Active clinical trials for "Venous Thromboembolism"

Venous thromboembolism (VTE) and atherosclerotic cardiovascular disease share common risk factors and frequently coexist in the same patients. Their management requires use of antithrombotic agents: anticoagulant therapy (AC) for secondary prevention of VTE recurrence, antiplatelet (AP) for secondary prevention of major adverse ischemic cardiovascular and cerebrovascular event (MACCE) in patients with atherosclerotic cardiovascular disease (coronary artery disease, atherosclerotic cerebrovascular disease, lower extremity peripheral arterial disease). Side effects of antithrombotic drugs are the 1st cause of emergency admission and hospitalization for an adverse drug reaction (mainly bleeding), and the combination of AC with AP strongly increases this risk. Up to one third of VTE patients receive concomitant AP therapy, with conflicting results on patient outcomes. Concomitant therapy (AC+AP) has been associated with a higher risk of bleeding (up to 3-fold) when aspirin was associated with vitamin-K antagonist (VKA) in a multicenter cohort study, or with direct oral anticoagulants (DOACs) for acute VTE in a post-hoc subgroup analysis. Conversely, patients with acute VTE in whom clinicians decided to maintain AC+AP were found to have an increased risk of MACCE without any higher risk of bleeding, in a multicenter registry. However, in most cases, the type (aspirin or another) and indication (primary versus secondary prevention) of AP was unknown, as was the duration of the combination AC+AP, and therefore these observational results may be confounded. Therefore, there is persistent equipoise regarding the benefit/risk of combining an antiplatelet therapy with anticoagulation in patients undergoing treatment for VTE, when there is a prior history of atherosclerotic cardiovascular disease. This may explain why clinical practice varies widely. Considering the conflicting data about the risk of bleeding in patients on AP therapy for secondary prevention, who need to start full-dose anticoagulant therapy for acute VTE, a randomized trial comparing the two strategies, in patients with acute VTE and with history of stable atherosclerotic cardiovascular disease is needed and justified. We hypothesize that a strategy based on the prescription of a full-dose AC therapy alone will decrease the risk of bleeding, when compared to the the strategy of combined AP and full-dose AC therapies, and that this strategy will translate in a positive net clinical benefit (a composite of clinically relevant bleeding, recurrent venous thromboembolism, and major adverse ischemic cardiovascular and cerebrovascular events).

Aim of the study is to investigate whether the influence of drugs inducing of CYP 3A4 isoenzyme of CYP450 and P-gp transporter significantly affect plasma levels of DOACs in patients with NVAF and venous thromboembolism

The aim of this study is to investigate the efficacy and safety of rivaroxaban in obese patients undergoing bariatric surgery. The objectives are to assess the safety and feasibility of venous thromboembolism (VTE) prophylaxis and lung embolism with Rivaroxaban 10mg as an oral anticoagulant. After bariatric surgery patients receive the study medication Xarelto 10mg QD for 7, resp. 28 days. All clinically thromboembolic events will be assessed by ultrasound or CT, respectively, as soon as apparent. In addition, patients are screened for VTE at day 28 by ultrasound to detect clinically inapparent thromboses. In a subgroup of study patients (patients from the University Hospital Inselspital, Bern) PK/PD parameters are assessed following the last intake of rivaroxaban at day 28.

The study is aimed at assessing the role of the activity of high-risk markers of thrombotic events (MCP-1, MIP1α, IP-10, phosphatedylserine, calreticulin) on the development of thrombotic complications in patients with COVID -19.

Myeloproliferative neoplasms (MPNs) are blood disorders that occur when the body makes too many white or red blood cells, or platelets. This overproduction of blood cells in the bone marrow can create problems for blood flow and lead to various symptoms. One of the major problems is the formation of blood clots. These may form in the veins of a patient's legs or arms where they cause leg or arm pain, swelling or difficulty walking. These clots may travel to the lung and then cause chest pain, shortness of breath and sometimes death. Blood clots can also lead to poor or no blood flow to one's heart, brain, or other organs, causing damages that cannot be easily or ever repaired, such as stroke or heart attack. Patients diagnosed with certain types of MPN are associated with a higher risk of developing blood clots and related complications. For this reason, MPN patients are usually treated with low-dose aspirin, a common drug used for blood clot prevention, on long-term basis to prevent the formation of blood clots and other complications. However, recent studies also show that the risk of blood clots remains elevated in MPN patients treated with aspirin, and there may not be improvement or reduction in fatal or other events that are associated with blood clots. In addition, since this medical condition is rare, so there's a lack of studies done with high quality results to help physicians decide the best treatment plan for these patients. The study drug, apixaban, is a new type of orally-taken blood thinner that has been shown to be effective and safe for prevention and treatment of blood clots in various patient populations. The investigators will evaluate whether apixaban is safer and/or better at preventing blood clots and other complications in MPN patients compared to aspirin.

Safe and effective severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines may reduce the transmission of and achieve population immunity against the COVID-19 pandemic, which accounted for more than 3.75million deaths worldwide. With World Health Organization's (WHO) effort on ensuring equitable access to COVID-19 vaccines, vaccination rate may increase in the near future. On the other hand, vaccination hesitancy has emerged as a major hindrance on the global vaccination campaigns in certain areas due to safety concerns, social factors, and public health policies. For instance, a recent survey conducted in Hong Kong showed a low vaccine acceptance rate of 37%. Long-term safety concerns and post-vaccination events relayed by the social media maybe reasons for vaccination hesitancy. Among which, cerebrovascular accidents (CVA) after vaccination were one of the most frequently reported post-vaccination events. These reports ranged from ischemic strokes in elderly patients with multiple cardiovascular co-morbidities, to hemorrhage strokes in otherwise "young-and-fit" adults. While many of these events were investigated by the COVID-19 immunization expert committee, an important premise to address the apprehension of CVA after vaccination is the provision of evidence-based information of the impact of COVID-19 vaccines on brain health. In this prospective, longitudinal, observational study, we aim to elucidate the relationship between COVID-19 vaccines and cerebrovascular health in healthy citizens in a population-based cohort.

The study will evaluate the effectiveness of a novel, real-time risk prediction model for identifying pediatric patients at risk for developing in-hospital blood clots (or venous thromboembolism [VTE]) based on data easily extracted from the electronic medical record. The study will assess whether using the risk percentages for developing VTE derived from the model increases the number of high-risk patients screened by the pediatric hematology team, which may may lead to an overall reduction in the number of pediatric VTEs seen at Monroe Carell Jr. Children's Hospital at Vanderbilt.

The purpose of this study is to investigate clinical, biochemical and genetic risk factors for venous thromboembolism in pregnancy and pregnancy related vascular complications, and the long-term outcome of such complications including implications for quality of life.

Background: Venous thromboembolism (VTE) includes the abnormal clotting of blood in a deep vein of the upper or lower limbs (deep vein thrombosis) that may travel to and block a blood vessel in the lung (pulmonary embolism). Some people with sickle cell disease (SCD)-a red blood cell disorder-seem to be at greater risk for developing these blood clots. Researchers want to study the blood of people with SCD and VTE as well as healthy people to develop better treatments to prevent blood clots. Objective: To study blood clotting in SCD because it is the most common cause of vascular death after a heart attack or stroke. Eligibility: People ages 18-80 who have SCD (with or without a history of blood clots) or the trait for SCD, and healthy volunteers Design: Participants will be screened with medical history, physical exam, and medical records review. They will give blood samples. Participants will have phone calls either every 3 months or once a year, for 2 years. They will give updates on their health. They may give additional medical records. The phone calls may last up to 30 minutes. If participants have a VTE or pain crisis episode, they may visit the Clinical Center. These visits may last up to 4 hours. They will repeat the screening tests and give blood samples. Some participants may be invited to take part in blood studies. After 2 years, some participants will have a follow-up visit at the Clinical Center. Participation will last for about 2 years.

This is a phase 4 cohort prospective, open, national, multicentre study that collects data on history of patients treated chronically with anticoagulant drugs, including the novel direct oral anticoagulants (DOACs). The Registry is designed solely for observational purposes and is not intended to have any influence on the treatment of the single patients included. Patients are included when they start the anticoagulant treatment, whatever the drug used, or when they shift from a vitamin K antagonist (VKA) drug to one of the novel direct oral anticoagulants, provided that the therapy is expected to last at least 3 months. The general aims of the study are to provide a better evaluation of efficacy and safety of different treatment options, and to improve our understanding of the risks/benefits of the various anticoagulant drugs and the different therapy options. The Registry is open to the participation of clinical centres or individual professionals (now called Participants) that are involved with management of anticoagulated patients.