Suman Rathbun

Sensitivity and Specificity of Helical Computed Tomography in the Diagnosis of Pulmonary Embolism: A Systematic Review

Pulmonary embolism is a major health problem in the United States. The estimated annual incidence is 69 cases per 100 000 persons (1), which means that more than 175 000 persons develop established pulmonary embolism each year. Prospective studies have documented a 30% to 40% prevalence of pulmonary embolism in patients who have clinical features of suspected pulmonary embolism (2-4). Therefore, clinically suspected pulmonary embolism is present in more than 575 000 persons in the United States each year. It is difficult to diagnose pulmonary embolism because the clinical diagnosis is nonspecific (2-8) and all of the objective tests have clinical or practical limitations (2-6). The ventilation-perfusion lung scan has been the first-line test for more than 20 years. However, 60% to 70% of lung scans are nondiagnostic (2-4), and combining clinical assessment with lung scan results or using a clinical algorithm fails to identify 20% of patients with pulmonary embolism (3, 4, 8). Pulmonary angiography is the gold standard (9-12), but it is invasive and expensive, may be impractical or unavailable in some clinical settings, and causes cardiac or pulmonary complications in 3% to 4% of patients (12, 13). Objective testing for deep venous thrombosis is useful if the results are positive (4-6, 14), but negative results do not exclude pulmonary embolism (4-6, 11, 14, 15). Serial testing for proximal deep venous thrombosis can be used as an alternative to pulmonary angiography in selected patients, such as those with adequate cardiorespiratory reserve or a low or moderate suspicion of pulmonary embolism (14, 16, 17). The d-dimer assay is promising as an exclusion test, but a positive result is nonspecific and occurs in 40% to 69% of patients (18, 19). Therefore, definitive testing for the presence or absence of pulmonary embolism is required for many patients, such as those with severe underlying cardiopulmonary disease and inadequate cardiorespiratory reserve (5, 6, 17, 20). Recently, interest has developed in using helical computed tomography (CT), also known as spiral CT, for the diagnosis of pulmonary embolism (21-23). Helical CT scanning produces a volumetric two-dimensional image of the lung by rotating the detector around the patient. Total acquisition time is less than 30 seconds. Pulmonary embolism appears as a filling defect that may be central, eccentric, or mural and may partially or totally occlude the vessel. Helical CT is minimally invasive and can help identify other disorders that may be responsible for the patients symptoms. However, it is expensive to perform and interpret; it requires that a contrast agent be intravenously injected; and it is often difficult or impossible to perform in patients who require ventilation, are hemodynamically unstable, or cannot cooperate. Some researchers have recommended helical CT as a first-line replacement for lung scans and pulmonary angiography (23-25), and others have suggested that diagnostic algorithms based on helical CT be used in selected patients (24, 26, 27). Several experts have called for more research (24-26, 28). Because of the debate about the role of helical CT in the diagnosis of pulmonary embolism (29), we performed a systematic review of the literature (30). Our review had two objectives: to determine the sensitivity and specificity of helical CT for the diagnosis of pulmonary embolism in symptomatic patients, and to determine the safety of withholding anticoagulant therapy without further objective testing for venous thromboembolism in patients who have clinically suspected pulmonary embolism and negative results on helical CT. Methods Literature Search and Data Sources We searched the MEDLINE database for literature published from 1986 through November 1999. The MeSH terms pulmonary embolism and tomography, x-ray computed were used in separate searches, and studies found during each search were combined. Limits were set for human only and English language only. We supplemented this reference list by cross-checking bibliographies of retrieved articles to identify additional studies. Study Selection and Data Extraction Before performing the literature review, we defined criteria for inclusion of studies and for assessing the validity of these studies (31). We decided a priori to include all prospective studies identified by the literature search, including abstracts. Retrospective studies, review articles, and case reports were excluded. Two of the authors reviewed each article or abstract independently using the criteria outlined in Table 1. These criteria were established a priori before the articles were reviewed, according to established methodologic standards for evaluation of diagnostic tests (32, 33). Different criteria were used to assess studies that evaluated the sensitivity and specificity of helical CT for diagnosis of pulmonary embolism and studies that evaluated the safety of withholding anticoagulant therapy in patients with negative results on helical CT. A third independent reviewer resolved disagreements by adjudication. Table 1. Criteria Used To Appraise Prospective Studies Identified by Literature Search Data Synthesis Literature Search and Data Sources The literature search identified 20 articles (34-53) and 6 abstracts (54-59). Five articles were excluded; 4 were retrospective studies (49-52), and 1 was a series of case reports (53). The abstracts were excluded from further analysis because they reported the results of subsequent articles or contained insufficient information for evaluation of study validity. Fifteen original prospective studies (34-48) were assessed by using the criteria in Table 1. Of these 15 studies, 13 were unique. Two studies by van Rossum and colleagues (38, 40) included some of the same patients (van Rossum AB. Personal communication). These studies evaluated 249 and 149 patients, respectively (38, 40) (Table 2). Study Appraisal Table 2 summarizes the results of our assessment of the 15 prospective studies. Only 2 studies (36, 38) explicitly stated that a consecutive series of all patients with suspected pulmonary embolism was evaluated. In 8 studies, helical CT and pulmonary angiography were interpreted independently (34-37, 39, 41, 43, 46). Only 1 study (34) included enough data to allow us to conclude that a broad spectrum of patients had been evaluated. Thirteen articles included a description of the size of the vessels imaged by helical CT (34-39, 41, 43-48). Six studies described the size of the pulmonary embolism on angiography (34, 37, 40, 41, 44, 47). Table 2. Prospective Studies Evaluating the Use of Helical Computed Tomography in the Diagnosis of Suspected Pulmonary Embolism Sensitivity and Specificity The reported sensitivity of helical CT ranged from 53% to 100%, and the reported specificity ranged from 81% to 100% (Table 2). Only four articles reported 95% CIs (40, 41, 44, 46). Safety of Withholding Anticoagulant Therapy No prospective study was identified in which anticoagulant therapy was withheld without additional testing for venous thromboembolism in consecutive patients who had suspected pulmonary embolism and negative results on helical CT. One study prospectively followed up selected patients who had suspected pulmonary embolism and negative results on helical CT (44). Patients were eligible if they had an intermediate-probability ventilation-perfusion lung scan and negative results on duplex ultrasonography of the legs. Computed tomography yielded positive results in 39 of 164 patients and negative results in 125 of 164 patients. Pulmonary angiography was performed in 15 of these 125 patients and showed pulmonary embolism in 1 patient. All 15 patients were treated with anticoagulant therapy. A total of 109 patients with negative results on helical CT did not receive anticoagulant therapy and were followed for 3 months. Fatal pulmonary embolism was strongly suspected in 1 patient who died 10 days after study entry. In addition, high-probability ventilation-perfusion lung scans documented symptomatic pulmonary embolism in 2 patients at 2 months and 3 months of follow-up (44). Discussion We sought to determine the sensitivity and specificity of helical CT for the diagnosis of pulmonary embolism and the safety of withholding anticoagulant therapy in patients with negative results on helical CT. Our results support four major inferences. First, none of the studies met all of the methodologic criteria for adequately evaluating the sensitivity and specificity of a diagnostic test (32, 33). Several studies were missing key data on the methods used to select patients, whether helical CT and the reference test were interpreted independently, and whether the study sample included a broad spectrum of patients with suspected pulmonary embolism. Details were often missing on the clinical features of patients at presentation, the size of pulmonary embolism on angiography, and the presence or absence of comorbid conditions that may have confused the diagnosis. All studies to date have included relatively few patients who underwent both helical CT and an appropriate reference test. Second, a wide range of sensitivity (53% to 100%) was reported for helical CT (Table 2). Two recent studies reported sensitivities of 60% and 67% (46, 47), and in one of these studies (47) all cases of pulmonary embolism documented by pulmonary angiography involved segmental or lobar arteries. The wide range of sensitivity among these studies may be due to differences in patient selection, extent of pulmonary embolism, technology and testing methods (including pitch, collimator thickness, and the concentration of the contrast agent), methods of interpretation (workstations or hard copy, windowing of images), reader experience, and interobserver variation. Third, our results suggest that interobserver variation is a potentially important limitation of helical CT. Three studies reported interobserver variation in the s

The Surgeon General’s Call to Action to Prevent Deep Vein Thrombosis and Pulmonary Embolism

On September 15, 2008, the US Surgeon General, Rear Admiral Steven K. Galson, MD, MPH, issued the first Call to Action to Prevent Deep Vein Thrombosis and Pulmonary Embolism.1 What is a “call to action” and why should we heed the recommendations of the highest ranking physician in the nation? A call to action is a science-based document to stimulate action nationwide to solve a major public health problem. Over the years, the Surgeon General has issued several calls to action. The first and most important document was the Report on Smoking and Health issued in 1964.2 This warning about the health risks of cigarettes was issued by the Surgeon General at a time when smoking was common and fashionable. It caught the attention of the general public and set the groundwork for the subsequent 40 years of research and awareness that resulted in the lowest smoking rates in history. Now, 44 years later, the alarm has been sounded on another equally disabling and deadly disease, deep-vein thrombosis (DVT) and pulmonary embolism, collectively known as venous thromboembolism (VTE). DVT refers to blood clots forming most commonly in the deep veins of the legs that can break off and travel to the heart, ultimately lodging in the arteries of the lungs, a condition known as pulmonary embolism, causing death and disability. Healthcare providers have recognized for many years that VTE may occur in their …

Compression stockings to prevent post-thrombotic syndrome: a randomised placebo-controlled trial.

BACKGROUND Post-thrombotic syndrome (PTS) is a common and burdensome complication of deep venous thrombosis (DVT). Previous trials suggesting benefit of elastic compression stockings (ECS) to prevent PTS were small, single-centre studies without placebo control. We aimed to assess the efficacy of ECS, compared with placebo stockings, for the prevention of PTS. METHODS We did a multicentre randomised placebo-controlled trial of active versus placebo ECS used for 2 years to prevent PTS after a first proximal DVT in centres in Canada and the USA. Patients were randomly assigned to study groups with a web-based randomisation system. Patients presenting with a first symptomatic, proximal DVT were potentially eligible to participate. They were excluded if the use of compression stockings was contraindicated, they had an expected lifespan of less than 6 months, geographical inaccessibility precluded return for follow-up visits, they were unable to apply stockings, or they received thrombolytic therapy for the initial treatment of acute DVT. The primary outcome was PTS diagnosed at 6 months or later using Ginsbergs criteria (leg pain and swelling of ≥1 month duration). We used a modified intention to treat Cox regression analysis, supplemented by a prespecified per-protocol analysis of patients who reported frequent use of their allocated treatment. This study is registered with ClinicalTrials.gov, number NCT00143598, and Current Controlled Trials, number ISRCTN71334751. FINDINGS From 2004 to 2010, 410 patients were randomly assigned to receive active ECS and 396 placebo ECS. The cumulative incidence of PTS was 14·2% in active ECS versus 12·7% in placebo ECS (hazard ratio adjusted for centre 1·13, 95% CI 0·73-1·76; p=0·58). Results were similar in a prespecified per-protocol analysis of patients who reported frequent use of stockings. INTERPRETATION ECS did not prevent PTS after a first proximal DVT, hence our findings do not support routine wearing of ECS after DVT. FUNDING Canadian Institutes of Health Research.

Negative d-dimer Result To Exclude Recurrent Deep Venous Thrombosis: A Management Trial

Context Acute recurrent deep venous thrombosis (DVT) is often difficult to differentiate from post-thrombotic syndrome, and each of the established diagnostic methods has limitations. A reliable test that excludes the diagnosis would be clinically useful. Contribution Patients with suspected recurrent DVT underwent d-dimer testing. Heparin was withheld or withdrawn in patients with negative results, and no additional testing was performed, regardless of symptoms. Three-month follow-up showed a low incidence (0.75% [95% CI, 0.02% to 4.09%]) of confirmed DVT in patients with a negative d-dimer result. Implications d-dimer testing may obviate the need to perform additional testing in up to two thirds of patients being evaluated for recurrent DVT. The Editors Deep venous thrombosis is a common condition that affects more than 250000 patients each year in the United States (1, 2). Symptoms of recurrent DVT, including leg pain or swelling, occur in one third of affected patients despite adequate anticoagulant treatment (3). Clinical diagnosis is inaccurate for distinguishing new, recurrent DVT from the post-thrombotic syndrome or other causes of leg pain and swelling. Diagnostic testing is needed because two thirds of patients with a clinical suspicion of recurrent DVT are shown to be free of acute thrombosis (4). Acute recurrent DVT is confirmed by 1) the finding of a new noncompressible vein segment on compression ultrasonography, 2) a newly abnormal impedance plethysmography result, or 3) the finding of a new intraluminal filling defect on venography (3-5). However, all of the available diagnostic tests have limitations for excluding acute recurrent DVT. The results of compression ultrasonography may be persistently abnormal for 1 year in 50% of patients and longer in others (6-8). The combined use of impedance plethysmography and radiofibrinogen leg scanning has been useful for excluding recurrent DVT (4, 9). However, impedance plethysmography is no longer available, and I125 fibrinogen leg scanning is no longer used because of concern about potential viral transmission associated with fibrinogen injection. Venography also has limitations for excluding the diagnosis of recurrent DVT due to obliteration and recanalization of the previously affected venous segment or nonfilled venous segments (5). Nuclear venous imaging with technetium-labeled platelet glycoprotein IIb/IIIa receptor antagonists is a promising approach, but it has substantial limitations related to observer variation (10). Therefore, nuclear venous imaging requires additional evaluation before it is recommended. Because of the limitations of the available diagnostic tests for DVT, there has been interest in the use of the laboratory assay for plasma d-dimer as an exclusion test. Automated rapid quantitative tests for detecting d-dimer in plasma have recently become available. Studies in patients with a suspected first episode of venous thromboembolism have shown that some of these assays have high sensitivity for acute DVT or pulmonary embolism (11). d-dimer has been used safely as an exclusion test in patients presenting with their first episode of DVT (12-14). The sensitivity of the STA-Liatest d-di (Diagnostica Stago, Asnieres-sur-Seine, France, and Parsippany, New Jersey) has been reported to be 96% to 100% in patients with suspected first-episode DVT or symptomatic pulmonary embolism (15, 16). However, the safety of using d-dimer as an exclusion test in patients with suspected recurrent DVT is uncertain. If d-dimer could be safely used to exclude acute recurrent DVT, an important unmet clinical need would be fulfilled. We performed a prospective cohort study of patients with clinically suspected recurrent DVT. The objective was to test the safety of withholding anticoagulant treatment and additional diagnostic testing in patients who have a negative d-dimer result at presentation. Because all of the standard diagnostic tests have limitations for the diagnosis of recurrent DVT, we defined criteria for the presence or absence of recurrent DVT a priori and then used long-term follow-up to test the validity of negative d-dimer results. Methods Patients and Study Protocol We conducted the study at the University of Oklahoma Health Sciences Center teaching hospitals, the Oklahoma University Medical Center, and the Veterans Affairs Medical Center. The Institutional Review Board of the University of Oklahoma Health Sciences Center approved the study. We selected consecutive patients with a history of DVT confirmed by diagnostic testing. Patients were eligible for the study if they presented with symptoms and signs of recurrent DVT in either leg and if they were referred by their physician to the vascular clinic or the noninvasive vascular testing laboratory. The study sample included inpatients and outpatients. Reasons for ineligibility were as follows: 1) signs and symptoms of upper-extremity DVT, 2) a history of pelvic venous thrombosis, 3) recent pelvic surgery, 4) an indwelling central line (upper extremity or femoral), 5) current pregnancy or delivery less than 1 month previously, 6) inability to undergo compression ultrasonography because of physical or technical limitations, or 7) inability to return for follow-up testing or visits. Patients receiving warfarin therapy or those receiving less than 24 hours of heparin or low-molecular-weight heparin therapy were eligible for the study. All eligible patients who gave informed consent underwent d-dimer testing using the STA-Liatest d-di. The automated plasma d-dimer assay was performed by using an STA Compact Diagnostica Stago assay instrument (Diagnostica Stago). A negative d-dimer result was defined before the study as a plasma concentration of 0.47 g/mL or less, as recommended by the manufacturer. All patients were then managed according to the study protocol (Figure). All patients with negative d-dimer test results had unfractionated heparin and low-molecular-weight heparin withheld or withdrawn, regardless of their symptoms. No additional diagnostic testing for DVT was performed as part of this initial evaluation for recurrent DVT in this group of patients (negative cohort). Figure. Study protocol for patients with suspected recurrent deep venous thrombosis ( DVT ). We performed compression ultrasonography in all patients with positive d-dimer test results. This was accomplished by using vein compression and measurement of residual vein diameter beginning at the common femoral vein above the inguinal ligament and moving distally at 1-cm intervals to the trifurcation in the calf. Ultrasonography results were classified as normal if all imaged segments were fully compressible (6, 17). We diagnosed new DVT by the presence of either a new noncompressible venous segment or an increase in vein diameter of greater than 4 mm (compared with the most recent previous ultrasonography result) (17). A registered vascular technologist performed the ultrasonography, and 1 of 2 internists specializing in vascular medicine interpreted the results. These individuals had knowledge of the previous ultrasonography result, if available, and the clinical presentation. Long-Term Follow-up We instructed all patients to immediately contact us or go to the emergency department if they had new symptoms or signs of venous thrombosis or pulmonary embolism. Patients were routinely assessed in the clinic or by telephone at 3 months. At this follow-up contact, a history was taken of the interval since study entry. Issues addressed were general health, specific symptoms of venous thromboembolism (including leg pain, tenderness and swelling, chest pain, dyspnea, and hemoptysis), hospitalization, and the use of anticoagulants. All patients who returned during follow-up with clinically suspected venous thrombosis or pulmonary embolism underwent diagnostic testing. For suspected DVT, compression ultrasonography, impedance plethysmography, or venography was used. For suspected pulmonary embolism, lung scanning, helical computed tomography, or pulmonary angiography was used. The physician seeing the patient selected the diagnostic tests on the basis of clinical presentation and local availability. The primary outcome measure was a diagnosis of new symptomatic venous thromboembolism, either DVT or pulmonary embolism, confirmed by diagnostic testing during the 3-month follow-up. All patients who fulfilled at least 1 of the diagnostic criteria for DVT or pulmonary embolism were considered to have confirmed venous thromboembolism on follow-up. The 3-month follow-up period was chosen because inadequate management of acute DVT results in a high rate of recurrent venous thromboembolic events during the subsequent 3 months (18-20). The diagnostic criteria used to confirm or exclude the presence of new DVT or pulmonary embolism on follow-up were defined before the study. The diagnostic criteria used to confirm DVT on follow-up were any one of the following: a new noncompressible segment identified by compression ultrasonography (5, 6, 17), a new constant intraluminal filling defect identified by venography (4), or a newly abnormal impedance plethysmography result (4, 9). Ultrasonography was classified as inconclusive if there was persistent noncompressibility in the same vein segments as the most recent previous ultrasonography result. The diagnostic criteria used to confirm pulmonary embolism on follow-up were any one of the following: a new high-probability ventilationperfusion lung scan (a perfusion defect >75% of a segment with ventilation mismatch or in an area of normal findings on chest radiography) (21), a positive helical computed tomography scan (22), a pulmonary angiogram showing a constant intraluminal filling defect (21), or pulmonary embolism found at autopsy. The diagnostic criteria used to exclude a diagnosis of DVT on follow-up were any of the following: a normal result on compression ultrasonography (that is, all veins full

Graduated compression stockings to treat acute leg pain associated with proximal DVT. A randomised controlled trial.

Acute deep venous thrombosis (DVT) causes leg pain. Elastic compression stockings (ECS) have potential to relieve DVT-related leg pain by diminishing the diameter of distended veins and increasing venous blood flow. It was our objective to determine whether ECS reduce leg pain in patients with acute DVT. We performed a secondary analysis of the SOX Trial, a multicentre randomised placebo controlled trial of active ECS versus placebo ECS to prevent the post-thrombotic syndrome.The study was performed in 24 hospital centres in Canada and the U.S. and included 803 patients with a first episode of acute proximal DVT. Patients were randomised to receive active ECS (knee length, 30-40 mm Hg graduated pressure) or placebo ECS (manufactured to look identical to active ECS, but lacking therapeutic compression). Study outcome was leg pain severity assessed on an 11-point numerical pain rating scale (0, no pain; 10, worst possible pain) at baseline, 14, 30 and 60 days after randomisation. Mean age was 55 years and 60% were male. In active ECS patients (n=409), mean (SD) pain severity at baseline and at 60 days were 5.18 (3.29) and 1.39 (2.19), respectively, and in placebo ECS patients (n=394) were 5.38 (3.29) and 1.13 (1.86), respectively. There were no significant differences in pain scores between groups at any assessment point, and no evidence for subgroup interaction by age, sex or anatomical extent of DVT. Results were similar in an analysis restricted to patients who reported wearing stockings every day. In conclusion, ECS do not reduce leg pain in patients with acute proximal DVT.

Efficacy and safety of endovenous foam sclerotherapy: meta-analysis for treatment of venous disorders

Aim Endovenous foam sclerotherapy (EFS) is used widely throughout the USA for the treatment of venous disorders. The purpose of the quantitative meta-analysis was to systematically and comprehensively evaluate the literature to provide accurate estimates of safety and efficacy outcomes for this procedure. Methods A comprehensive electronic search of published literature in several databases was performed using a wide variety of MESH headings. In addition, meeting abstracts and bibliographies of selected references were reviewed for eligible papers. Two reviewers abstracted selected treatment-related data. Results Of 684 identified manuscripts and abstracts reviewed, 104 papers were abstracted and analysed. More than 50% were published between 2004 and 2008. EFS was found to be effective with similar vein occlusion rates to laser therapy, but less effective than surgery. In addition, major adverse effects were rare. Conclusions EFS is a safe and effective therapy for the treatment of venous disorders.

Inflammation markers and their trajectories after deep vein thrombosis in relation to risk of post-thrombotic syndrome

Post‐thrombotic syndrome (PTS) is a frequent chronic complication of deep vein thrombosis (DVT).

Comparison of methods to determine rivaroxaban anti-factor Xa activity.

BACKGROUND AND OBJECTIVES Rivaroxaban, a new oral anti-Xa agent, has been approved for use without routine monitoring, but the lack of a predictable drug level measurement may hinder the management of anticoagulated patients. The aims of the project were to correlate a Anti-Factor Xa assay using commercial calibrators and controls (Riva Activity) with serum drug levels analyzed by HPLC-MS/MS (Riva MS) in patients currently receiving rivaroxaban, and secondly, to correlate the PT/PTT, thrombin generation (CAT assay) and Thromboelastograph (TEG) with the Riva activity and Riva MS. METHODS Recruited patients receiving rivaroxaban prospectively had a total of 3 blood samples taken at least 2 hours apart. Plasma was divided for measurement of PT/PTT, Riva activity, rivaroxaban HPCL-MS/MS, and thrombin generation. TEG activity was measured at one random time point for each patient. Correlation and linear regression evaluations were used to compare the different assays. RESULTS The cases were 22 patients on rivaroxaban, age 56+12.6, and 10 healthy controls. There was a strong correlation between Riva activity compared to serum Riva MS (r=0.99). We found a statistically significant correlation between PT/INR compared to serum measurements of Riva MS (r=0.68) and anti-Xa activity (r=0.69). The peak (r=-0.50) and lag time (r=0.57) CAT correlated with Riva MS measurements. There was no correlation between Riva MS and PTT, TEG R, TEG MA, Endogenous Thrombin potential. CONCLUSION Riva anti-factor Xa activity assay measured with commercial calibrators and controls provides a reliable assessment of rivaroxaban serum levels for patients requiring measurement of anticoagulant activity. Correlation with other coagulation tests is not sufficiently strong to be used clinically.

A randomized trial of dalteparin compared with ibuprofen for the treatment of superficial thrombophlebitis

Background: Superficial thrombophlebitis can produce pain and result in a deep vein thrombosis (DVT) if not treated. Conservative therapies including prescription of non‐steroidal anti‐inflammatory drugs (NSAID) and heat have been standard care. Recently, studies have been published reporting efficacy and safety of low‐molecular‐weight heparin for the treatment of superficial thrombophlebitis. However, there are few comparative trials to conservative therapy. We studied the effectiveness and safety of treatment with dalteparin compared with ibuprofen in patients with confirmed superficial thrombophlebitis. Methods: Consecutive patients were randomized to receive daily dalteparin vs. ibuprofen three times daily for up to 14 days. The primary outcome measure was the incidence of extension of thrombus or new symptomatic venous thromboembolism during the 14‐day and 3‐month follow‐up period. The secondary outcome was a reduction in pain. The outcome measure of safety was the incidence of major and minor bleeding. Results: Of 302 consecutive patients screened, 72 were enrolled. Four patients receiving ibuprofen compared with no patients receiving dalteparin had thrombus extension at 14 days (P = 0.05), however, there was no difference in thrombus extension at 3 months. Both treatments significantly reduced pain. There were no episodes of major or minor bleeding during the treatment period. Conclusions: Dalteparin is superior to the NSAID ibuprofen in preventing extension of superficial thrombophlebitis during the 14‐day treatment period with similar relief of pain and no increase in bleeding. However, questions concerning the optimal treatment duration should be explored in future trials.

Effectiveness of foam sclerotherapy for the treatment of varicose veins

Varicose veins (VVs) are associated with lifestyle-limiting symptoms and complications. Patients who fail compression therapy are candidates for more invasive treatments. This study evaluates the efficacy and safety of endovenous foam sclerotherapy (EFS) for the treatment of VVs in a US academic center. We reviewed medical records of a consecutive cohort of patients who underwent EFS over a 2-year period. The primary outcome measure was obliteration of VVs. The secondary outcome measures were symptomatic improvement, ulcer healing, recurrence, and adverse events. A total of 166 patients (217 legs) underwent EFS for pain (81%), pruritis (41%), swelling (17%), ulcerations (17%), thrombophlebitis (14%), and varix rupture (3%). Complete (65%) or near-complete (34%) obliteration was achieved in 215 (99%) legs after one injection. Additional injections achieved complete obliteration in 39 of 53 legs. Ninety-three percent (27/29) of active ulcers healed or were decreasing in size. Five ulcers and 11 VVs recurred. Common adverse events included pain and hyperpigmentation. Thrombosis, hematoma, skin necrosis, and neurologic events were rare. In conclusion, EFS appears to be a safe and effective outpatient therapy for the treatment of symptomatic and complicated VVs.