Active clinical trials for "Venous Thrombosis"

This study aims to investigate a novel positron emission tomography(PET)-probe for imaging of fresh intravascular blood clots in pulmonary embolism (PE) and deep venous thrombosis (DVT).

The goal of this study is to develop strategies that will improve outcomes for patients with deep vein thrombosis (DVT), using in vivo FDG-PET inflammation imaging to better predict the development of the post-thrombotic syndrome (PTS). New approaches are needed to improve the outcomes of patients with DVT, a disease that affects up to 600,000 patients per year in the US alone. DVT acutely places patients at risk of death from pulmonary embolism and causes 50,000 deaths annually in the US. Moreover, up to 30-50% of patients will develop PTS, an illness characterized by inflammation-driven fibrotic vein wall injury, and persistent thrombus obstruction. PTS occurs despite anticoagulant therapy, and produces chronic disability from leg pain, heaviness, edema, skin pigmentation, and ulcers; some patients may even require amputation. PTS impairs quality of life to the same extent as chronic obstructive pulmonary disease or diabetes. Therefore new diagnostic insights into PTS are urgently needed. There are several major challenges to improve outcomes in PTS: A) Limited in vivo knowledge regarding inflammation and the development of PTS; B) L Lack of predictive approaches to identify patients at high risk for PTS that will preferentially benefit from novel therapies. Recently, our laboratories have harnessed FDG-PET molecular imaging to illuminate DVT inflammation in vivo, and to provide a new strategy to diagnose recurrent DVT, a vexing clinical problem (Hara et al. Circulation 2014). We now propose to further develop FDG-PET to improve outcomes in DVT and PTS. The objective of this application is to develop FDG-PET as an inflammation imaging approach to assess DVT inflammation and predict risk of developing PTS in human subjects; Hypothesis 1A: Inflammatory activity in DVT (quantified acutely, using FDG-PET imaging within 0-7 days after DVT) will predict PTS incidence (primary) and severity (secondary) within a 24 month follow-up period. Hypothesis 1B: Inflammatory activity in DVTs (quantified sub-acutely, using FDG-PET imaging within 21-28 days after DVT), will predict PTS incidence and severity. Eighty patients with DVT will be imaged using FDG-PET/CT acutely (0-7 days of DVT diagnosis), and sub-acutely (21-28 days after diagnosis). Subjects will be evaluated repeatedly for up to 2 years to detect clinical evidence of PTS (Villalta score), ultrasound findings for structural venous injury, and soluble biomarkers of systemic inflammation. Subsequently, we will evaluate the relationship between FDG DVT activity and the development of PTS.

Thrombo-embolic venous diseases are represented by deep venous thrombosis and/or pulmonary embolism. In some patients with repeated thrombosis or occurrence of thrombosis in unusual sites, the etiological workup remains negative, which represents a problem for the management of the anticoagulant treatments. Recently, two factors have been identified as important in the physiopathology of hemostasis and coagulation: the presence of clonal hematopoiesis of indetermined potential (CHIP) and the formation of neutrophil extracellular traps (NETs). In this study, these two factors will be studied in patients with repeated venous thrombosis or thrombosis occurring in unusual site.

In this cohort study, the investigators will investigate the concentration of biomarkers, e.g., inflammatory, anti-inflammatory, immunological, senescent, biochemical ratio-calculations and blood cell type among first time lower extremity deep venous thrombosis patients with and without SARS-CoV-2 infection and long term complications with a 2-year follow-up.

The objective of this study is to evaluate the diagnostic efficiency of general practitioners for the diagnosis of proximal deep vein thrombosis of the lower limbs compared with whole-leg ultrasound with Doppler performed by the vascular physician.

Open and multicenter randomized clinical trial (1:1) comparing limited screening with extended screening with the performance of Positron emission tomography-computed tomography (PET-CT) scan in the search for neoplasms in patients with unprovoked venous thromboembolic disease at high risk of developing cancer at follow-up. Introduction: Cancer screening in patients with unprovoked venous thromboembolic disease (VTE) is controversial. In the last years, a score has been developed that selects patients at high risk of developing cancer during follow-up. Objective: To estimate the impact of an active cancer search strategy using 18-fluordesoxiglucose (FDG) PET-CT in unprovoked VTE with high-risk to develop cancer. Specific Objectives: 1) Number of neoplasms diagnosed in the screening process: 2) number of neoplasms diagnosed at an early stage, 3) impact on survival of the strategy; and 4) impact on the quality of life. Cancer will be considered from 30 days up to 12 months after the diagnosis of VTE. Scope: 20 Spanish hospitals. Design: Open-label, multicentre Randomized clinical trial (1: 1) comparing the performance of PET-CT versus limited screening for cancer. Population: Patients older than 18 years with unprovoked VTE at high risk of presenting cancer at follow-up (≥3 points in the score of Jara-Palomares et al., Chest 2017). Follow-up: 12 months after VTE. Sample: The sample size calculated is 650 patients, to obtain a power of 80%, with a level of significance of 5%, and taking into account a 10% loss of follow-up.

Thromboprophylaxis for liver surgery can be commenced either preoperatively or postoperatively. Despite a clear trade-off between thrombosis and bleeding in liver surgery patients, there is no international consensus when thrombosis prophylaxis should be commenced in patients undergoing liver surgery. As far as we know, there are no prospective randomized trials in this field, and current guidelines are unfortunately based on very low quality evidence, that is, a few retrospective studies and expert opinion. Both American and European thromboprophylaxis guidelines for abdominal cancer surgery support the preoperative initiation of thromboprophylaxis, but these guidelines do not specifically address the increased bleeding risk associated with liver surgery. On the contrary, Dutch guidelines recommend postoperative thromboprophylaxis only, because of lack of evidence for preoperative thromboprophylaxis. Traditionally, many liver surgery units have been reluctant in using preoperative thromboprophylaxis due to the potentially increased risk of bleeding complications. Enhanced Recovery After Surgery (ERAS) Society Guidelines recommend preoperative thromboprophylaxis in liver surgery, but the guidelines provide no supporting evidence for this recommendation. Overall, the amount of evidence is scarce and somewhat contradictory in this clinically relevant field of thromboprophylaxis in liver surgery. The aim of this study is to compare pre- and postoperatively initiated thromboprophylaxis regimens in liver surgery in a randomized controlled trial.

Compression ultrasound is commonly used in emergency department. Accuracy to rule out deep vein thrombosis is excellent but lower then Ddimer assessment which is actually gold standard. With progress in formation of emergency physicians (EP), quality of material used, the investigators hypothesize that compression ultrasound can rule out deep vein thrombosis in case of non high probability, as standard care and DDimer assay.

The risk of developing a blood clot occurs in up to 60% of all critical care patients. Many times enoxaparin (or Lovenox) is given to patients who are at a higher risk of developing clots in their legs or lungs. There are two standard doses of enoxaparin that are recommended by the drug companies. These two doses have never been directly compared in trauma, general, and vascular surgery patients. The purposes of this study are: to compare the development of blood clots in patients receiving 30mg twice daily of enoxaparin compared to patients receiving 40mg once daily of enoxaparin. to determine if there is higher risk of bleeding complications in patients receiving 30mg twice daily of enoxaparin compared to patients receiving 40mg once daily. Patients enrolled into the study will be randomized to receive enoxaparin, 30mg twice daily or enoxaparin, 40mg once daily. Patients will then be monitored for signs and symptoms of blood clots. At the time of discharge (or before, if medically indicated), an ultrasound test will be performed to look for blood clots in the patient's legs. The investigators will compare incidence of blood clots formed between the 2 groups of patients to determine if one dose of enoxaparin relates to a lower rate of blood clots in critically ill patients. The investigators will also compare the incidence of bleeding complications between the 2 groups.

This study aims to compare two different external calf compression devices applied in healthy individuals. These devices are commonly used in medical care in order to prevent the formation of blood clots, for example during immobilization after surgery. We aim to confirm the effects of external cyclic compression on healing and blood clotting and also to identify the one which is more effective.