Venous Thromboembolism

The study is designed to evaluate the short-term and long-term clinical performance and safety of the Symphony and Prodigy thrombectomy systems used in endovascular procedures across the peripheral or pulmonary vasculature.

This is an observational study in which only data are collected from participants receiving their usual treatment. The study is done in children under 2 years old with venous thromboembolism (VTE). VTE is a condition in which blood clots form in the veins, usually in the leg. This can cause pain and swelling. The clot can also break apart and travel in the blood to the lungs where it can block the blood flow. This can be life threatening. Rivaroxaban is approved for doctors to prescribe to children with VTE, but there is limited information about how it is used, how well it works, and how safe it is in children under 2 years old. Children in this study are already receiving or will receive rivaroxaban or other currently used medicines for VTE from their doctor according to the approved product information. The purpose of this study is to collect information on the pattern of use and safety of rivaroxaban and other standard medicines for VTE in children under 2 years old. The main information that researchers will collect in this study: * Age, gender, and other information about the child and their illness * Type of VTE treatment given to the child * Occurrence of medically important bleeding and its severity Further information that researchers will collect: * Changes in the characteristics of the children given VTE treatment (e.g., changes in the age range of children given VTE treatment) and changes in the treatment pattern for VTE * Return of VTE symptoms * Types of doctors who prescribe VTE treatment and their set-up (e.g., special clinics versus hospitals) Besides this data collection, no further tests or examinations are needed in this study. The data for this study will be collected from electronic health records and health insurance claims data until 2026. Researchers will observe each child during treatment until: * end of the anticoagulation treatment period e.g. discontinuation of all study drugs, * their information is no longer available, or * the study ends.

Hospitalized medical patients have an increased risk of venous thromboembolism (VTE) across the continuum of care, including after hospital discharge. In the APEX Trial of hospitalized patients with acute medical illness, extended-duration post-discharge thromboprophylaxis with oral betrixaban reduced the frequency of asymptomatic proximal deep venous thrombosis (DVT), symptomatic proximal or distal DVT, symptomatic nonfatal pulmonary embolism (PE), or VTE-related death compared with short-duration enoxaparin. Obstacles to integration of these data in the hospitalized Medical Service patient population, including failure to identify at-risk patients, educational gaps in strategies for VTE prevention after discharge, and medication nonadherence, can be overcome with alert-based computerized decision support. This study is a single-center, 400-patient, randomized controlled trial of an EPIC Best Practice Advisory (BPA; alert-based computerized decision support tool) to increase prescription of extended-duration post-discharge thromboprophylaxis and decrease symptomatic VTE in high-risk patients hospitalized with medical illness. Specific Aim #1: To determine the impact of electronic alert-based CDS (EPIC Best Practice Advisory \[BPA\]) on prescription of extended-duration post-discharge thromboprophylaxis in high-risk patients hospitalized with medical illness who are not being prescribed any prophylactic anticoagulation for VTE prevention after discharge. Specific Aim #2: To estimate the impact of electronic alert-based CDS (EPIC BPA) on the frequency of symptomatic VTE in high-risk patients hospitalized with medical illness who are not being prescribed any prophylactic anticoagulation for VTE prevention after discharge.

This prospective, multicenter, randomized, open-label, blinded-endpoint trial aims to compare the clinical efficacy and safety of edoxaban-based treatment versus apixaban-based treatment in patients with cancer-associated venous thromboembolism (CAT). A total of 2,300 patients with active cancer and objectively confirmed venous thromboembolism will be randomized in a 1:1 ratio to receive edoxaban-based or apixaban-based treatment. The primary objective is to determine whether edoxaban-based treatment is non-inferior to apixaban-based treatment with respect to net adverse clinical events (NACE), defined as a composite of recurrent venous thromboembolism, venous thromboembolism-related death, or major bleeding according to the International Society on Thrombosis and Haemostasis criteria.

Sickle cell disease (SCD) is characterized by chronic hemolytic anemia, painful crises called vaso-occlusive crises (VOC) and chronic inflammation. Activated platelets from SCD patients contribute to both chronic inflammation and painful VOC. Individuals with the HbSC genotype experience anemia and less severe clinical manifestations than those with the HbSS genotype; however, they are at higher risk of venous thromboembolic events, particularly pulmonary embolism. This study aims to investigate whether sickle cell patients exhibit different thrombin generation profiles as well as distinct platelet activation and aggregation profiles, depending on their SS or SC genotype.

This study aims to determine the incidence of venous thromboembolic events (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), among hospitalized patients with interstitial lung disease (ILD). It will also identify potential risk factors associated with VTE and evaluate its impact on clinical outcomes. Patients with ILD admitted to the hospital will be assessed for clinical characteristics, disease severity, risk factors for thrombosis, and the occurrence of DVT or PE during hospitalization. The study findings may help improve early recognition of VTE and guide appropriate preventive and diagnostic strategies in hospitalized patients with ILD.

This trial seeks to evaluate a management strategy after the acute treatment duration (≥ 3 months of therapeutic anticoagulation) for patients with cancer and catheter-related upper extremity deep vein thrombosis (DVT).

The Computerized Registry of Patients with Venous Thromboembolism (RIETE) is a multidisciplinary Project initiated in march 2001 and consisting in obtaining an extensive data registry of consecutive patients with venous thromboembolism. The main objective is to provide information on the Internet to help physicians to improve their knowledge on the natural history of thromboembolic disease, particularly in those subgroups of patients who are usually not recruited in randomized clinical trials (pregnant women, elderly patients, disseminated cancer, severe renal insufficiency, patients with contraindications to anticoagulation therapy, extreme body weight, etc), with the purpose of decreasing mortality, frequency of thromboembolic recurrences as well as bleeding complications and arterial events. As an additional objective RIETE is also aimed to create predictive scores that help physicians to better identify patients with high risk of presenting some of these complications. The primary parameters recorded by the registry comprise details of each patient's clinical status, including any coexisting or underlying conditions, and the type, dose, duration and outcome (during the first 3 months of therapy) of antithrombotic treatment. Study endpoints are clinically recognized (and objectively confirmed) recurrences of VTE, major and minor bleeding complications, and death.

Patients with cancer are at high risk for life-threatening venous thromboembolism (VTE) yet rarely receive anticoagulant prophylaxis due to bleeding risks. Thus, effective prophylaxis in oncology requires a method to reduce VTE without increasing hemorrhage. The primary aim of the Statin Therapy to Prevent Cancer Associated Venous Thromboembolism (STAT-CAT) trial is to test whether rosuvastatin 20 mg daily for 12 months compared to placebo can safely prevent VTE in patients with newly diagnosed or recently relapsed cancer who are at increased thrombotic risk, are not planned to be anticoagulated, and who do not otherwise take statin therapy.

Smart technologies, such as wearable devices, mobile technologies, and artificial intelligence, are being investigated for use in health management. These technologies have the potential to be applied in disease pre-warning, decision-making support, health education, and healthcare maintenance. They are expected to address the challenges in managing thrombosis, improve access to high-quality medical resources in various regions, and enhance the development of a network for thrombosis rescue and treatment prevention. This study aims to evaluate the effects of a smart technology-assisted, patient-centered mobile health application for pulmonary thromboembolism management (mPEA) on the long-term outcomes of patients with pulmonary thromboembolism (PTE). The findings are expected to inform clinical practice and provide an evidence base for the long-term management of patients with PTE.

This study is a prospective, multicenter, randomized controlled trial of an interventional strategy using the ClotTriever System to achieve and maintain vessel patency (ClotTriever Intervention Arm) versus conservative medical management using anticoagulation therapy alone (Conservative Medical Management Arm) in the treatment of subjects with symptomatic unilateral iliofemoral DVT. The study will collect data on demographics, comorbidities, details from the DVT diagnosis and treatment, and clinical outcomes through the 6-month follow up visit.

After hip or knee replacement all patients receive a standardized treatment with blood thinners, this medication is called thrombosis prophylaxis. However, despite this standard treatment some individuals still develop venous thrombosis (VTE), while others experience bleeding. This indicates that not all patients have the same VTE risk following surgery. Individualizing the amount of thrombosis prophylaxis following surgery might lead to less thrombotic and bleeding events. In this study the investigators individualize the treatment with thrombosis prophylaxis based on the medical history of a patient. The main questions this study aims to answer are: Can thrombosis prophylaxis be shortened in patients with a low VTE risk to decrease the risk of bleeding without increasing the risk of VTE? Does an increase in the dose and duration of thrombosis prophylaxis in patients with a high VTE risk reduce the risk of VTE without inducing an unacceptable risk of bleeds? Researchers will compare both the shortened treatment in low VTE risk patients and the intensified and extended treatment in high VTE risk patients with the standard treatment to assess the risk of VTE and bleeding in comparison to the standard treatment. Participants will receive 4 questionnaires to evaluate whether they have experienced a VTE or bleed. For this study no additional hospital visits are necessary.

Background: The 2026 American Heart Association/American College of Cardiology (AHA/ACC) Pulmonary Embolism Guideline (Creager et al., Circulation 2026) introduced a novel five-category (A-E) clinical classification system with subcategories and an R modifier, replacing prior risk stratification frameworks. Prospective validation of this classification system using composite clinical outcomes is lacking. Objective: To evaluate the prognostic value of the 2026 AHA/ACC clinical categorization (Categories A-E plus R modifier) for predicting 30-day Major Adverse Pulmonary Embolism Events (MAPEE) in emergency department (ED) patients with acute pulmonary embolism (PE). Methods: Prospective observational cohort study conducted at Marmara University Faculty of Medicine Emergency Department, enrolling 600 consecutive adult patients with confirmed acute PE by computed tomography (CT) pulmonary angiography between April 2026 and January 2027. Primary outcome: MAPEE composite (all-cause mortality OR hemodynamic deterioration OR treatment escalation OR cardiopulmonary resuscitation) within 30 days. Secondary outcomes include area under the receiver operating characteristic curve (AUC) comparison with the European Society of Cardiology (ESC) 2019 risk stratification (exploratory), negative predictive value (NPV) of low-risk categories (A+B) for safe discharge, MAPEE trend across C1/C2/C3, and R modifier odds ratio. Statistical analysis: Jamovi v2.x. Reporting follows the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) 2007 checklist.

Direct oral anticoagulants (DOACs) have emerged as safe and efficacious ischemic stroke prophylaxis for non-valvular atrial fibrillation (NVAF). All four DOACs - apixaban, dabigatran, edoxaban, and rivaroxaban - were shown to reduce the risk of major bleeding compared to warfarin. The predictable pharmacokinetic profiles of DOACs also favour their use over warfarin. Together with increasing AF incidence due to population ageing, increased AF detection, and territory-wide reimbursement schemes, DOAC prescriptions have been surging worldwide. In Hong Kong, more than 78,354 patients received DOAC from January 2009 through April 2021 according to the Hospital Authority registry. The more liberal use of DOACs has led to new issues that require a thorough understanding of ethnic-specific DOAC pharmacokinetic profiles. For instance, 12- 15% of anticoagulated patients annually required interventional procedures that involve temporary discontinuation of DOAC for 48 hours or more. Although guideline-based periprocedural DOAC interruption resulted in a low 30-day thromboembolism rate of 0.16% - 0.6% in a Caucasian cohort, same measures for elective colonoscopies in a local population-based study resulted in a 30-day periprocedural thromboembolism rate of up to 2.2%. Although these studies cannot be compared directly, the remarkable interethnic discrepancy between the two cohorts warrants further pharmacokinetic and pharmacogenomic studies. More importantly, quantifying residual DOAC levels during the interruption periods may imply on duration of periprocedural DOAC interruption, length of hospital-stay, and the risk of thromboembolic and bleeding complications. Mapping inter- and intra-individual variations in DOAC levels may also impact on the management of ischemic stroke among DOAC recipients. Epidemiological studies have shown alarmingly up to 13% of acute ischemic stroke patients were on anticoagulation prior to stroke onset with increasing number of DOAC. These patients received low rates of recanalization therapy due to apprehension of bleeding complications, thus compromised survival and neurological recovery. A prospective study that reveals Asian-specific DOAC pharmacokinetic profiles may inform cross-disciplinary, territory-wide periprocedural care and acute stroke intervention strategy for the rapidly expanding DOAC population.

The goal of the PARTUM trial is to determine if taking low-dose aspirin daily for 6 weeks after delivery is similar (non-inferior) to usual care low-molecular-weight heparin injections to prevent venous thromboembolism (VTE: blood clots in the legs or lungs) for postpartum individuals with VTE risk factors.

This trial seeks to assess the feasibility of a full-scale, double-blind, placebo-controlled, randomized trial assessing whether low-dose colchicine (0.5 mg daily) reduces the risk of post-thrombotic syndrome (PTS) in patients with proximal lower extremity deep vein thrombosis (DVT).

The investigators are studying whether treatment with a proton pump inhibitor called omeprazole reduces gastrointestinal bleeding in older adults taking blood thinners for a blood clot (venous thromboembolism). The purpose of this study, a pilot study or a feasibility study, is to test the study plan and determine whether enough participants will join a larger study and accept the study procedures.

This study focuses on two serious and common medical conditions: heart failure and pulmonary embolism (a blood clot in the lungs). Heart failure happens when the heart cannot pump blood effectively, and it is one of the main reasons older adults are admitted to the hospital. Pulmonary embolism can be life-threatening and may worsen heart failure or even trigger it. Doctors believe that pulmonary embolism may often go undetected in patients who come to the hospital with symptoms of acute heart failure, such as sudden shortness of breath. This is because both conditions can cause similar symptoms, making it difficult to tell them apart. As a result, doctors may sometimes assume the symptoms are only due to heart failure and not investigate further for a possible blood clot. However, missing a pulmonary embolism can have serious consequences. Studies suggest that some patients with heart failure who die may actually have had an undiagnosed pulmonary embolism. Current medical guidelines recommend checking for pulmonary embolism when the cause of breathing problems is unclear, but in real-life practice, this is not always done. The goal of this study is to find out whether pulmonary embolism is underdiagnosed in patients with suspected acute heart failure and whether systematically testing for it could improve patient outcomes. To do this, the study will compare two approaches in several hospitals. In half of the hospitals, doctors will follow their usual practice and decide case by case whether to test for pulmonary embolism. In the other half, doctors will systematically test all eligible patients for pulmonary embolism using recommended diagnostic methods. Adult patients admitted with recent or worsening breathing difficulties and signs of acute heart failure may be included in the study, provided they give their consent. Researchers will collect information about their symptoms, tests, diagnosis, and treatments. Patients will be monitored during their hospital stay and for three months afterward. The study will track important outcomes such as survival, new blood clots, bleeding events, repeated hospital visits for breathing problems, and overall time spent in the hospital. The researchers expect to include about 740 patients in total. They estimate that pulmonary embolism may be found in about 1% of patients with usual care, but up to 5% when doctors systematically look for it. This study aims to better understand how often pulmonary embolism occurs in patients with acute heart failure and whether more systematic testing could lead to earlier diagnosis and better care. The results could help improve medical practice and reduce complications or deaths related to missed diagnoses.

Lower limb trauma requiring immobilization is a very frequent condition that is associated with an increased risk of developing venous thromboembolism (VTE). The TRiP(cast) score has been developed to provide individual VTE risk stratification and help in thromboprophylactic anticoagulation decision. The recent CASTING study had confirmed that patients with a TRiP(cast) score \<7 have a very low risk of VTE and could be safely manage without prophylactic treatment. Conversely, patients with a score ≥ 7 have a high-risk of VTE and require a prophylactic anticoagulant treatment. Low molecular weight heparins (LMWH) have been shown to be effective in this indication. However, in the CASTING study, the 3-month symptomatic VTE rate was 2.6% in this subgroup despite LMWH prophylactic treatment. This result suggests that LMWH are not sufficiently effective in this particular subgroup of high-risk patients. Direct oral anticoagulants, and in particular rivaroxaban, may be an effective and safe alternative to LMWH. In the PRONOMOS study, comparing LMWH with rivaroxaban in patients who had undergone non-major lower limb surgery, the relative risk of symptomatic VTE was 0.25 (95% CI = 0.09 - 0.75) in favor of rivaroxaban 10mg. No significant increase in bleeding was found. In addition, as LMWH treatment requires subcutaneous daily injections, the use of rivaroxaban may positively impact patients' quality of life as well as being effective in medico-economic terms. The aims of this study are to demonstrate that rivaroxaban is at least as effective, easier to use and more efficient than LMWH in patients with trauma to the lower limb requiring immobilisation and deemed to be at risk of venous thromboembolism (TRiP(cast) score ≥ 7). High-risk patients are randomized to receive either rivaroxaban or LMWH. They are followed up at 45 days and 90 days to assess the occurrence of thrombotic events or bleeding, as well as their satisfaction with the treatment received.

Two groups of patients will be compared: One group of patients with a history of venous thromboembolic disease and one group without. Both groups will be subjected to a walking test and with electrocardiogram measurements and blood tests.

Major risk after pulmonary embolism (PE) is recurrence, fatal in 10% of patients. Patients with PE can be stratified in 3 groups according to the risk of recurrence : very low risk, high risk or Intermediate risk. Little is known about this last group. Anticoagulation is efficient to prevent recurrence but is currently not recommended for patient with an intermediate risk of recurrence. Identifying risk factors of recurrent PE remains a major issue to identify sub-groups of patients who would require lifelong anticoagulation. In 30-40% of cases, PE patients develop residual pulmonary vascular obstruction (RPVO), which has been found to be associated with an increased recurrence risk. This last observation was mostly reported in patients with unprovoked PE (patients with high risk of recurrence) and RPVO was measured using conventional planar lung scan. In patients with an intermediate risk of recurrence, the impact of RPVO has been much less studied. In addition, the definition of RPVO was variable according to studies and correlation between RPVO burden and recurrence risk has not been clearly demonstrated. This might be explained by the inherent limitation of RPVO quantification using conventional planar imaging, which is only based on a visual estimation on 2-dimensional images. Ventilation/Perfusion Single Photon Emission Computed Tomography (V/Q SPECT/CT) is a new method of scintigraphic image acquisition that offers the advantage of 3-dimensional imaging, enabling more accurate and reproducible quantification of RPVO. The main hypothesis of this study is that in patients with PE at intermediate risk of recurrence, RPVO computed with V/Q SPECT/CT imaging may be an important predictor of recurrence.

Endovenous interventions are keyhole operations for varicose veins that are carried out from within the vein itself. Varicose veins are enlarged veins close to the surface of the skin. They are connected to the bigger deeper veins in the leg (known as deep veins). Because of this, operations to close the varicose veins can increase the chance of a blood clot forming in the deep veins. Blood clots in the deep veins happen in around 1 in 50 people after endovenous operations. A clot in the leg can cause swelling, pain, and other long-term problems. If a clot in the leg breaks off and travels to the lungs, it can cause problems with the lung' ability to move oxygen from the air into the blood and may, in rare cases, be life threatening. Varicose vein procedures may carry a slightly higher risk of blood clot formation, and we are currently unsure if current clot reducing medicines are beneficial in preventing blood clots in people having varicose vein procedures. This study will investigate if it is worthwhile prescribing medicines to reduce blood clots after varicose vein procedures.

The clinical significance of pulmonary embolism (PE) limited to the subsegmental pulmonary arteries, so called isolated subsegmental pulmonary embolism (SSPE), remains controversial. Whether isolated SSPE represents "true" PE, a clinically more benign form of PE, a physiologic lung clearing process, or a false positive result (artifact) is currently unclear and hence, whether patients with isolated SSPE benefit from anticoagulant treatment is uncertain. Despite growing evidence from observational studies that withholding anticoagulation may be a safe option in selected patients with isolated SSPE (i.e., those without concomitant deep vein thrombosis, cancer, etc.), most patients with isolated SSPE receive anticoagulant treatment, which is associated with an increased risk of bleeding. The overall objective of the randomized controlled SAFE-SSPE trial is to evaluate the efficacy and safety of clinical surveillance without anticoagulation compared to anticoagulation treatment in low-risk patients with isolated SSPE.

This study aims to compare the effectiveness and safety of three treatment strategies (Anticoagulation, Thrombolysis, and Mechanical Thrombectomy) for patients with intermediate-high risk acute pulmonary embolism (PE) in a real-world setting. Approximately 1,300 patients will be enrolled across multiple centers in China. Patients will be followed for 90 days to assess mortality, heart function recovery, bleeding risks, and quality of life. The results will help guide personalized treatment decisions and healthcare policy.

Cancer patients are at higher risk of getting a blood clot (known as venous thromboembolism (VTE)) especially during chemotherapy and some patients are more at risk than others. These clots can be prevented by using blood thinners (known as anticoagulants) but these are not suitable for everyone as they also carry a risk of bleeding. This study aims to identify which chemotherapy patients are most at risk of a blood clot and at what point in their treatment this is likely to happen. In this project biomarkers in the blood that are involved in blood clotting will be measured in cancer patients at four stages during chemotherapy to see how the biomarkers change during treatment. The blood samples for these tests are taken at the same time as the normal routine blood tests done before a chemotherapy cycle. Biomarker levels will be compared between those patients who subsequently get a VTE and those who do not get a VTE. This will help develop a biomarker based blood test to predict clots during chemotherapy. The biomarker based test will also be compared with other methods of predicting VTE in cancer patients which are currently in use. In the future, this blood test might be used to see if patients are at high risk of a clot during chemotherapy and provide a method to optimise the use of preventative anticoagulants in cancer patients during chemotherapy.