Current diagnosis of venous thromboembolism in primary care: a clinical practice guideline from the American Academy of Family Physicians and the American College of Physicians

Antegrade and Retrograde Approaches with a Mechanical Thrombectomy Device for the Treatment of Acute Lower Limb Deep Vein Thrombosis

OBJECTIVE

To examine the efficacy of antegrade and retrograde approaches with the AngioJet thrombectomy device for the treatment of acute lower limb deep vein thrombosis (DVT) and to evaluate the necessity of filter placement.

METHODS

The clinical data of patients with acute lower limb DVT treated with the AngioJet device from January 2021 to June 2023 were retrospectively analyzed. The patients were divided into the antegrade and retrograde treatment groups according to the surgical approach and the direction of valve opening. The thrombosis interception rate of the filter, incidence of pulmonary embolism (PE), thrombectomy effectiveness, venous obstruction rate, and thrombosis recurrence rate of each treatment group were evaluated. In addition, factors affecting patency were analyzed.

RESULTS

AngioJet was employed for 84 patients with acute lower limb DVT, treating a total of 88 limbs. The thrombosis interception rate of the filter was 35.7% (30 patients). The incidence of new PE or PE exacerbation was 6.0% (5 patients), and a filter retrieval rate of 97.6% (82 patients) was detected. Thrombus removal of grade III occurred in 35 (64.8%) of the 54 limbs (61.4%) in the antegrade treatment group versus 13 (38.2%) of the 34 limbs (38.6%) in the retrograde treatment group (P < 0.05). At 3 months, venous patency and bleeding events involved 52 (96.3%) and 4 (7.4%) limbs in the antegrade treatment group, respectively, versus 29 (85.3%) and 2 (5.9%) in the retrograde treatment group, respectively (P > 0.05). Regression analysis was performed to determine factors that may affect 3-month patency in both groups. Statistically significant linear relationships were found between 3-month patency and thrombus removal rate [odds ratio [OR] = 0.546 (0.326, 0.916)], thrombus formation time [OR = 1.018 (1.002, 1.036)], and preoperative thrombosis score [OR = 1.012 (1.002, 1.022)] in the antegrade treatment group, as well as thrombus removal rate [0.473 (0.229, 0.977)] in the retrograde treatment group. In regression analysis of factors affecting patency in both groups and the venous clinical severity score/Villalta score, a statistically significant linear relationship was found between thrombus formation time and the venous clinical severity score in the antegrade treatment group [0.576 (0.467, 0.710)].

CONCLUSIONS

Both antegrade and retrograde approaches are safe and effective for the treatment of acute lower limb DVT. There are no differences in 3-month deep vein patency and post-thrombotic syndrome (PTS) incidence rates. Individuals with acute lower limb DVT are at high risk of thrombus shedding after treatment with AngioJet thrombectomy, and placement of a vena cava filter (VCF) is recommended for effective interception.

Guidelines on deep vein thrombosis of the Brazilian Society of Angiology and Vascular Surgery

Deep vein thrombosis is one of the main causes of inpatient and outpatient morbidity, both in medical and surgical patients, significantly impacting mortality statistics and requiring prompt diagnosis so that treatment can be initiated immediately. This document was prepared and reviewed by 11 specialists certified by the Brazilian Society of Angiology and Vascular Surgery, who searched the main databases for the best evidence on the diagnostic (physical examination, imaging) and therapeutic approaches (heparin, coumarins, direct oral anticoagulants, fibrinolytics) to the disease.

Relationship of the Novel Scoring System for Lower Extremity Venous Thrombosis with Pulmonary Embolism

RATIONALE AND OBJECTIVE

To develop a new scoring system, the "Lower extremity venous Doppler ultrasound scoring system" (LEVDUS), to predict the diagnosis of pulmonary embolism (PE) localization in patients with deep vein thrombosis (DVT).

METHODS

This single-center retrospective study included 182 patients aged ≥ 18 years. We used scoring according to thrombosis localization and stage in Doppler US. Patients with PE were divided into three categories based on the pulmonary artery (PA) location on CT pulmonary angiography. LEVDUS values were compared according to the PE classification. The threshold value was determined for the diagnosis of PE in the receiver operating characteristics analysis. Factors affecting the diagnosis of PE were evaluated by logistic regression analysis.

RESULTS

A total of 182 patients were included (female patients: 55.5% [101/182]). The median age of the patients was 68 (IQR, 56-77). The rates of DVT and PE were 35.2% (64/182) and 52.7% (96/182), respectively. Although the median LEVDUS and d-dimer values in the subsegmental PE group were higher, LEVDUS was statistically significant but d-dimer was not (p = 0.005 and p = 0.022, respectively). In addition, both LEVDUS and d-dimer median values in the other PE groups were statistically significantly higher than the non-PE group (p < 0.001). The cut-off value for the diagnosis of PE was LEVDUS≥ 2.5. LEVDUS was 1.2-fold higher for the presence of PE.

CONCLUSION

LEVDUS provides useful information in predicting the presence of PE in patients and provides a common diagnostic language between radiologists and emergency or clinic physicians.

Emergency medicine residents' learning curve in diagnosing deep vein thrombosis with 3-point venous point-of-care ultrasound

BACKGROUND

Many cases of deep vein thrombosis (DVT) are diagnosed in the emergency department, and abbreviated lower extremity venous point-of-care ultrasound (POCUS) has already shown an accuracy comparable to that of specialists. This study aimed to identify the learning curve necessary for emergency medicine (EM) residents to achieve expertise-level accuracy in diagnosing DVT through a 3-point lower extremity venous POCUS.

METHODS

This prospective study was conducted at an emergency department between May 2021 and October 2022. Four EM residents underwent a one-hour POCUS training session and performed DVT assessments in participants with DVT symptoms or confirmed pulmonary embolism. POCUS was performed at three proximal lower extremity sites to evaluate the thrombi presence and vein compressibility, with results validated by specialized radiology ultrasound. Cumulative sum (CUSUM) and the Bush and Mosteller models were used to analyze the learning curve, while generalized estimating equations were used to identify factors affecting diagnostic accuracy.

RESULTS

91 POCUS scans were conducted in 49 patients, resulting in 22% DVT confirmed by specialized venous ultrasound. In the CUSUM analysis, all four EM residents attained a 90% success rate at the common femoral vein, whereas only half achieved this rate when all three sites were considered. According to Bush and Mosteller models, 13-18 cases are required to attain 90-95% diagnostic accuracy. After 10-16 cases, the examination time for each resident decreased, and a 20% increase in examiner confidence was linked to a 2.506-fold increase in the DVT diagnosis accuracy.

CONCLUSION

EM residents generally required 13-18 cases for 90-95% DVT diagnostic accuracy, but proficiency varied among individuals, particularly requiring more cases for regions outside the common femoral vein.

The Diagnostic Utility of Natural Killer Cell Subsets in Deep Vein Thrombosis

Background

Natural killer (NK) cells are important components of adaptive and innate immune responses. NK cell subsets have different functions and may play a role in vascular disorders. This study aimed to evaluate the proportions of NK cells and their subsets to determine whether they can be used as markers of venous thrombosis and to identify whether there was a link between NK cell proportion and citrullinated histone (H3) levels.

Patients and Methods

This study included 100 participants divided into Group I (n=50, patients with deep venous thrombosis (DVT)) and Group II (n=50, age- and sex-matched healthy controls). Group I was further categorized into Group Ia (n=25, patients with acute DVT) and Group Ib (n=25, patients with chronic DVT). The proportions of NK cells and their subsets were evaluated by flow cytometry using CD3/CD16/CD56. The levels of citrullinated histones (H3) were estimated using enzyme-linked immunosorbent assay (ELISA).

Results

Compared to the control group, DVT patients had a significantly lower proportion of (CD56 dim/CD16+) NK cells, a significantly higher proportion of (CD56-/CD16+) NK cells and a high level of citrullinated histone (H3).

Conclusion

NK cell subsets and citrullinated histone (H3) could be used as markers for DVT and as targets for therapeutic drugs to inhibit the formation or progression of thrombosis.

Reduced ADAMTS13 activity and high D-dimer levels are associated with thrombosis in patients with systemic lupus erythematosus

INTRODUCTION

Patients with systemic lupus erythematosus (SLE) have an increased risk of vascular thrombosis compared to the general population. Therefore, biomarkers for predicting the risk of thrombosis in patients with SLE are needed.

METHODS

In the present study, a total of 66 patients with SLE (22 with and 44 without a history of thrombosis) were enrolled. The cases with thrombosis and the controls without thrombosis were matched for age (± 5 years) and sex. We assessed ADAMTS13 activity, D-dimer levels, and antiphospholipid antibodies. Clinical manifestations, SLE disease activity, classical risk factors, and medical history were collected.

RESULTS

ADAMTS13 activity was significantly reduced, and D-dimer levels were significantly increased in patients with SLE with a history of thrombosis compared with those in patients without thrombosis. Receiver operating characteristic curve analysis revealed a good correlation between reduced ADAMTS13 activity and a history of thrombosis. Reduced ADAMTS13 activity was correlated with increased D-dimer levels only in the thrombotic group.

CONCLUSION

Reduced ADAMTS13 activity and high D-dimer levels are associated with thrombosis and may serve as prognostic markers for thrombosis in patients with SLE.

Optimal management, prevalence, and clinical behavior of saddle pulmonary embolism: A systematic review and meta-analysis

INTRODUCTION

The central location, size, and instability of saddle pulmonary embolism (SPE) have raised significant concerns regarding its clinical, hemodynamic effects as well as optimal management. Pulmonary embolism (PE) guidelines barely address such concerns. We aimed to pool the available data on the clinical behavior and outcomes of SPE and study the effects of various treatment modalities on mortality outcomes.

METHODS

PubMed, Scopus, and Google Scholar were searched for articles (any date up to February 28, 2022) reporting patients with SPE. Data on SPE demographics, clinical characteristics, management, and outcomes were extracted and analyzed.

RESULTS

Results from all SPE cases: A total of 5251 patients from 194 studies were included in the review. Dyspnea (57 %) was the most prevalent symptom. Massive and submassive PE comprised 9.7 % and 45.8% of cases, respectively. Thrombolytic therapy (TT) was administered in 18.1 %, and thrombectomy was performed in 16 % of cases. SPE-related mortality was observed in 4.6 %, late decompensation in 9.5 %, and PE recurrence in 4.5 % of cases. Female sex (61.5 % vs. 41.3 %, p = 0.019), hypoxemia (90 % vs. 59.2 %, p < 0.001), massive PE features (89.7 % vs. 30.1 %, p < 0.001), associated chronic kidney disease (CKD) (10.3 % vs. 1.4 %, p = 0.002), and the need for mechanical ventilation (28.2 % vs. 13.1 %, p = 0.02) were significantly associated with increased mortality. The use of TT was significantly associated with increased survival (27.1 % vs. 12.5 %, p < 0.001). In a multivariate logistic regression model, massive PE features significantly increased the odds of death (OR: 29.3, CI: 4.86-181.81, p < 0.001), whereas, treatment with anticoagulation (AC) alone (OR: 0.1, CI: 0.027-0.356, p < 0.001), TT (OR: 0.065, CI: 0.019-0.26, p < 0.001), surgical thrombectomy (ST) (OR: 0.047, CI: (0.010-0.23), p < 0.001), or percutaneous thrombectomy (PT) (OR: 0.12, CI: 0.020-0.84, p = 0.032) significantly decreased odds of death. Results from a meta-analysis of observational studies: Meta-analysis of the included 17 observational studies revealed an overall 10 % (95 % CI: 4.56-16.89) SPE prevalence among all PE cases. The overall SPE-related mortality rate was 8 % (95 % CI: 5.26-10.96). Massive PE was observed in 13.3 % (95 % CI: 5.56-23.70), PE recurrence in 5.1 % (95 % CI: 2.22-9.05), and late decompensation in 11 % (95 % CI: 3.43-22.34) of patients.

CONCLUSIONS

SPE comprises 10 % of all PE cases. Despite its ominous radiologic appearance, the clinical, hemodynamic, and mortality outcomes of SPE seem comparable to that of other PE types in general. The presence of massive PE features is the main predictor of mortality in SPE patients. AC, TT, ST, and PT are all associated with decreased odds of death from SPE.

Incremental value of compression ultrasound sonography in the emergency department

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

The Use of Point-of-Care Ultrasound (POCUS) in the Diagnosis of Deep Vein Thrombosis

Acute lower extremity proximal deep venous thrombosis (DVT) requires accurate diagnosis and treatment in order to prevent embolization and other complications. Point-of-care ultrasound (POCUS), a clinician performed, and clinician interpreted bedside ultrasound examination has been increasingly used for DVT evaluation mainly in the urgent and critical care setting, but also in the ambulatory clinics and the medical wards. Studies have demonstrated that POCUS has excellent diagnostic accuracy for acute proximal DVT when performed by well-trained users. However, there is significant heterogeneity among studies on the necessary extent of training and universally acceptable standardized education protocols are needed. In this review, we summarize the evidence that supports the use of POCUS to diagnose acute proximal DVT and focus on methodology and current technology, sensitivity and specificity, pre-test probability and the role of D-dimer, time and resources, education, limitations, and future directions.

Comprehensive management of acute pulmonary embolism in primary care using telemedicine in the COVID-era

A healthy, active woman in her 70s reported intermittent exertional dyspnoea for 2 months, notable during frequent open-water swimming. Symptoms were similar to an episode of travel-provoked pulmonary embolism 3 years prior. She denied chest pain, cough, fever, extremity complaints and symptoms at rest. Due to the COVID-19 pandemic, her healthcare system was using secure telemedicine to evaluate non-critical complaints. During the initial video visit, she appeared well, conversing normally without laboured breathing. An elevated serum D-dimer prompted CT pulmonary angiography, which identified acute lobar pulmonary embolism. After haematology consultation and telephone conversation with the patient, her physician prescribed rivaroxaban. Her symptoms rapidly improved. She had an uneventful course and is continuing anticoagulation indefinitely. The pandemic has increased the application of telemedicine for acute care complaints. This case illustrates its safe and effective use for comprehensive management of acute pulmonary embolism in the primary care setting.

Diagnostic Accuracy of a Three-point Compression Ultrasonography Performed by Emergency Medicine Resident for the Diagnosis of Deep Vein Thrombosis: a Prospective Diagnostic Study

INTRODUCTION

Deep vein thrombosis (DVT) is a common cause of admission to the emergency departments (ED). Doppler ultrasonography of the entire lower limb is the first-line imaging modality. But most EDs do not access to full-time radiologists which can lead to delayed diagnosis.

AIM

The aim of this study was to evaluate the diagnostic accuracy of three-point compression ultrasonography performed by emergency medicine resident for diagnosis of DVT.

METHODS

This prospective diagnostic study was carried out at Imam Khomeini Hospital in Sari from March 2018 to November 2018. For all patients with suspected lower extremity DVT, first bedside 3-point compression ultrasound were performed by a third year emergency medicine resident at ED. Then Doppler ultrasonography were performed by a radiologist in the radiology department, as a reference test. Sensitivity, specificity, and positive predictive value of the three-point compression ultrasound performed by emergency medicine resident was calculated.

RESULTS

Of the 72 patients enrolled in our study, 50% of the patients were male, with an average age of 36±19 years. The mean of patient admission time to perform ultrasonography by an emergency medicine resident and radiologist were 14.05±19 and 216±140.1 minutes, respectively. The two groups had a statistically significant difference (P<0.0001). In ultrasonography performed by emergency medicine resident and doper ultrasonography by radiologist, 91.67% and 36.1% of patients were diagnosed with DVT, respectively. Although the ultrasonography performed by emergency medicine resident has a relatively low sensitivity (53.8%), it has a good specificity (85.7%). The positive and negative predictive value was 70 and 75%, respectively.

CONCLUSION

Although the results of this study indicate insufficient sensitivity of bedside three-point compression ultrasound performed by emergency medicine resident in diagnosis of lower limb DVT, the specificity, positive and negative predictive values and positive likelihood ratio were almost appropriate.

General practitioner use of D-dimer in suspected venous thromboembolism: historical cohort study in one geographical region in the Netherlands

OBJECTIVES

To investigate how many general practitioner (GP)-referred venous thromboembolic events (VTEs) are diagnosed during 1 year in one geographical region and to investigate the (urgent) referral pathway of VTE diagnoses, including the role of laboratory D-dimer testing.

DESIGN

Historical cohort study.

SETTING

GP patients of 47 general practices in a demarcated geographical region of 161 503 inhabitants in the Netherlands.

PARTICIPANTS

We analysed all 895 primary care patients in whom either the GP determined a D-dimer value or who had a diagnostic work-up for suspected VTE in a non-academic hospital during 2015.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcomes of this study were the total number of VTEs per year and the diagnostic pathways-including the role of GP determined D-dimer testing-of patients urgently referred to secondary care for suspected VTE. Additionally, we explored the use of an age-adjusted D-dimer cut-off.

RESULTS

The annual VTE incidence was 0.9 per 1000 inhabitants. GPs annually ordered 5.1 D-dimer tests per 1000 inhabitants. Of 470 urgently GP-referred patients, 31.3% had a VTE. Of those urgently referred based on clinical assessment only (without D-dimer testing), 73.8% (96/130) had a VTE; based on clinical assessment and laboratory D-dimer testing yielded 15.0% (51/340) VTE. Applying age-adjusted D-dimer cut-offs to all patients aged 50 years or older resulted in a reduction of positive D-dimer results from 97.9% to 79.4%, without missing any VTE.

CONCLUSIONS

Although D-dimer testing contributes to the diagnostic work-up of VTE, GPs have a high detection rate for VTE in patients who they urgently refer to secondary care based on clinical assessment only.

Evaluation of unmet clinical needs in prophylaxis and treatment of venous thromboembolism in high-risk patient groups: cancer and critically ill

Background

Clinical practice shows that venous thromboembolism (VTE) presents a substantial burden in medical patients, and awareness and advocacy for its primary and secondary prevention remains inadequate. Specific patient populations, such as those with cancer and the critically ill, show elevated risk for VTE, bleeding or both, and significant gaps in VTE prophylaxis and treatment exist in these groups.

Objective

To present novel insights and consolidated evidence collected from experts, clinical practice guidelines and original studies on the unmet needs in thromboprophylaxis, and on the treatment of VTE in two high-risk patient groups: patients with cancer and the critically ill.

Methodology

To identify specific unmet needs in the management of VTE, a methodology was designed and implemented that assessed gaps in prophylaxis and treatment of VTE through interviews with 44 experts in the field of thrombosis and haemostasis, and through a review of current guidelines and seminal studies to substantiate the insights provided by the experts. The research findings were then analysed, discussed and consolidated by a multidisciplinary group of experts.

Results

The gap analysis methodology identified shortcomings in the VTE risk assessment tools, patient stratification approaches for prophylaxis, and the suboptimal use of anticoagulants for primary prophylaxis and treatment.

Conclusions

Specifically, patients with cancer need better VTE risk assessment tools to tailor primary thromboprophylaxis to tumour types and disease stages, and the potential for drug–drug interactions needs to be considered. In critically ill patients, unfractionated heparin is not advised as a first-line treatment option, and the strength of evidence is increasing for direct oral anticoagulants as a treatment option over low-molecular-weight heparins.

Electronic supplementary material

The online version of this article (10.1186/s12959-019-0196-6) contains supplementary material, which is available to authorized users.

A Clinically Meaningful Interpretation of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II and III Data

RATIONALE AND OBJECTIVES

This study aimed to calculate the multiple-level likelihood ratios (LRs) and posttest probabilities for a positive, indeterminate, or negative test result for multidetector computed tomography pulmonary angiography (MDCTPA) ± computed tomography venography (CTV) and magnetic resonance pulmonary angiography (MRPA) ± magnetic resonance venography (MRV) for each clinical probability level (two-, three-, and four-level) for the nine most commonly used clinical prediction rules (CPRs) (Wells, Geneva, Miniati, and Charlotte). The study design is a review of observational studies with critical review of multiple cohort studies. The settings are acute care, emergency room care, and ambulatory care (inpatients and outpatients).

MATERIALS AND METHODS

Data were used to estimate pulmonary embolism (PE) pretest probability for each of the most commonly used CPRs at each probability level. Multiple-level LRs (positive, indeterminate, negative test) were generated and used to calculate posttest probabilities for MDCTPA, MDCTPA + CTV, MRPA, and MRPA + MRV from sensitivity and specificity results from Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II and PIOPED III for each clinical probability level for each CPR. Nomograms were also created.

RESULTS

The LRs for a positive test result were higher for MRPA compared to MDCTPA without venography (76 vs 20) and with venography (42 vs 18). LRs for a negative test result were lower for MDCTPA compared to MRPA without venography (0.18 vs 0.22) and with venography (0.12 vs 0.15). In the three-level Wells score, the pretest clinical probability of PE for a low, moderate, and high clinical probability score is 5.7, 23, and 49. The posttest probability for an initially low clinical probability PE for a positive, indeterminate, and negative test result, respectively, for MDCTPA is 54, 5 and 1; for MDCTPA + CTV is 52, 2, and 0.7; for MRPA is 82, 6, and 1; and for MRPA + MRV is 72, 3, and 1; for an initially moderate clinical probability PE for MDCTPA is 86, 22, and 5; for MDCTPA + CTV is 85, 10, and 4; for MRPA is 96, 25, and 6; and for MRPA + MRV is 93, 14, and 4; and for an initially high clinical probability of PE for MDCTPA is 95, 47, and 15; for MDCTPA + CTV is 95, 27, and 10; for MRPA is 99, 52, and 17; and for MRPA + MRV is 98, 34, and 13.

CONCLUSIONS

For a positive test result, LRs were considerably higher for MRPA compared to MDCTPA. However, both a positive MRPA and MDCTPA have LRs >10 and therefore can confirm the presence of PE. Performing venography reduced the LR for a positive and negative test for both MDCTPA and MRPA. The nomograms give posttest probabilities for a positive, indeterminate, or negative test result for MDCTPA and MRPA (with and without venography) for each clinical probability level for each of the CPR.

Ultrasound for Lower Extremity Deep Venous Thrombosis

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

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

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

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

Ruling out Pulmonary Embolism in Patients with High Pretest Probability

Introduction

The American College of Emergency Physicians guidelines recommend more aggressive workup beyond imaging alone in patients with a high pretest probability (PTP) of pulmonary embolism (PE). However, the ability of multiple tests to safely rule out PE in high PTP patients is not known. We sought to measure the ability of negative computed tomography pulmonary angiography (CTPA) along with negative D-dimer to rule out PE in these high-risk patients.

Methods

We analyzed data from a previous prospective observational study conducted in 12 emergency departments (ED). Wells score criteria were entered by providers before final PE testing. PE was diagnosed by imaging on the index ED visit, or within 45 days, demonstrating either PE or deep vein thrombosis (DVT), or if the patient died of PE during the 45-day, follow-up period. Testing threshold was set at 1.8%.

Results

A total of 7,940 patients were enrolled and tested for PE, and 257 had high PTP (Wells >6). Sixteen of these high-risk patients had negative CTPA and negative D-dimer, of whom two were positive for PE (12.5% [95% confidence interval {2.2%–40.0%}]). One of these patients had a DVT on CT venogram and the other was diagnosed at follow-up.

Conclusion

Our analysis suggests that in patients with high PTP of PE, neither negative CTPA by itself nor a negative CTPA plus a negative D-dimer are sufficient to rule out PE. More aggressive workup strategies may be required for these patients.

Are All Intracranial Mass Lesions Always a Contraindication for Thrombolytic Therapy?

Thrombolytic therapy is regarded as the first treatment choice in haemodynamically unstable patients with pulmonary embolism. Intracranial tumors have long been considered as a contraindication to thrombolytic therapy due to the risk of intracerebral haemorrhage. In this report, we presented a 76-year-old female patient with meningioma and massive pulmonary embolism who had received thrombolytic therapy despite a contraindication of intracranial mass. The patient completed the thrombolytic therapy without having complication. (Hong Kong j.emerg.med. 2014;21:98-102)

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.

A Clinically Meaningful Interpretation of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) Scintigraphic Data

RATIONALE AND OBJECTIVES

Pulmonary embolism (PE) is a common condition associated with significant morbidity and mortality. Diagnostic test characteristics reported in terms of sensitivity and specificity are difficult to translate at the clinical level. More relevant measures are likelihood ratios (LRs), which can convert a pretest into a posttest probability. The aim of our study was to calculate the LRs and posttest probabilities for multiple-level test result for ventilation/perfusion (V/Q) lung scintigraphy and for perfusion scintigraphy combined with chest radiography using modified Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II and the Prospective Investigative Study of Pulmonary Embolism Diagnosis (PISAPED) criteria for each clinical probability level for the most commonly used clinical prediction rules (CPR) using the PIOPED data.

MATERIALS AND METHODS

PE pretest probability was estimated for the most commonly used CPRs (Wells, Geneva, Miniati, and Charlotte) at each clinical probability level (two-, three-, and four-level). Multiple-level LRs (high, indeterminate, low, very low probability, and normal) and the positive, indeterminate, and negative results for V/Q scintigraphy, and the positive, indeterminate, and negative results for perfusion scintigraphy were generated and used to calculate posttest probabilities based on the sensitivity and specificity data from PIOPED for each clinical probability level (low, intermediate, and high) for each CPR. Nomograms were also created.

RESULTS

The LRs for a positive V/Q and perfusion scintigraphy test using modified PIOPED II and PISAPED criteria were 20.6, 11, and 23.7, and for a negative test result were 0.15, 0.16, and 0.2, respectively. In the three-level Wells score, the posttest probability for an initial low clinical probability PE for a positive, indeterminate, and negative test result, respectively, for V/Q scintigraphy is 56, 5, and 0.9; for perfusion scintigraphy with modified PIOPED 40, 7, and 0.9, and with PISAPED 59, not available (N/A), and 1.2; for an initial moderate clinical probability PE for V/Q scintigraphy 86, .22, and 4; for perfusion scintigraphy with modified PIOPED 77, 26, and 5, and with PISAPED 88, N/A, and 6; for an initial high clinical probability of PE for V/Q scintigraphy 95, 48, and 13; and for perfusion scintigraphy with modified PIOPED 92, 53, and 13, and with PISAPED 96, N/A, and 16.

CONCLUSIONS

With LRs >10, a positive test result for V/Q and perfusion scintigraphy can confirm the presence of PE. Only a normal test result has low enough LR to exclude PE.

Facteurs génétiques à prendre en considération dans le cadre de l'examen gynécologique annuel

OBJECTIF

Offrir aux médecins un survol des troubles génétiques courants qui devraient être pris en considération dans le cadre de l'examen gynécologique annuel d'une patiente, et ce, afin de déterminer le risque que court celle-ci ou d'en venir à procéder à des examens particuliers ou à orienter la patiente vers un autre service de sous-spécialité, en fonction de ses antécédents personnels ou familiaux.

OPTIONS

Ces renseignements d'ordre génétique peuvent être utilisés aux fins de la sensibilisation des patientes et du dépistage ou du diagnostic de possibles maladies et/ou mutations.

ISSUES

L'utilisation de ces renseignements d'ordre génétique pourrait mener à l'amélioration de l'évaluation des risques et des avantages et à celle de la prise en charge dans le cadre de l'examen gynécologique annuel. RéSULTATS: Les études publiées en anglais, jusques et y compris en mai 2010, ont été récupérées par l'intermédiaire de recherches menées dans PubMed et la Cochrane Library au moyen d'un vocabulaire contrôlé (« gynaecological diagnosis », « genetic inheritance ») et de mots clés (« genetic risk », « genetic mutation », « inheritance », « family history », « uterus », « ovary », « endometrial », « vagina », « colon », « gastric », « renal », « breast », « cardiac », « thrombophilia », « diabetes », « epilepsy », « leiomyomata uteri ») appropriés. D'autres sources ont été identifiées par l'intermédiaire de recherches menées dans les sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, dans des registres d'essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales.

VALEURS

Le niveau des résultats ne permet pas la formulation de recommandations factuelles. AVANTAGES, DéSAVANTAGES ET COûTS: La présente opinion de comité améliorera l'utilisation de nouvelles connaissances génétiques et leur application aux soins gynécologiques offerts annuellement aux femmes. Les occasions de gestion du risque et de diagnostic, pour ce qui est des troubles gynécologiques génétiques, s'en trouveront améliorées. Une compréhension plus exhaustive des troubles génétiques pourrait entraîner une hausse de l'anxiété et du stress psychologique chez les femmes et les membres de leur famille.

COMMANDITAIRE

Société des obstétriciens et gynécologues du Canada.

RECOMMANDATIONS

Le niveau des résultats ne permet pas la formulation de recommandations factuelles.

Comprehensive study on laboratory biomarkers for prediction and diagnosis of deep venous thrombosis

Deep venous thrombosis (DVT) is based upon clinical suspicion in patients at risk and confirmatory duplex imaging of the deep venous system of the affected extremity. The aim of the present study was to determine different cutoff points of D-dimer, P-selectin and microparticles that could be used in early diagnosis and prediction of impending DVT in symptomatic patients with normal duplex ultrasound. Three groups of individuals were examined: 50 healthy volunteers (Group I); 75 patients with positive duplex ultrasound for DVT (Group II) and 75 symptomatic patients, but with negative duplex ultrasound for DVT (Group III). D-dimer was measured by immunoturbidimetric assay, P-selectin by flow cytometry and microparticles by ELISA. D-dimer, P-selectin and microparticles levels were significantly higher in Group II and III patients when compared with Group I individuals. Using receiver-operating characteristic curves, we determined that cutoff levels of 0.92 mg/l for D-dimer, 17.8% for P-selectin and 16.5 nmol/l for microparticles can accurately rule out DVT. New cutoff levels were estimated for the three studied biomarkers that differentiated the group of DVT-negative duplex patients without thrombosis from those patients of the same group who developed thrombosis being 2.81 mg/l for D-dimer, 30.2% for P-selectin and 26 nmol/l for microparticles. D-dimer, P-selectin and microparticles can be used to diagnose and detect impending DVT, thus identifying patients at high risk that could benefit from early anticoagulant therapy without the need for imaging studies.

The geko™ electro-stimulation device for venous thromboembolism prophylaxis: a NICE medical technology guidance

The geko™ device is a single-use, battery-powered, neuromuscular electrostimulation device that aims to reduce the risk of venous thromboembolism (VTE). The National Institute for Health and Care Excellence (NICE) selected the geko™ device for evaluation, and invited the manufacturer, Firstkind Ltd, to submit clinical and economic evidence. King's Technology Evaluation Centre, an External Assessment Centre (EAC) commissioned by the NICE, independently assessed the evidence submitted. The sponsor submitted evidence related to the geko™ device and, in addition, included studies of other related devices as further clinical evidence to support a link between increased blood flow and VTE prophylaxis. The EAC assessed this evidence, conducted its own systematic review and concluded that there is currently limited direct evidence that geko™ prevents VTE. The sponsor's cost model is based on the assumption that patients with an underlying VTE risk and subsequently treated with geko™ will experience a reduction in their baseline risk. The EAC assessed this cost model but questioned the validity of some model assumptions. Using the EACs revised cost model, the cost savings for geko™ prophylaxis against a 'no prophylaxis' strategy were estimated as £197 per patient. Following a second public consultation, taking into account a change in the original draft recommendations, the NICE medical technologies guidance MTG19 was issued in June 2014. This recommended the adoption of the geko™ for use in people with a high risk of VTE and when other mechanical/pharmacological methods of prophylaxis are impractical or contraindicated in selected patients within the National Health Service in England.

Update on the lower extremity venous ultrasonography examination

Lower extremity venous ultrasonography is an accurate method to diagnose acute deep venous thrombosis (DVT). Recurrent DVT is often difficult diagnosis. The decision to order ultrasonography can be based on pretest risk assessment. If the ultrasonography study is negative, the report may recommend follow-up for patients whose clinical condition changes or for patients with specific risks. Lower extremity venous ultrasonography is the gold standard for diagnosis of DVT. It is accurate and objective, and because the clinical assessment of patients is limited and its potential complication, pulmonary embolism, is significant, the impact of a positive and negative test is high.

Comparison of venous thromboembolism after total hip arthroplasty between ankylosing spondylitis and osteoarthritis

Objective. Ankylosing spondylitis (AS), an inflammatory rheumatic disease, will gradually lead to severe hip joint dysfunction. Total hip arthroplasty is a useful method to improve patients' quality of life. The aim of this study was to compare the incidence and risk factors of deep vein thrombosis (DVT) between AS and hip osteoarthritis. Methods. In a retrospective study, a total of 149 subjects who underwent cementless THA were studied. Clinical data, biochemical data, and surgery-related data were measured between AS and OA groups. Results. The incidence of DVT in AS group was lower than that of OA group, although no significant difference was detected (P = 0.89). The patients of AS group were much younger (P < 0.0001) and thinner (P = 0.018) compared with those of OA group. AS patients had higher ejection fraction (EF) (P = 0.016), higher platelet counts (P < 0.0001), and lower hypertension rate (P = 0.0004). The values of APTT, PT, and INR in AS patients were higher than those in OA patients (all P < 0.0001). The values of D-dimer and APTT were both significantly higher in DVT subjects than those in non-DVT subjects. Conclusion. AS patients potentially had a lower incidence of DVT compared with OA patients.

Tempofilter II implantation in patients with lower extremity fractures and proximal deep vein thrombosis

PURPOSE

We aimed to examine the efficacy and safety of Tempofilter II (B. Braun, Melsungen, Germany) implantation to prevent pulmonary embolism in patients with lower-extremity fractures and proximal deep vein thrombosis (DVT).

MATERIALS AND METHODS

The records of patients with lower limb fractures and proximal DVT who were implanted with Tempofilter II devices from May 2004 to August 2009 were reviewed. Data collected included success rate, occurrence of pulmonary embolism, retrieval rate, and complications.

RESULTS

A total of 176 eligible patients, including 129 males (73.3%) and 47 females (26.7%) with a median age of 42.0 years (interquartile range [IQR], 34.0-52.0 years) were included in the study. Filters were successfully implanted in 174 patients (98.9%). One patient experienced a pulmonary embolism after implantation and died. Filters were removed without complications in all other patients. Median filter implantation time was 27 days (IQR, 25.0-29.0 days). Visible organized thrombi were present on the surface of 144 (82.8%) of filters after removal, and the diameter of most thrombi (n=124) ranged from 0.5 to 1.0 cm. Filters migrated <2 cm in 104 patients (59.8%) and ≥ 2 cm in five patients (2.9%). In these five cases, three filters migrated into the right atrium and two migrated to the orifice of the renal veins.

CONCLUSION

Tempofilter II is safe and may be useful in cases of lower extremity fracture with proximal DVT for the prevention of pulmonary embolism. The filter is easily placed and retrieved, and associated with minimal complications.

Combined oral contraceptives: venous thrombosis

BACKGROUND

Combined oral contraceptive (COC) use has been associated with venous thrombosis (VT) (i.e., deep venous thrombosis and pulmonary embolism). The VT risk has been evaluated for many estrogen doses and progestagen types contained in COC but no comprehensive comparison involving commonly used COC is available.

OBJECTIVES

To provide a comprehensive overview of the risk of venous thrombosis in women using different combined oral contraceptives.

SEARCH METHODS

Electronic databases (Pubmed, Embase, Web of Science, Cochrane, CINAHL, Academic Search Premier and ScienceDirect) were searched in 22 April 2013 for eligible studies, without language restrictions.

SELECTION CRITERIA

We selected studies including healthy women taking COC with VT as outcome.

DATA COLLECTION AND ANALYSIS

The primary outcome of interest was a fatal or non-fatal first event of venous thrombosis with the main focus on deep venous thrombosis or pulmonary embolism. Publications with at least 10 events in total were eligible. The network meta-analysis was performed using an extension of frequentist random effects models for mixed multiple treatment comparisons. Unadjusted relative risks with 95% confidence intervals were reported.Two independent reviewers extracted data from selected studies.

MAIN RESULTS

3110 publications were retrieved through a search strategy; 25 publications reporting on 26 studies were included. Incidence of venous thrombosis in non-users from two included cohorts was 0.19 and 0.37 per 1 000 person years, in line with previously reported incidences of 0,16 per 1 000 person years. Use of combined oral contraceptives increased the risk of venous thrombosis compared with non-use (relative risk 3.5, 95% confidence interval 2.9 to 4.3). The relative risk of venous thrombosis for combined oral contraceptives with 30-35 μg ethinylestradiol and gestodene, desogestrel, cyproterone acetate, or drospirenone were similar and about 50-80% higher than for combined oral contraceptives with levonorgestrel. A dose related effect of ethinylestradiol was observed for gestodene, desogestrel, and levonorgestrel, with higher doses being associated with higher thrombosis risk.

AUTHORS' CONCLUSIONS

All combined oral contraceptives investigated in this analysis were associated with an increased risk of venous thrombosis. The effect size depended both on the progestogen used and the dose of ethinylestradiol. Risk of venous thrombosis for combined oral contraceptives with 30-35 μg ethinylestradiol and gestodene, desogestrel, cyproterone acetate and drospirenone were similar, and about 50-80% higher than with levonorgestrel. The combined oral contraceptive with the lowest possible dose of ethinylestradiol and good compliance should be prescribed-that is, 30 μg ethinylestradiol with levonorgestrel.

Different combined oral contraceptives and the risk of venous thrombosis: systematic review and network meta-analysis

OBJECTIVE

To provide a comprehensive overview of the risk of venous thrombosis in women using different combined oral contraceptives.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

PubMed, Embase, Web of Science, Cochrane, Cumulative Index to Nursing and Allied Health Literature, Academic Search Premier, and ScienceDirect up to 22 April 2013.

REVIEW METHODS

Observational studies that assessed the effect of combined oral contraceptives on venous thrombosis in healthy women. The primary outcome of interest was a fatal or non-fatal first event of venous thrombosis with the main focus on deep venous thrombosis or pulmonary embolism. Publications with at least 10 events in total were eligible. The network meta-analysis was performed using an extension of frequentist random effects models for mixed multiple treatment comparisons. Unadjusted relative risks with 95% confidence intervals were reported. The requirement for crude numbers did not allow adjustment for potential confounding variables.

RESULTS

3110 publications were retrieved through a search strategy; 25 publications reporting on 26 studies were included. Incidence of venous thrombosis in non-users from two included cohorts was 1.9 and 3.7 per 10,000 woman years, in line with previously reported incidences of 1-6 per 10,000 woman years. Use of combined oral contraceptives increased the risk of venous thrombosis compared with non-use (relative risk 3.5, 95% confidence interval 2.9 to 4.3). The relative risk of venous thrombosis for combined oral contraceptives with 30-35 µg ethinylestradiol and gestodene, desogestrel, cyproterone acetate, or drospirenone were similar and about 50-80% higher than for combined oral contraceptives with levonorgestrel. A dose related effect of ethinylestradiol was observed for gestodene, desogestrel, and levonorgestrel, with higher doses being associated with higher thrombosis risk.

CONCLUSION

All combined oral contraceptives investigated in this analysis were associated with an increased risk of venous thrombosis. The effect size depended both on the progestogen used and the dose of ethinylestradiol.

COPD and associated comorbidities: a review of current diagnosis and treatment

Health care utilization and costs associated with chronic obstructive pulmonary disease (COPD) continue to increase, notwithstanding evidence-based management strategies described by major respiratory societies. Cardiovascular diseases, asthma, diabetes and its precursors (obesity and metabolic syndrome), depression, cognitive impairment, and osteoporosis are examples of common comorbidities that can affect or be affected by COPD. Appropriate diagnosis and management (from a pharmacologic and nonpharmacologic perspective) of COPD and its associated comorbidities are important to ensure optimal patient care. An evolving understanding of COPD as a multimorbid disease that affects an aging population, rather than just a lung-specific disease, necessitates an integrated, tailored disease-management approach to improve prognoses and reduce costs.

Clinical characteristics and outcomes of patients with clinically unsuspected pulmonary embolism versus patients with clinically suspected pulmonary embolism

BACKGROUND

The routine use of multidetector computed tomography has led to increased detection of unsuspected pulmonary embolism (UPE), with questionable benefit for diagnosis and treatment.

OBJECTIVE

The purpose of this work was to compare the clinical characteristics and prognosis of patients with UPE to patients with suspected PE (SPE).

METHODS

We retrospectively reviewed the charts of patients diagnosed with PE in a community-based university hospital between the years 2002 and 2007. UPE was defined as PE detected on CT scans performed for indications other than suspicion of PE. We compared patients with UPE to patients with SPE for differences in clinical features, electrocardiogram, imaging and echocardiographic findings. We also assessed the long-term outcomes using electronic patient records.

RESULTS

Of 500 patients with PE, 408 had SPE and 92 had UPE. Patients with UPE were similar to patients with SPE regarding age and sex distribution. Malignancy was more prevalent in UPE patients (39 vs. 23%, p < 0.0068). UPE patients had significantly less tachypnea (37 vs. 57%, p = 0.0005), dyspnea (47 vs. 87%, p < 0.0001), chest pain (19 vs. 42%, p < 0.0001) and hypoxemia (36 vs. 55%, p = 0.0011). Mortality was higher in UPE patients (70.3 vs. 53%, p = 0.0029). The hazard ratio after adjustment for confounders including age, sex and malignancy was 1.546 (95% CI: 1.139-2.099, p = 0.0052).

CONCLUSIONS

We suggest that UPE is more prevalent in patients with a malignancy and is associated with higher mortality despite a less severe clinical presentation. UPE may be a marker of poor prognosis.

Genetic considerations for a woman's annual gynaecological examination

OBJECTIVE

To provide the physician with an overview of common genetic conditions that should be considered during a women's annual gynaecological assessment to determine the patient's risk or to initiate specific testing or referral to another subspecialty service, depending on personal or family history.

OPTIONS

This genetic information can be used for patient education and possible disease and/or mutation screening or diagnosis.

OUTCOMES

The use of this genetic information may allow improved risk-benefit assessment and management at the annual gynaecological examination.

EVIDENCE

Studies published in English up to and including May 2010 were retrieved through searches of PubMed and the Cochrane Library, using appropriate controlled vocabulary (gynaecological diagnosis, genetic inheritance) and key words (genetic risk, genetic mutation, inheritance, family history, uterus, ovary, endometrial, vagina, colon, gastric, renal, breast, cardiac, thrombophilia, diabetes, epilepsy, leiomyomata uteri). Other literature sources were identified through searching the web sites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The levels of evidence are not adequate for evidence-based recommendations to be made.

BENEFITS, HARMS, AND COSTS

This committee opinion will enhance the use of new genetic knowledge and its application to the annual gynaecological care of women. Risk management and diagnostic opportunities for genetic gynaecological conditions will be improved. A more complete understanding of genetic conditions may increase anxiety and psychological stress for women and their families.

SPONSORS

Society of Obstetricians and Gynaecologists of Canada.

RECOMMENDATIONS

The levels of evidence are not adequate for evidence-based recommendations to be made.

Critical issues in the evaluation and management of adult patients presenting to the emergency department with suspected pulmonary embolism

This clinical policy from the American College of Emergency Physicians is the revision of a 2003 clinical policy on the evaluation and management of adult patients presenting with suspected pulmonary embolism (PE).(1) A writing subcommittee reviewed the literature to derive evidence-based recommendations to help clinicians answer the following critical questions: (1) Do objective criteria provide improved risk stratification over gestalt clinical assessment in the evaluation of patients with possible PE? (2) What is the utility of the Pulmonary Embolism Rule-out Criteria (PERC) in the evaluation of patients with suspected PE? (3)What is the role of quantitative D-dimer testing in the exclusion of PE? (4) What is the role of computed tomography pulmonary angiogram of the chest as the sole diagnostic test in the exclusion of PE? (5) What is the role of venous imaging in the evaluation of patients with suspected PE? (6) What are the indications for thrombolytic therapy in patients with PE? Evidence was graded and recommendations were given based on the strength of the available data in the medical literature.

Development of diagnostic criteria for serious non-AIDS events in HIV clinical trials

PURPOSE

Serious non-AIDS (SNA) diseases are important causes of morbidity and mortality in the HAART era. We describe development of standard criteria for 12 SNA events for Endpoint Review Committee (ERC) use in START, a multicenter international HIV clinical trial.

METHODS

SNA definitions were developed based upon the following: (1) criteria from a previous trial (SMART), (2) review of published literature, (3) an iterative consultation and review process with the ERC and other content experts, and (4) evaluation of draft SNA criteria using retrospectively collected reports in another trial (ESPRIT).

RESULTS

Final criteria are presented for acute myocardial infarction, congestive heart failure, coronary artery disease requiring drug treatment, coronary revascularization, decompensated liver disease, deep vein thrombosis, diabetes mellitus, end-stage renal disease, non-AIDS cancer, peripheral arterial disease, pulmonary embolism, and stroke. Of 563 potential SNA events reported in ESPRIT and reviewed by an ERC, 72% met "confirmed" and 13% "probable" criteria. Twenty-eight percent of cases initially reviewed by the ERC required follow-up discussion (adjudication) before a final decision was reached.

CONCLUSION

HIV clinical trials that include SNA diseases as clinical outcomes should have standardized SNA definitions to optimize event reporting and validation and should have review by an experienced ERC with opportunities for adjudication.

Acute pulmonary embolism. Part 1: epidemiology and diagnosis

Pulmonary embolism (PE) is a frequently occurring, acute, and potentially fatal condition. Numerous risk factors for PE, both inherited and acquired, have been identified. Adequate diagnosis is mandatory to prevent PE-related morbidity and mortality on the one hand, and unnecessary treatment on the other. Only around 1 in 5 individuals with suspected PE will have the diagnosis confirmed, therefore, the diagnostic work-up for PE should comprise safe, efficient, and noninvasive methods. The first step in the approach to diagnosis of patients with suspected PE is to determine the clinical probability and to perform a D-dimer test. PE can be excluded in patients with a 'low', 'intermediate' or 'unlikely' clinical probability and a normal D-dimer test. Additional imaging is required for those with a 'high' or 'likely' clinical probability or a positive D-dimer test. CT pulmonary angiography or ventilation-perfusion scintigraphy, followed by additional testing is the next step when test results are nondiagnostic. Although various diagnostic strategies have been introduced and validated, selected patients may require a tailored approach.

Catheter-directed thrombolysis of lower limb thrombosis

Late complications of thrombosis of the deep veins in the region between the popliteal vein termination and the confluence of the common iliac veins and inferior vena cava (suprapopliteal deep-vein thrombosis) are common and often unrecognized by those responsible for the initial management. Pharmacomechanical-assisted clearance of the thrombus at the time of first presentation provides the best opportunity for complete recovery with preservation of normal venous valve function and avoidance of recurrent deep-vein thrombosis and postthrombotic syndrome. Recent interventional radiology methods provide for rapid and complete thrombolysis even in some patients in whom thrombolysis was previously considered contraindicated. This review describes the methods, safety, and efficacy of acute interventional treatment of suprapopliteal deep-vein thrombosis.

Venous thromboembolism: a clinical review

Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism, represents a significant source of morbidity and mortality. It is readily diagnosed with noninvasive modalities when there is a clinical suspicion. Most patients presenting with signs and symptoms of DVT have well-known risk factors, such as a history of VTE, malignancy, recent illness, or immobilization. A subset of individuals with idiopathic VTE have no readily identifiable risk factors. Therapeutic anticoagulation is the cornerstone of management in all patients with VTE. Adjunctive measures, such as thrombolysis and the use of vena cava filters, are indicated in select cases. The ideal duration of anticoagulation is unknown, but is often maintained long-term in patients with acquired or inherited thrombophilia. Warfarin is the only oral anticoagulant approved by the US Food and Drug Administration. Warfarin carries a substantial annual risk of bleeding complications, requires ongoing monitoring, and has extensive drug-drug interactions, which are causes for concern in patients requiring long-term anticoagulation. Alternative oral anticoagulants, such as direct thrombin inhibitors and factor Xa inhibitors, are subjects of active research in alternative agents for oral anticoagulation, and have been recently approved for prophylaxis in Canada and the European Union.

An algorithm for the diagnosis and management of chest pain in primary care

This article focuses on the key clinical and investigatory features that help differentiate the multiple causes of chest pain in adults in assessment of patients with undifferentiated chest pain in primary care using history, physical examination, and basic initial investigations. The initial treatment of many of the causes is discussed. Some treatments not only relieve symptoms but also provide further diagnostic information based on the response to treatment. Guidance for referral for specialist assessment and further investigations is provided, but the diagnostic usefulness of these measures is not discussed.

Strategies for managing imaging utilization

Imaging represents a substantial and growing portion of the costs of American health care. When performed correctly and for the right reasons, medical imaging facilitates quality medical care that brings value to both patients and payers. When used incorrectly because of inappropriate economic incentives, unnecessary patient demands, or provider concerns for medical-legal risk, imaging costs can increase without increasing diagnostic yields. A number of methods have been tried to manage imaging utilization and achieve the best medical outcomes for patients without incurring unnecessary costs. The best method should combine a prospective approach; be transparent, evidence based, and unobtrusive to the doctor-patient relationship and provide for education and continuous quality improvement. Combining the proper utilization of imaging and its inherent cost reduction, with improved quality through credentialing and accreditation, achieves the highest value and simultaneous best outcomes for patients.

Underutilization of evidence-based strategies in the diagnosis and treatment of venous thromboembolism among trainees

BACKGROUND

The knowledge and attitude of trainees toward the use of prediction rules in the diagnosis of venous thromboembolism (VTE) is understudied. The extent of knowledge as far as imaging strategies in the setting of VTE and use of low molecular weight heparin (LMWH) among trainees is also understudied.

METHODS

This was a cross-sectional study; between October, 2006 and March, 2008, surveys were distributed at grand rounds and national medicine board review courses. Respondents returning completed surveys included 43 medicine attendings, 139 residents, and 134 medical students Emergency physicians were called at work and 46 completed an abbreviated version of the survey. Attending and trainee responses were compared.

RESULTS

Over 60% of students and 40% of residents did not use any prediction rules. Most attendings (>60%) did not use a prediction rule. Among attendings, 48% of emergency physicians and 30% of medicine attendings felt that prediction rules were too complex to use. Knowledge about imaging techniques and diagnostic protocols for VTE were worse for students than for residents. A substantial minority of all respondents (17% of students, 12% of residents and 13% of medicine attendings) would not use LMWH in the therapy of non-massive pulmonary embolism. In general, level of training did not translate into a greater proportion of correct responses to clinical scenarios or greater knowledge about imaging systems and strategies.

CONCLUSION

Trainees do not use a structured approach to VTE diagnosis. LMWH therapy is underutilized by a large minority of trainees and attendings. A top-down approach is needed to revitalize evidence-based management of VTE.

Clinical conditions and patient factors significantly influence diagnostic utility of D-dimer in venous thromboembolism

Determining D-dimer levels remains important in the diagnostic algorithms for venous thromboembolism (VTE). The present study aimed to identify factors influencing D-dimer utility in diagnosing VTE. Consecutive symptomatic medical patients, who attended our emergency department from 1 November 2006 to 31 December 2006, had D-dimer levels measured as fibrinogen equivalent units (FEU), following clinical risk assessment. Diagnosis of VTE was established by venous compression ultrasonography and computed tomographic pulmonary angiography. VTE-negative patients were followed for 2 months to detect future occurrence of thromboembolism. Impact of various factors on D-dimer levels was analyzed. Four thousand and twenty-six patients attended our emergency department, and 525 patients (median age 52 years) had D-dimer assessed. Final diagnosis of VTE was established in 25 (4.7%) patients on radiological investigations. Median D-dimer levels for VTE-negative patients less than 60 years old, with normal renal function and chest radiology were 0.38 microgFEU/ml (range 0.19-2.3), 0.39 microgFEU/ml (range 0.17-3.5) and 0.39 microgFEU/ml (range 0.1-4.3), respectively. Similar figures for those at least 60 years, with renal impairment and abnormal chest radiology, were 0.75 microgFEU/ml (range 0.22-4.3), 0.52 microgFEU/ml (range 0.17-4.4) and 0.92 microgFEU/ml (range 0.26-5.6), respectively. Factors including patient age, renal function and chest radiology had significant influence on D-dimer levels (P < 0.01). A triad of patient age at least 60 years, renal impairment (modification of diet in renal disease stage 2-5) and abnormal chest radiology had a false positive D-dimer in 96% of patients (n = 72). Use of D-dimer in patients with a triad of advanced age, renal impairment and abnormal chest radiology has no practical diagnostic value in VTE.