View clinical trials related to Thrombosis.
Filter by:Whether isolated distal DVT (IDDVT), DVT confined to the calf, should be looked for and diagnosed to allow them to be treated with anticoagulants remains one of the still unsolved issues in vascular medicine, especially because of the insufficient data on clinical risks of untreated distal DVT. Management studies have shown that it is safe to withhold anticoagulation in outpatients with suspected DVT if compression ultrasonography (CUS) limited to the proximal deep veins yields normal results on presentation and on repeated examination after 5 to 7 days. This strategy is based on the premise that IDDVT do not need to be diagnosed and treated, what is necessary when they extend involving the proximal veins. There is no general agreement, however, on the assumption that the non-extending IDDVT do not need to be diagnosed and treated, and many authors recommend to perform a single CUS examination extended to the distal deep veins. All the available studies have treated with anticoagulants the diagnosed IDDVT and no adequate information is available on the risk of IDDVT left untreated. The present study, performed in outpatients with suspected leg DVT, aims at assessing the clinical consequences of IDDVT diagnosed (by a complete US investigation) but not treated because the results of this investigation remain blind to both the patient and the treating doctor, whereas the diagnostic-therapeutic procedure remains the usual one, based on CUS investigation limited to diagnose proximal DVT, to be repeated after 5-7 days (or earlier) to exclude an extension to proximal veins of an IDDVT potentially present.
Thrombosis is a significant medical complication in children with chronic diseases. The currently utilized treatments have many drawbacks which can lead to poor outcomes. More modern therapies are available but have not been systematically tested in children. This study will determine whether one such medication, bivalirudin is a safer and more effective alterative. This study will monitor what effects the drug has upon the child's body and how the body processes the study drug (absorption, metabolism and elimination). The study will also evaluate the drug's effectiveness by following how long it takes to dissolve the clot. The safety issues being monitored relate to any observations of major or minor bleeding episodes after taking the drug, and/or any other side effects.
Low-molecular-weight heparin (LWMH) appears to be at least as effective and safe as standard, unfractionated heparin (UFH)for the treatment of patients with deep vein thrombosis(DVT) and may also be so in patients with pulmonary thromboembolism (PTE). Only limited data are available on the evaluation of body weight adjusted LWMH and standard UFH for the initial treatment of PTE in Chinese population. The aim of this study is to determine whether body weight-adjusted, subcutaneous Nadroparin is as effective and safe as UFH for treatment of patients with objectively documented PTE.
The purpose of this study is to determine if the use of adjunctive Pharmacomechanical Catheter Directed Thrombolysis, which includes the intrathrombus administration of rt-PA--Activase (Alteplase),can prevent the post-thrombotic syndrome(PTS)in patients with symptomatic proximal deep vein thrombosis(DVT)as compared with optimal standard DVT therapy alone.
This is a multicenter, cohort study evaluating an adapted rivaroxaban dose regimen in patients with acute, proximal deep-vein thrombosis (DVT) or acute pulmonary embolism (PE) who concomitantly use a strong cytochrome P450 isoenzyme 3A4 (CYP 3A4) inducer for the entire 3-month study duration.
Heparin is frequently used in central venous catheters (CVCs) in post-operative cardiac patients. It remains unclear if a heparin infusion, compared to a normal saline infusion, prevents thrombosis of CVCs after surgery. This study will answer the question: does a low-dose heparin infusion (10 units/kg/h) prevent thrombosis, compared to a normal saline infusion, in patients less than one year of age after cardiac surgery?
This registry collects observational data about how mid-length AngioJet catheters (ie XPEEDIOR and DVX models) are used in routine clinical practice.
Venous thromboembolism (VTE) remains a major cause of maternal morbidity and mortality in developed countries. Objective diagnosis of pulmonary embolism (PE) and/or deep vein thrombosis (DVT) in pregnancy is crucial. Failure to identify PE or/or DVT will place the mother's life at risk, and unnecessary treatment will not only expose her to anticoagulants but will also label her as having had VTE. Thus, this diagnosis has serious implications for the management of her present pregnancy, and for other aspects of her life ranging from contraception to thromboprophylaxis in future pregnancies and hormone replacement therapy in later life. It is therefore critical that all women with symptoms or signs that suggest venous thromboembolism have appropriate investigation and diagnosis based on objective diagnostic tests. The current diagnostic approach in suspected PE is based on sequential diagnostic tests: 1) assessment of clinical probability, 2) fibrin D-dimer measurement, 3) compression ultrasonography of lower limb veins and 4) multi-slice computed tomography (MSCT). However, physicians are reluctant to perform MSCT in pregnant women because of potential adverse effect of radiation exposure to the fetus. For this reason, ventilation/perfusion or perfusion-only lung scan has been the cornerstone of PE diagnosis in pregnant women. Indeed, perfusion lung scan was assumed to be associated with less radiation than computed tomography (CT). However, this technique is now widely abandoned in the usual diagnostic strategy of PE for the following reasons: it is not widely available; its interpretation may be difficult and the test may be inconclusive in the presence of other chest abnormalities. Moreover, recent data convincingly show that the radiation exposure associated with single-slice or multi-slice CT exposes the fetus to less radiation than perfusion lung scan. However, the use of CT has never been adequately validated in pregnant women with clinically suspected PE. The investigators, therefore, plan to set up a prospective management study in which pregnant women with suspected PE will undergo a sequential diagnostic strategy based on 1) assessment of clinical probability 2) D-dimer measurement 3) compression ultrasonography, and 4) MSCT. Nowadays, the overestimated fear of radiation exposure for the fetus leads to an irrational attitude and inadequate investigations in pregnant women with suspected PE, even though both European [3, 4] and North-American guidelines [5] suggest that only objective testing may accurately rule out the disease. The proposed study should lead to an increased awareness of the risks and benefits of appropriate imaging in pregnant women suspected of PE and should result in a more rational management of this under-studied patient group.
STUDY QUESTIONS - What is the real prevalence of platelet "resistance" to aspirin during the acute phase of stroke and after 3 months, and 1 year, as measured using different platelet function tests? - Do all methods measure similar levels of resistance, or are some methods more sensitive than others? - Does this resistance result in a worse clinical prognosis? Is this result independent of other variables? OBJECTIVES 1. Hospital Phase (Acute Stroke) - Determination, using various methods, of the prevalence of platelet hyperreactivity in patients treated with aspirin to treat ischemic stroke (acute phase) - Comparison of different assessment methods and identification of the most accurate of these - Identification of variables that correlate with platelet hyperreactivity 2. Follow-up Phase - Correlation between platelet hyperreactivity and important clinical outcomes at 12, 24, and 36 months - Correlation between platelet hyperreactivity and death or dependency at hospital discharge, at 3, 12, 24, and 36 months (Modified Rankin Scale) - Correlation between platelet hyperreactivity and recurrent stroke of any type - Correlation between different methods for evaluating platelet functions and identification of the most accurate method - Analysis of hyperreactivity over time THE STUDY - The study will include 200 consecutive patients seen in the emergency department of a large, urban hospital (1500 inpatient beds) and diagnosed with stroke in the acute phase; these patients will be treated with aspirin for an undetermined period - The investigators will not include patients who require full anticoagulation treatment, regardless of the cause - Importantly, the analysis of primary and secondary outcomes will be carried out after blinding the examiner to the results of the platelet aggregation tests PLATELET TESTS - Whole Blood Aggregometer, ChronoLog - VerifyNow, Accumetrics - PFA-100, Siemens - Plateletworks, Helena - Impact-R, Diamed - Serum thromboxane B2
The purpose of this study is to determine the effect of clopidogrel or aspirin reactivity as measured by a point-of-care platelet function assay on thrombotic or bleeding events after percutaneous coronary intervention (PCI) with drug eluting or bare metal stent. Methods: Platelet reactivity on clopidogrel and aspirin therapy is measured before PCI with VerifyNow (Accumetrics Inc.,San Diego, CA, USA) P2Y12 or aspirin assay respectively in 1000 consecutive patients from 20 centers in France undergoing coronary angioplasty with stent. Exclusion criteria are: Acute myocardial infarction, treatment with vitamin K antagonists and the use of antiGP2b3a before PCI. All patients are pre-treated with clopidogrel and aspirin. Non-response to aspirin or clopidogrel is determined according to the result of the VerifyNow assay (cut off : < 15 % for P2Y12 and > 550 ARU for aspirin). The primary end point is the occurrence of definite or probable stent thrombosis (ARC definition) and the secondary end-points include global and cardio-vascular mortality, non fatal myocardial infarction and major bleeding. A clinical evaluation is scheduled at discharge and by telephone contact at one month and one year.