Clinical relevance of distal deep vein thrombosis

Comparison of clinical outcomes among patients with isolated axial vs muscular calf vein thrombosis: A systematic review and meta-analysis

OBJECTIVE

Thrombi in the axial calf veins have quite different anatomical and physiological characteristics from that in the muscular calf veins, but their treatment was usually addressed in the same manner. We performed a meta-analysis of randomized and cohort studies to compare clinical outcomes among patients with isolated axial vs muscular calf deep vein thrombosis (DVT).

METHODS

Recurrent venous thromboembolism (VTE) was selected as the primary outcome. Resolution, proximal propagation of calf DVT, pulmonary embolism (PE), major bleeds, and clinically relevant non-major bleeds were separately analyzed as secondary outcomes. Data were pooled and compared with risk ratio (RR) and 95% confidence interval (CI).

RESULTS

Thirteen studies, consisting of 4889 patients, met the inclusion criteria and were included for analysis. A greater rate of recurrent VTE (FE model: RR, 1.23; 95% CI, 1.00-1.53; I2 = 29%), resolution (FE model: RR, 1.32; 95% CI, 1.01-1.72; I2 = 31%), proximal propagation (FE model: RR, 1.63; 95% CI, 1.10-2.41; I2 = 40%), and PE (FE model: RR, 2.79; 95% CI, 1.31-5.95; I2 = 0%) in the axial group compared with the muscular group. There was no difference in the pooled estimates for major bleeds (FE model: RR, 1.09; 95% CI, 0.61-1.95; I2 = 0%), and clinically relevant non-major bleeds (FE model: RR, 1.80; 95% CI, 0.93-3.48) in the axial and muscular arms.

CONCLUSIONS

Patients with calf DVT limited to muscular veins might have a lower rate of recurrent VTE, resolution, proximal propagation, and PE vs those with axial calf vein involvement and exhibited similar safety outcomes.

Elderly hip fracture patients with isolated calf muscle vein thrombosis are more likely to have suffered an intertrochanteric fracture and be hypertensive

PURPOSE

This study aimed to characterize the preoperative deep venous thrombosis (DVT) of lower extremity by locations and evaluate the diagnostic ability of plasma D-dimer level in elderly patients with hip fracture.

METHOD

This retrospective study reviewed the elderly patients presenting with a hip fracture definitely undergoing surgical treatment and identified those who had preoperative DVT. Data on demographics, lifestyle habits, comorbidities and laboratory indexes were extracted and collected. Four groups were divided by presence and locations of thrombi: non-DVT (controls), isolated calf muscle vein thrombosis (CMVT), deep calf vein thrombosis (DCVT) and proximal DVT group. The comparisons were conducted between either DVT group or the non-DVT group. Receiver operating characteristic (ROC) curve and the area under the curve (AUC) were used for determining the diagnostic ability of D-dimer for each group.

RESULTS

Among 951 eligible patients included, 298 (31.3%) were found have preoperative DVT. Compared to non-DVT group, patients with CMVT had significantly lower albumin and hemoglobin concentration, more likely an intertrochanteric fracture and a higher prevalence of hypertension (P = 0.001, 0.006, 0.002 and 0.024, respectively); DCVT group was not observed to be significantly different in terms of any variables (all P > 0.05); and proximal DVT group had older age and more patients ≥ 80 years, lower albumin and hemoglobin concentration, higher prevalence of hypertension, more likely an intertrochanteric fracture, extended time from injury to imaging examination and higher age-adjusted Charlson comorbidity index (ACCI) (all P < 0.05). D-dimer demonstrated nonsignificant diagnostic ability for CMVT and DCVT, and a significant but poor ability for proximal DVT (AUC, 0.621; 95% CI 0.542-0.710; P = 0.011).

CONCLUSION

Varying characteristics were found among preoperative DVT stratified by locations after elderly hip fractures, and D-dimer level demonstrated no or poor diagnostic ability for DVTs by locations. Level of evidence level III, diagnostic. Trial registration statement Not applicable.

Association between higher systemic immune inflammation index (SII) and deep vein thrombosis (DVT) in patients with aneurysmal subarachnoid hemorrhage (aSAH) after endovascular treatment

Inflammation contributes to deep vein thrombosis (DVT) formation in patients with aSAH after endovascular treatment. The relationship between systemic immune-inflammatory index (SII) as an inflammatory marker and DVT formation remains unclear. Thus, this study aims to evaluate the association between SII and aSAH-associated DVT following endovascular treatment. We enrolled 562 consecutive patients with aSAH after endovascular treatment at three centers from January 2019 to September 2021. The endovascular treatments included simple coil embolization and stent-assisted coil embolization. Deep venous thrombosis (DVT) was assessed by Color Doppler ultrasonography (CDUS). Multivariate logistic regression analysis was used to establish the model. We assessed the association of the SII, neutrophil-to-lymphocyte ratio (NLR), the systemic inflammatory response index (SIRI), platelet-lymphocyte ratio (PLR), and DVT by using restricted cubic spline (RCS). ASAH-associated DVT was found in 136 (24.20%) patients. Based on the multiple logistic regression analysis, the correlation was found between aSAH-associated DVT and elevated SII (fourth quartile) (adjusted odds ratio = 8.20 [95% confidence interval, 3.76-17.92]; p < 0.001 [p for trend < 0.001]), elevated NLR (fourth quartile) (adjusted odds ratio = 6.94 [95% confidence interval, 3.24-14.89]; p < 0.001 [p for trend < 0.001]), elevated SIRI (fourth quartile) (adjusted odds ratio = 4.82 [95% confidence interval, 2.36-9.84]; p < 0.001 [p for trend < 0.001]), and elevated PLR (fourth quartile) (adjusted odds ratio = 5.49 [95% confidence interval, 2.61-11.57]; p < 0.001 [p for trend < 0.001]). The increased SII was correlated with the formation of aSAH-associated DVT after endovascular treatment.

High rate of false-positive postoperative venous thromboembolism identified using hospital ICD-10 coding

The Health Roundtable, a national benchmarking body, identified our institution as an outlier with a high number of postoperative venous thromboembolism (VTE) events. We performed a retrospective study to determine the accuracy of hospital coding for the incidence and severity of postoperative VTE. Of 232 patients identified from ICD-10 coding, 52 (22.4%) were incorrectly coded. Approximately one third (n = 68) of all VTE were asymptomatic, diagnosed incidentally. Thus, coding data are inherently flawed with inaccuracy and overrepresent the true number of VTE events, with a substantial proportion of limited clinical relevance.

Characteristics and Treatment Strategy of Isolated Calf Deep Venous Thrombosis after Fractures: A Review of Recent Literature

Isolated calf deep venous thrombosis (ICDVT) includes thrombosis located at the far end of the popliteal vein, such as the anterior tibial vein, posterior tibial vein, fibular vein, and intramuscular vein of the soleus and gastrocnemius. This type of thrombosis has the highest incidence, accounting for approximately half of all deep vein thrombosis (DVT) cases; however, there is no consistent recommendation for ICDVT treatment across countries, and there is also no optimal management strategy. In recent years, increasing evidence has shown that ICDVT can develop into proximal DVT, even causing pulmonary embolism (PE). Therefore, some experts suggest anticoagulant therapy for this type of DVT, while others hold an opposing attitude. Therefore, the treatment strategy for this type of DVT has become a hot and difficult research topic. The purpose of this review is to summarize the characteristics of ICDVT and the effects of different treatment strategies by analyzing recent and important classical works in the literature in an attempt to provide recommendations for the treatment of this most common type of DVT in orthopaedic clinics.

Two Weeks of Low Molecular Weight Heparin for Isolated Symptomatic Distal Vein Thrombosis (TWISTER study)

BACKGROUND

Treatment of low-risk patients with isolated symptomatic distal deep vein thrombi (IDDVT) is uncertain.

OBJECTIVE

assess whether two weeks of therapeutic anticoagulation is efficacious/safe for IDDVT.

PRIMARY OUTCOME

symptomatic three-month venous thromboembolism (VTE) incidence in the two-week anticoagulation group. Secondary outcomes included post-thrombotic syndrome (PTS) and bleeding.

METHODS

Prospective multicentre cohort study. Consecutive low-risk IDDVT patients enrolled within 72 h of diagnosis and treated with therapeutic dose enoxaparin or rivaroxaban. At two weeks, patients had repeat complete whole leg compression ultrasound (CUS)/clinical review. If resolution of leg symptoms AND no radiological evidence of thrombus extension, anticoagulation was stopped. If ongoing symptoms and/or radiographic extension within distal veins, anticoagulation was continued for four more weeks. Patients with extension into the popliteal vein on two-week ultrasound were treated off-study. Patients were reviewed at three and six months.

FINDINGS/INTERPRETATION

241 eligible patients received ≥2 weeks anticoagulation. 167/241 (69%) were assigned to the 2-week anticoagulation group; 71/241 (30%) to the six-week anticoagulation group; 3/241 patients (1%) had extension into the popliteal vein on two-week CUS. Two patients in the two-week anticoagulation group had symptomatic IDDVT recurrence in ≤3 months; VTE recurrence 2/156; 1.3%(95% CI 0.05-4.85%). 69% of patients had complete resolution of symptoms within two weeks. Six-month PTS rates were 8/184, 4.4%(95% CI 2.1-8.5%). No major bleeding was reported. Our findings suggest it's safe/efficacious to stop therapeutic anticoagulation at two weeks in low-risk IDDVT patients with resolution of symptoms/no extension on ultrasound. This could replace 6-12 weeks of anticoagulation for ambulatory, low-risk IDDVT patients.

TRIAL REGISTRATION

ClinicalTrials.govNCT01252420.

Calf deep vein thrombosis: frequency, therapeutic management, early outcomes and all-causes mortality in a cohort of hospitalized patients

BACKGROUND

Isolated distal deep vein thromboses (IDDVT) are frequent; however, their optimal management is still controversial.

METHODS

We performed a retrospective study on inpatients undergoing ultrasound for suspected deep vein thrombosis (DVT) or with a particular risk profile, during 2016. This study aimed to assess the frequency of proximal deep vein thromboses (PDVT) and IDDVT; to evaluate therapeutic management and identify variables associated with early outcomes and mortality among IDDVT patients; to compare all-causes mortality between subjects with PDVT and IDDVT.

RESULTS

Among 21594 patients hospitalized in the study period 251 IDDVT and 149 PDVT were diagnosed; the frequency was 1.2% and 0.7% respectively. 19% of IDDVT patients died compared to 25.5% of PDVT subjects (OR=0.72; 95% CI=0.44-1.17; P=0.19). In IDDVT patients, age ≥80, cancer and intracranial bleeding increased the risk of death (OR=2; 95% CI=1.07-3.75, P=0.001; OR=8.47; 95% CI=3.28-21.88, P=0.0000003; OR=2.33; 95% CI=1.18-4.58, P=0.0003). A significant association between intracranial hemorrhage and both proximal extension by using the Fisher's exact test (P=0.031; OR=16.11; 95% CI=0.80-321.2), and composite of propagation to popliteal or to other calf veins (OR=8.28, 95% CI=2.07-33 P=0.001) was observed. Standard anticoagulation significantly reduced the composite of propagation to popliteal or to other calf veins (OR=0.07; 95% CI=0.009-0.61, P=0.007), and all-causes mortality (OR=0.37; 95% CI=0.17-0.8; P=0.02), without a significant increase of bleeding.

CONCLUSIONS

Among inpatients, IDDVT exceeded 60% of DVT. Mortality was not significantly different between IDDVT and PDVT subjects. Intracranial bleeding significantly increased the risk of propagation and death. Although standard anticoagulation decreased both these complications, further targeted studies are needed.

Short-duration chemoprophylaxis might reduce incidence of deep vein thrombosis in Asian patients undergoing total knee arthroplasty

Background

Venous thromboembolism (VTE) is a serious complication that may occur after total knee arthroplasty (TKA), leading to the recommendation of routine chemoprophylaxis by international guidelines. This study aims to determine if short-duration chemoprophylaxis after TKA reduces the incidence of VTE in an Asian population.

Methods

A retrospective study of 316 patients who underwent unilateral primary TKA between 1 January 2011 and 31 December 2013 was conducted. All patients received mechanical prophylaxis. One hundred seventeen patients (37%) received additional chemoprophylaxis, whereas 199 patients (63%) did not. A Doppler ultrasound (DUS) of both lower limbs was conducted for all patients within 6 days after surgery (median = 3 days) to assess for both proximal and distal DVT. Chemoprophylaxis in the form of enoxaparin (low molecular weight heparin; LMWH), aspirin, or heparin was administered until patients had a normal DUS, for a median duration of 4 days. Patients were followed up clinically for a minimum of 6 months to monitor for delayed or recurrent VTE and at least 2 years for patient-reported outcome measures.

Results

Overall, 24 patients (7.59%) developed deep vein thrombosis (DVT): three proximal and 21 distal DVTs. Twenty-three of the 24 patients were asymptomatic. Twenty of 199 patients (10.05%) with only mechanical prophylaxis developed DVT, whereas four of 117 patients (3.42%) with additional chemoprophylaxis developed DVT. Multivariate analysis showed that chemoprophylaxis use was associated with reduced incidence of DVT (odds ratio = 0.19, p value = 0.011). Other factors associated with increased DVT incidence include female gender (odds ratio = 5.45, p value = 0.034), positive history of cancer (odds ratio = 5.14, p value = 0.044), and increased length of stay in hospital (odds ratio = 1.19, p value < 0.001).

Conclusions

Our study has shown that despite the low incidence of DVT in Asian patients undergoing TKA, short-duration chemoprophylaxis might be effective in reducing the incidence of DVT. However, most DVTs observed in our study were distal and may be of limited clinical significance. Further studies are needed to investigate the impact of chemoprophylaxis use on the incidence of PE and overall mortality rates among Asian patients.

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.

Venous Thromboembolism in Neurocritical Care Patients

BACKGROUND

Venous thromboembolism (VTE) is a potentially life-threatening complication among critically ill patients. Neurocritical care patients are presumed to be at high risk for VTE; however, data regarding risk factors in this population are limited. We designed this study to evaluate the frequency, risk factors, and clinical impact of VTE in neurocritical care patients.

METHODS

We obtained data from the electronic medical record of all adult patients admitted to neurological intensive care unit (NICU) at Henry Ford Hospital between January 2015 and March 2018. Venous thromboembolism was defined as deep vein thrombosis, pulmonary embolism, or both diagnosed by Doppler, chest computed tomography (CT) angiography or ventilation-perfusion scan >24 hours after admission. Patients with ICU length of stay <24 hours or who received therapeutic anticoagulants or were diagnosed with VTE within 24 hours of admission were excluded.

RESULTS

Among 2188 consecutive NICU patients, 63 (2.9%) developed VTE. Prophylactic anticoagulant use was similar in patients with and without VTE (95% vs 92%; P = .482). Venous thromboembolism was associated with higher mortality (24% vs 13%, P = .019), and longer ICU (12 [interquartile range, IQR 5-23] vs 3 [IQR 2-8] days, P < .001) and hospital (22 [IQR 15-36] vs 8 [IQR 5-15] days, P < .001) length of stay. In a multivariable analysis, potentially modifiable predictors of VTE included central venous catheterization (odds ratio [OR] 3.01; 95% confidence interval [CI], 1.69-5.38; P < .001) and longer duration of immobilization (Braden activity score <3, OR 1.07 per day; 95% CI, 1.05-1.09; P < .001). Nonmodifiable predictors included higher International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) scores (which accounts for age >60, prior VTE, cancer and thrombophilia; OR 1.66; 95% CI, 1.40-1.97; P < .001) and body mass index (OR 1.05; 95% CI, 1.01-1.08; P = .007).

CONCLUSIONS

Despite chemoprophylaxis, VTE still occurred in 2.9% of neurocritical care patients. Longer duration of immobilization and central venous catheterization are potentially modifiable risk factors for VTE in critically ill neurological patients.

Doppler ultrasound and D-dimer

The diagnosis of venous thromboembolism has evolved considerably with the development of standardized diagnostic algorithms that include clinical probability assessment, D-dimer measurement and the use of non-invasive imaging modalities such as compression ultrasonography and computed tomography angiography. The implementation of these strategies aims to improve resource allocation and patient outcome. The judicious use of these diagnostic tools requires a thorough knowledge of the appropriate clinical setting in which every test and strategy is efficient and can be used safely. For this purpose, D-dimer measurement and compression ultrasonography are complementary: the former is mainly used to exclude VTE in selected patients, while the latter is used to confirm the presence of an underlying DVT.

This review provides an appraisal of the features and use of D-dimer and compression ultrasonography in the context of suspected venous thromboembolism.

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.

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.

Factors predicting venous thromboembolism after spine surgery

BACKGROUND

A meta-analysis was performed to explore predicted factors of venous thromboembolism (VTE) after surgery in the treatment for spine degeneration diseases.

SUMMARY OF BACKGROUND DATA

Many scholars have focused on VTE after spine surgery, but as for the risk factors of VTE have not reached a consensus.

METHODS

An extensive search of literature, "spine or spinal," "degeneration," "after surgery or postoperation," and "venous thromboembolism" as key words, was performed in PubMed/MEDLINE, Embase, the Cochrane library, CNKI, and WANFANG databases. The following variables were extracted: wearing elastic stocking, hypertension (HT), heart disease, diabetes, drinking, anticoagulant therapy, walking disability preoperation, smoking, sex, age, surgical duration, fusion versus nonfusion (lumbar fusion vs lumbar discectomy), surgical site (cervical vs lumbar), blood loss, and body mass index. Data analysis was conducted with RevMan 5.3 and STATA 12.0.

RESULTS

A total of 12 studies were identified, including 34,597 patients of whom 624 patients had VTE, and the incidence of VTE was 2% in all patients who underwent spine surgery. The incidence of VTE for Asian patients was 7.5%, compared with 1% VTE for Occidental patients; the difference was significant (P < 0.0001). The pooled analysis showed that there were significant differences regarding wearing elastic stocking (odds ratio [OR] = 11.71, 95% confidence interval [CI] [1.46, 94.00], P = 0.02), walking disability preoperation (OR = 4.80, 95% CI [2.53, 9.12], P < 0.00001), surgical site (lumbar surgery) (OR = 0.23, 95% CI [0.20, 0.27], P < 0.00001), HT (OR = 1.59, 95% CI [1.21, 2.10], P = 0.001), and diabetes (OR = 2.12, 95% CI [1.09, 4.10], P = 0.03). However, there were no significant differences in blood loss, heart disease, smoking, sex, surgical duration, body mass index, surgical duration, anticoagulant therapy, wearing elastic stocking, fusion versus nonfusion, drinking, and age (all P > 0.05).

CONCLUSIONS

Based on our meta-analysis, Asian patients, patients with walking disability preoperation, patients wearing elastic stocking, patients having undergone lumbar surgery, patients with a history of HT, and patients experiencing diabetes have a higher incidence of VTE after spine surgery.

Controversies in venous thromboembolism: the unique case of isolated distal deep vein thrombosis

Venous thromboembolism (VTE) represents the third leading cause of cardiovascular mortality, and it is the main cause of preventable mortality in hospitalized patients. Among VTE, there is the unique case of isolated distal deep vein thrombosis (IDDVT), which still lacks an agreement in terms of optimal therapeutic strategy. Although most IDDVTs are self-limiting and associated with a very low risk of embolic complications, still not all IDDVTs can be safely identified as stable. Lack of strong scientific evidence, fear of thromboembolic complications, and risk of bleeding upon initiation of anticoagulant treatment result in very heterogeneous therapeutic strategies among physicians. Here, we provide a comprehensive review of the literature, highlight the many controversial issues regarding IDDVTs, and call for a consensus of experts aimed to shed new light on the gray areas of IDDVT management and therapy.

Prevalence and risk factors for development of venous thromboembolism after degenerative spinal surgery

STUDY DESIGN

Prospective clinical study.

OBJECTIVE

To identify the incidence and risk factors for venous thromboembolism (VTE) associated with degenerative spinal surgery procedures at the different spinal levels for various pathologies.

SUMMARY OF BACKGROUND DATA

Spinal surgery includes procedures for treatment of various pathologies at different spinal levels. There have been no studies on VTE after degenerative spinal surgery with respect to screening patients for both deep venous thrombosis and pulmonary thromboembolism (PE).

METHODS

We prospectively investigated the occurrence of VTE after degenerative spinal surgery in 459 patients who were divided into 5 groups: group 1, patients with cervical degenerative disease treated with posterior decompression; group 2, patients with cervical degenerative disease treated with instrumentation for spinal fusion; group 3, patients with thoracolumbar degenerative disease treated with instrumentation for spinal fusion; group 4, patients with lumbar spinal stenosis treated with posterior decompression; and group 5, patients with lumbar spondylolisthesis treated with 1-level posterior lumbar interbody fusion. A deep venous thrombosis and PE screening was performed for all patients. Binomial logistic regression analysis was used to assess the association of risk factors.

RESULTS

The incidence of VTE was 2.8%, 3.4%, 10.8%, 12.5%, and 10.1% in groups 1, 2, 3, 4, and 5, respectively. Female sex, advanced age, spinal level, and neurological deficits, were all risk factors. Cervical spinal surgery in particular had an associated low risk. In patients with PE, 3 of the 4 had no deep venous thrombosis, indicating that screening for PE is also needed in high-risk patients.

CONCLUSION

The prevalence of VTE after elective spinal surgery was different in each group.

LEVEL OF EVIDENCE

3.

Guidelines in Emergency Medicine Network (GEMNet): guideline for the use of thromboprophylaxis in ambulatory trauma patients requiring temporary limb immobilisation

The Guidelines in Emergency Medicine Network (GEMNet) has been created to promote best medical practice in a range of conditions presenting to emergency departments (EDs) in the UK. This guideline presents a summary of the best available evidence to guide the use of thromboprophylaxis in adult ambulatory outpatients who present to the ED following acute limb trauma and require temporary immobilisation. The document has been developed following discussion among emergency physicians and collegiate fellows to decide which topics would benefit from the development of clinical guidelines. The document is intended as a guideline for use in the ED by emergency physicians and is based on the review of the best existing evidence for treatments used in this setting. The document is summarised as a Clinical Decision Support Guideline that has been presented as an easy to follow algorithm. The intention is for each guideline to be updated and reviewed as further evidence becomes available. The formal revision date has been set at 5 years from publication, though the guideline is subject to continuous informal review.

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.

Diagnosis of DVT: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

Objective testing for DVT is crucial because clinical assessment alone is unreliable and the consequences of misdiagnosis are serious. This guideline focuses on the identification of optimal strategies for the diagnosis of DVT in ambulatory adults.

METHODS

The methods of this guideline follow those described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines.

RESULTS

We suggest that clinical assessment of pretest probability of DVT, rather than performing the same tests in all patients, should guide the diagnostic process for a first lower extremity DVT (Grade 2B). In patients with a low pretest probability of first lower extremity DVT, we recommend initial testing with D-dimer or ultrasound (US) of the proximal veins over no diagnostic testing (Grade 1B), venography (Grade 1B), or whole-leg US (Grade 2B). In patients with moderate pretest probability, we recommend initial testing with a highly sensitive D-dimer, proximal compression US, or whole-leg US rather than no testing (Grade 1B) or venography (Grade 1B). In patients with a high pretest probability, we recommend proximal compression or whole-leg US over no testing (Grade 1B) or venography (Grade 1B).

CONCLUSIONS

Favored strategies for diagnosis of first DVT combine use of pretest probability assessment, D-dimer, and US. There is lower-quality evidence available to guide diagnosis of recurrent DVT, upper extremity DVT, and DVT during pregnancy.

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.

A Novel Scoring System for Lower-extremity Venous Pathology Analysed Using Magnetic Resonance Venography and Duplex Ultrasound

Objectives:

To present a novel scoring system for lower-extremity venous pathology (the LOVE score) and our experiences using it in our clinical practice to identify venous pathology with duplex ultrasound (DUS) and magnetic resonance venography (MRV).

Method:

A total of 40 patients, 30 suspected of chronic venous disease and 10 with acute deep vein thrombosis (DVT) were examined from the inferior vena cava (IVC) to the popliteal vein using DUS and MRV. The image findings were reported using the LOVE score.

Results

The majority of deep veins (368 out of 378 segments) were completely visualized by both our imaging techniques and could be analysed using the LOVE score. Both imaging techniques reported comparable findings with regard to the visualization of thrombus, obstruction, collaterals, trabeculations, anatomic variations and central venous compression (e.g. May–Thurner).

Conclusions:

The LOVE score can be used to expand and standardize the documentation of imaging the deep venous system beyond thrombosis, to help identify (optimal) treatment options in patients with venous disease, in both the clinical and research setting. This first assessment shows that both DUS and MRV are capable of systematically identifying a multitude of changes in the venous system.

An Imaging Approach to Deep Vein Thrombosis and the Lower Extremity Thrombosis Classification

In this article we want to discuss the potential of lower extremity deep vein thrombosis (DVT) imaging and propose a systematic approach to DVT management based on a DVT classification of the lower extremity; the LET classification. Identifying and reporting DVT more systematically allows for accurate stratification for initial patient care, future clinical trials and appropriate descriptions for natural history studies.

Clinical applications of bedside ultrasonography in internal and emergency medicine

Ultrasonography (US) is an invaluable tool in the management of many types of patients in Internal Medicine and Emergency Departments, as it provides rapid, detailed information regarding abdominal organs and the cardiovascular system, and facilitates the assessment and safe drainage of pleural or intra-abdominal fluid and placement of central venous catheters. Bedside US is a common practice in Emergency Departments, Internal Medicine Departments and Intensive Care Units. US performed by clinicians is an excellent risk reducing tool, shortening the time to definitive therapy, and decreasing the rate of complications from blind invasive procedures. US can be performed at different levels of practice in Internal Medicine, according to the experience of ultrasound practitioners and equipment availability. In this review, the indications for bedside US that can be performed with basic or intermediate US training will be highlighted.

Complications of heel surgery

Surgical complications of the calcaneus are unique to that structure but do not have a greater incidence than in any other part of the foot or ankle. The first tenet of any complication, however, is to recognize it. When all is said and done, recognition is probably the most important step when a complication arises.

Current treatment of venous thromboembolism

Venous thromboembolism, comprising deep vein thrombosis and pulmonary embolism, is a common disorder with at least 250 000 new events occurring each year in the United States alone. Treatment of venous thromboembolism includes anticoagulation, which is achieved initially with the use of a parenterally administered agent followed by a more prolonged course of treatment with an oral vitamin K antagonist. The duration of treatment depends on the clinical assessment of the benefit-to-risk ratio of prolonged anticoagulation versus the risk of recurrent events. In this review, we discuss some of the issues that we believe are among the most critical unanswered questions in the management of venous thromboembolism in the present era.

Diagnosis and initial treatment of venous thromboembolism in patients with cancer

PURPOSE

Venous thromboembolism (VTE) is a common complication of cancer and its therapy. The purpose of this article is to review the diagnosis and initial treatment of VTE in the patient with cancer.

METHODS

I conducted a survey of the English-language literature on topics relevant to the diagnosis and initial treatment of VTE in patients with cancer.

RESULTS

Patients with cancer are at increased risk for VTE because of the presence of multiple risk factors for thrombotic disease. The most common signs and symptoms of VTE as well as the utility of clinical prediction rules and D-dimer testing in the diagnosis of VTE in the patient with cancer are reviewed. Duplex ultrasound and computer tomography angiography are the primary objective diagnostic modalities for VTE. Low molecular weight heparin is the preferred initial therapy for VTE. Until further data emerge, thrombolysis and vena cava filters should be reserved for patients in whom anticoagulation is insufficient or contraindicated. Outpatient management is feasible for carefully selected patients with cancer with deep vein thrombosis (DVT) and low-risk pulmonary embolism. Anticoagulation is the preferred initial therapy for cancer patients with central venous catheter-associated DVT, calf DVT, and unsuspected VTE.

CONCLUSION

Optimal initial management of VTE in patients with cancer entails maintaining a high index of suspicion for thrombotic disease, confirming diagnostic suspicions with objective testing and evidence-based use of anticoagulation, and adjunctive therapeutic modalities (thrombolysis, vena cava interruption, venous stenting). Further investigation of initial diagnostic and treatment strategies for VTE focusing on patients with cancer are warranted.

Do not forget the distal lower limb veins in screening patients with spinal cord injuries for deep venous thromboses

In this prospective study, we aimed to document the rate and localization of deep venous thromboses in patients with spinal cord injuries. Patients with paraplegia or tetraplegia were screened by a serial color duplex sonography protocol for deep venous thrombosis within the first 36 hours after admission, at day 7, and at day 21. Sonography was performed by a complete scan including the veins below the knee. A total of 139 patients were included (19-90 years, 63.5% male). Cumulative rate of deep venous thrombosis after 3 duplex scans was 45.3% (n = 63). In 71.4% (n = 45), thromboses were localized below the knee. Because of the relevant number of distal vein thromboses, inclusion of the calf veins during screening scans is suggested. Further studies are needed to analyze the clinical benefit of diagnosing and treating distal vein thromboses.