Elevated d-Dimer Is Not Predictive of Symptomatic Deep Venous Thrombosis After Total Joint Arthroplasty

BACKGROUND

Serum d-dimer is a common screening test for symptomatic deep venous thrombosis (DVT) after total joint arthroplasty. This study characterized the longitudinal resolution of d-dimer measurements after total hip and knee arthroplasty (THA/TKA) over a 6-week period. The authors hypothesized that serum d-dimer would not return to baseline or be below the institutional threshold for a positive test at 6 weeks after uncomplicated total joint arthroplasty, suggesting that quantitative d-dimer has limited clinical utility for postoperative DVT screening.

METHODS

An institutional review board-approved retrospective cohort study was conducted with consecutive patients between January 2013 and June 2015. A total of 177 adult patients aged 40-88 years who underwent a primary hip or knee arthroplasty with a Charlson Comorbidity Index <3 were included in the study. Serum d-dimer was measured at preoperative, perioperative, and postoperative 2- and 6-week time points.

RESULTS

d-dimer measurements peaked 2 weeks postoperatively for both TKA and THA. At the 6-week time point, the peak serum d-dimer measurement resolved by 54.3% and 76.6% for TKA and THA, respectively. At 6 weeks after operation, 92% of THA patient and 100% of TKA patients had serum d-dimer measurements higher than the institutional threshold (0.40 μg/mL) for a "positive" quantitative test. No symptomatic DVTs were reported for the THA and TKA cohorts during the study period.

CONCLUSION

The results suggest that serum d-dimer is an ineffective screening test for the diagnosis of symptomatic DVT in the acute postoperative period. The authors propose that extravascular fibrinolysis, a process essential for wound healing, has a crucial role in the prolonged elevation of serum d-dimer in the postoperative period.

Evaluation of D-dimer and lactate dehydrogenase plasma levels in patients with relapsed acute leukemia

Despite the outstanding advances made over the past decade regarding our knowledge of acute leukemia (AL), relapsed AL remains to be associated with a dismal prognosis. A better understanding of AL relapse and monitoring of the D-dimer and lactate dehydrogenase (LDH) plasma levels following chemotherapy may aid clinicians in determining whether relapse may occur in the subsequent phases of the disease. The present study evaluated D-dimer and LDH levels in 204 patients with relapsed AL. Data were collected at the initial onset of AL, at complete remission (CR) and in patients with relapsed AL. D-dimer plasma levels were significantly increased in patients with initial AL and in patients with relapsed AL (P=0.005 and P=0.007, respectively) but not in those with CR. LDH levels were significantly increased in AL patients at the initial onset of disease and at relapse compared with patients achieving CR, irrespective of cell type. Plasma prothrombin time, activated partial thromboplastin time and fibrinogen levels were not significantly different across patients (with the exception of acute promyelocytic leukemia patients) at the initial onset, relapsed AL or CR. Routine hematological parameters (white blood cell count, hemoglobin, platelet count) were significantly different at the initial onset of AL (P=0.002, P<0.001 and P=0.001, respectively) and during relapsed AL (P=0.009, P=0.003 and P<0.001, respectively) compared with patients achieving CR, suggesting an association between D-dimer, LDH and relapsed AL. These results also indicate that determination of D-dimer and LDH levels may be useful for predicting the probability of relapse during chemotherapy, but should also be combined with routine hematological parameters.

Emergency Department Management of Suspected Calf-Vein Deep Venous Thrombosis: A Diagnostic Algorithm

Introduction

Unilateral leg swelling with suspicion of deep venous thrombosis (DVT) is a common emergency department (ED) presentation. Proximal DVT (thrombus in the popliteal or femoral veins) can usually be diagnosed and treated at the initial ED encounter. When proximal DVT has been ruled out, isolated calf-vein deep venous thrombosis (IC-DVT) often remains a consideration. The current standard for the diagnosis of IC-DVT is whole-leg vascular duplex ultrasonography (WLUS), a test that is unavailable in many hospitals outside normal business hours. When WLUS is not available from the ED, recommendations for managing suspected IC-DVT vary. The objectives of the study is to use current evidence and recommendations to (1) propose a diagnostic algorithm for IC-DVT when definitive testing (WLUS) is unavailable; and (2) summarize the controversy surrounding IC-DVT treatment.

Discussion

The Figure combines D-dimer testing with serial CUS or a single deferred FLUS for the diagnosis of IC-DVT. Such an algorithm has the potential to safely direct the management of suspected IC-DVT when definitive testing is unavailable. Whether or not to treat diagnosed IC-DVT remains widely debated and awaiting further evidence.

Conclusion

When IC-DVT is not ruled out in the ED, the suggested algorithm, although not prospectively validated by a controlled study, offers an approach to diagnosis that is consistent with current data and recommendations. When IC-DVT is diagnosed, current references suggest that a decision between anticoagulation and continued follow-up outpatient testing can be based on shared decision-making. The risks of proximal progression and life-threatening embolization should be balanced against the generally more benign natural history of such thrombi, and an individual patient’s risk factors for both thrombus propagation and complications of anticoagulation.

Sparing ultrasound in emergency department patients with suspected deep vein thrombosis by using clinical scores and D-dimer testing

PURPOSE

To evaluate compliance with a management strategy for use in emergency department (ED) patients with suspected deep vein thrombosis (DVT) based on Wells score (WS), D-dimer concentrations, and sonographic (US) examinations.

METHODS

Retrospective and prospective data on risk factors, physical examination findings, D-dimer concentrations, and US results were collected and reviewed. The prevalence of DVT for each WS category and D-dimer level was calculated.

RESULTS

In the retrospective part of the study, 475 consecutive patients were included. Patients' risk for DVT was scored as high (n = 129 [27.2%]), moderate (n = 95 [20%]), or low (n = 251 [52.8%]). D-Dimer test results were available for 34 (7.2%) of the patients. DVT was diagnosed in 105 (22.1%) patients: 99 (76.7%) at high, 4 (4.2%) at moderate, and 2 (0.8%) at low risk. The mean D-dimer concentration was 3,071.7 ng/ml in patients with DVT. In the prospective part of the study, 50 patients were enrolled. Their risk levels for DVT were scored as high (n = 23 [46%]), moderate (n = 7 [14%]), and low (n = 20 [40%]). D-Dimer testing was performed in all patients. The mean D-dimer concentration was 2,966.9 ng/ml in patients with DVT. DVT was diagnosed in 13 (26%) of these 50 patients: 12 (52.2%) at high and 1 (14.3%) at moderate risk for DVT. No patients in the low-risk group and with normal D-dimer concentrations had DVT.

CONCLUSIONS

We identified significant correlation between WS, D-dimer concentration, and diagnosis of DVT on US examination. DVT can be excluded with certainty in patients admitted to the ED with a low-risk score for DVT and a negative D-dimer concentration, thus avoiding the need for performing US examinations. A low level of compliance with this management strategy was found in our ED.

Widely Used Types and Clinical Applications of D-Dimer Assay

D-dimers are formed by the breakdown of fibrinogen and fibrin during fibrinolysis. D-dimer analysis is critical for the diagnosis of deep vein thrombosis, pulmonary embolism, and disseminated intravascular coagulation. Modern assays for D-dimer are monoclonal antibody based. The enzyme-linked immunosorbent assay (ELISA) is the reference method for D-dimer analysis in the central clinical laboratory, but is time consuming to perform. Recently, a number of rapid, point-of-care D-dimer assays have been developed for acute care settings that utilize a variety of methodologies. In view of the diversity of D-dimer assays used in central laboratory and point-of-care settings, several caveats must be taken to assure the proper interpretation and clinical application of the results. These include consideration of preanalytical variables and interfering substances, as well as patient drug therapy and underlying disease. D-dimer assays should also be validated in clinical studies, have established cut-off values, and reported according to the reagent manufacturers recommendations.

Rationale and design of three observational, prospective cohort studies including biobanking to evaluate and improve diagnostics, management strategies and risk stratification in venous thromboembolism: the VTEval Project

INTRODUCTION

Venous thromboembolism (VTE) with its two manifestations deep vein thrombosis (DVT) and pulmonary embolism (PE) is a major public health problem. The VTEval Project aims to investigate numerous research questions on diagnosis, clinical management, treatment and prognosis of VTE, which have remained uncertain to date.

METHODS AND ANALYSIS

The VTEval Project consists of three observational, prospective cohort studies on VTE comprising cohorts of individuals with a clinical suspicion of acute PE (with or without DVT), with a clinical suspicion of acute DVT (without symptomatic PE) and with an incidental diagnosis of VTE (PE or DVT). The VTEval Project expects to enrol a total of approximately 2000 individuals with subsequent active and passive follow-up investigations over a time period of 5 years per participant. Time points for active follow-up investigations are at months 3, 6, 12, 24 and 36 after diagnosis (depending on the disease cohort); passive follow-up investigations via registry offices and the cancer registry are performed 48 and 60 months after diagnosis for all participants. Primary short-term outcome is defined by overall mortality (PE-related death and all other causes of death), primary long-term outcome by symptomatic VTE (PE-related death, recurrence of non-fatal PE or DVT). The VTEval Project includes three 'all-comer' studies and involves the standardised acquisition of high-quality data, covering the systematic assessment of VTE including symptoms, risk profile, psychosocial, environmental and lifestyle factors as well as clinical and subclinical disease, and it builds up a large state-of-the-art biorepository containing various materials from serial blood samplings.

ETHICS AND DISSEMINATION

The VTEval Project has been approved by the local data safety commissioner and the responsible ethics committee (reference no. 837.320.12 (8421-F)). Trial results will be published in peer-reviewed journals and presented at national and international scientific meetings.

TRIAL REGISTRATION NUMBER

NCT02156401.

American College of Foot and Ankle Surgeons' clinical consensus statement: risk, prevention, and diagnosis of venous thromboembolism disease in foot and ankle surgery and injuries requiring immobilization

The purpose of this document is to provide guidance for physicians regarding the risk, prevention, and diagnosis of venous thromboembolism disease after foot and ankle surgery and while caring for lower extremity injuries that require ankle immobilization. A panel composed of all authors of this document reviewed the published evidence and, through a series of meetings, reached consensus regarding the viewpoints contained herein. We conclude that routine chemical prophylaxis is not warranted; rather, patients should be stratified and have a prevention plan tailored to their individual risk level. An effective venous thromboembolism prevention program is typically multimodal and focuses on addressing any modifiable risk factors, use of mechanical prophylaxis, early mobilization, and careful consideration of the use of chemical prophylaxis. The final decision regarding use and method(s) of prophylaxis adopted should be agreed upon by both the clinician and patient after a discussion of the potential benefits and harms as they relate to the individual. This should take place preferably during the preoperative visit or in the immediate post-injury setting, and it may need to be revisited during the course of care if the patient's risk level changes. Prompt recognition of the signs and symptoms of deep venous thrombosis following surgery or injury is important. Patients suspected of deep venous thrombosis should receive further work-up with either a D-dimer test or duplex venous ultrasound of the symptomatic leg, depending on their pretest probability for the disease. The latter can be determined using a validated clinical decision-making tool (e.g., Well's criteria).

D-dimer for the diagnosis of upper extremity deep and superficial venous thrombosis

BACKGROUND

D-dimer role is well established in the diagnostic work-up for lower limb deep vein thrombosis (DVT), however it has not been formally tested for clinically suspected upper extremity DVT and/or superficial vein thrombosis (SVT).

AIM

To ascertain D-dimer diagnostic accuracy for upper extremity DVT and/or SVT.

STUDY DESIGN

We performed a single centre management study in outpatients referred by emergency or primary care physicians for clinically suspected upper extremity DVT. All patients underwent D-dimer testing (cut-off value: ≤500 ng/mL), and a B-mode and color Doppler ultrasonography examination. In case of either technical problems or anatomical barriers, ultrasonography was repeated after 5-7 days. All patients were followed up for three months for the occurrence of symptomatic DVT and/or SVT and/or pulmonary embolism.

RESULTS

We enrolled 239 patients (F: 63.6%; mean±SD age: 58.3±16.8). At the initial diagnostic work-up, DVT was detected in 24 (10%) patients while SVT in 35 (14.6%) patients. During follow-up, one upper extremity DVT was found. D-dimer levels were higher in patients with DVT than in those without. Sensitivity and specificity of D-dimer for DVT were 92% (95%CI: 73-99%) and 60% (95%CI: 52-67%) respectively, with a negative predictive value of 98% (95%CI: 93-100%), whereas for SVT they were 77% (95%CI: 59-89%) and 60% (95%CI: 52-67%) respectively, with a negative predictive value of 93% (95%CI: 86-97%).

CONCLUSIONS

D-dimer has a negative predictive value ≥93% for excluding DVT in symptomatic outpatients and it can be a useful test in the diagnostic work-up of suspected upper extremity DVT.

Two years outcome of isolated distal deep vein thrombosis

BACKGROUND

Isolated distal deep vein thrombosis (IDDVT) is frequently found in symptomatic outpatients, but its long term outcome is still uncertain.

AIMS

To assess IDDVT long term outcome and the impact of IDDVT characteristics on outcome.

METHODS

In a prospective, single center study we enrolled symptomatic outpatients in whom IDDVT was detected by whole-leg compression ultrasonography. Patients with provoked IDDVT were treated with low molecular weight heparins (LMWH) for 30 days while those with unprovoked IDDVT received with vitamin K antagonists (VKA) for three months. The primary end-point was the rate of the composite of pulmonary embolism (PE), proximal deep vein thrombosis (DVT), and IDDVT recurrence/extension during 24 month follow-up.

RESULTS

90 patients (age 61 ± 18, male 48.9%) were enrolled. Risk factors for thrombosis were reduced mobility (34.4%), obesity (25.3%), surgery (15.6%), and previous DVT (15.6%) and cancer in 8 patients (8.9%). Eighty-eight patients were treated (56 with LMWH and 32 with VKA). During follow-up (median 24 ± 2 months), 17 events were recorded, which included 3 PE (two in cancer patients), 4 proximal DVTs (one in cancer patient) and 10 IDDVT. Male sex (HR 4.73 CI95%: 1.55-14.5; p=0.006) and cancer (HR 5.47 CI95%: 1.76-17.6; p=0.003) were associated with a higher risk of complications, whereas IDDVT anatomical characteristics, anticoagulant therapy type, and provoked IDDVT were not.

CONCLUSIONS

The risk of recurrent venous thromboembolism after IDDVT may be relevant in male patients or in patients with active cancer. Larger studies are needed to address this issue.

How I treat isolated distal deep vein thrombosis (IDDVT)

Thromboses limited to infrapopliteal leg deep veins (isolated distal deep vein thrombosis [IDDVT]) are frequently diagnosed in subjects with suspected pulmonary embolism or DVT and account for one-fourth to one-half of all diagnosed leg DVTs. Despite their frequency, the natural history of IDDVTs and their real risk of thromboembolic complications are still uncertain because of the scarcity of prospective, blind, nonintervention studies. Therefore it is still debated whether they warrant diagnosis and treatment. Diagnosis is based on ultrasonographic examination, which is more operator dependent and less sensitive in distal than in proximal veins. The available data seem to support the view that most IDDVTs are self-limiting and inconsequential for patients, though in some cases they can be associated with complications and warrant diagnosis and treatment. The available guidelines for treatment of IDDVTs give different indications ranging from serial imaging of the deep veins for 2 weeks to detect and treat only in case of proximal extension, to giving oral anticoagulation in all IDDVT patients for 3 months. I review this issue, focusing on possible and suggested treatments in symptomatic IDDVT patients, and describe our current therapeutic approach to these patients.

Economic evaluation of different screening alternatives for patients with clinically suspected acute deep vein thrombosis

INTRODUCTION

We examined the cost-effectiveness of the three different D-dimer measurements in the screening of DVT in models with and without calculation of pre-test probability (PTP) score. Moreover, we calculated the minimal cost in DVT detection.

MATERIAL AND METHODS

In the group of 192 patients with clinically suspected acute DVT, we examined the three different D-dimer measurements (Innovance D-dimer, Hemosil D-dimer HS and Vidas D-dimer Exclusion II) in combination with and without PTP assessment.

RESULTS

The diagnostic alternative employing Vidas D-dimer Exclusion II assay without and with PTP calculation gave lower incremental cost-effectiveness ratio (ICER) than the alternative employing Hemosil D-dimer HS assay (0.187 Euros vs. 0.998 Euros per one additional DVT positive patient selected for CUS in model without PTP assessment and 0.450 vs. 0.753 Euros per one DVT positive patient selected for CUS in model with PTP assessment). According to sensitivity analysis, the Hemosil D-dimer HS assay was the most cost effective alternative when one patient was admitted to the vascular ambulance per day. Vidas D-dimer Exclusion II assay was the most cost effective alternative when more than one patient were admitted to the vascular ambulance per day. Cost minimisation analysis indicated that selection of patients according to PTP score followed by D-dimer analysis decreases the cost of DVT diagnosis.

CONCLUSIONS

ICER analysis enables laboratories to choose optimal laboratory tests according to number of patients admitted to laboratory. Results support the feasibility of using PTP scoring and D-dimer measurement before CUS examination in DVT screening.