D-Dimer Determined Anticoagulation INTENSITY in Patients With Mechanical Valve Replacement

Study Overview
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Brief Summary
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The optimal intensity of oral anticoagulation in China patients undergoing mechanical valve replacements is still controversial due to the different risk profiles of thrombophilia and bleeding in Chinese patients. Elevated D-dimer could reflect a pro-thrombogenic or prothrombotic state, and thus might be used to decide the intensity of oral anticoagulation. This study was to evaluate whether elevated D-dimer levels could help to determine the intensity of oral anticoagulation in patients with mechanical heart valve prostheses.

Detailed Description
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Background: The optimal intensity of oral anticoagulation in China patients undergoing mechanical valve replacements is still controversial due to the different risk profiles of thrombophilia and bleeding in Chinese patients. Elevated D-dimer could reflect a pro-thrombogenic or prothrombotic state, and thus might be used to decide the intensity of oral anticoagulation. Objective: This study was to evaluate whether elevated D-dimer levels could help to determine the intensity of oral anticoagulation in patients with mechanical heart valve prostheses. Methods: A single-center, prospective study was performed. 748 Patients with mechanical valve replacement who had received oral anticoagulation. The patients were randomly assigned to three groups The intensity of anticoagulation for group one was standard intensity (INR:2.5-3.5). The intensity of anticoagulation for group two was kept at low intensity without adjustment (INR:1.8-2.6), and for group three , The intensity of anticoagulation maintained at low level initiatively (INR:1.8-2.6), D-dimer testing were analyzed two times at 3 month later. In case of D-dimer level elevated, adjusted the intensity of anticoagulation to standard level. The endpoint of the study was the subsequent thromboembolic and major bleeding during an average follow-up of 2 years.

Official Title
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D-dimer Levels Determined the Intensity of Anticoagulation Therapy to Improve Outcomes in Patients With Mechanical Valve Replacement

Conditions
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Heart Valve Disease

Intervention / Treatment
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* Drug: Warfarin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age>18years,male or female without pregnancy; Suffered the mechanical valves replacement in Wuhan Asia Heart Hospital; The operation type was Mitral valve replacement or Double valves replacement(aortic and mitral valve replacement). Exclusion Criteria: Patients with following diseases within 3 months. deep venous thromboembolism Pulmonary embolism Aortic dissection stroke Cerebral hemorrhage Myocardial infarction

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Standard intensity of anticoagulation<br>After mechanical valve replacement，patients should be gave oral anticoagulants，such as warfarin.and The intensity of anticoagulation for this group was standard intensity (INR:2.5-3.5). | Drug: Warfarin<br> <br> * Other names: Warfarin Sodium Tablets;|
| Low intensity and adjusted by elevated D-dimer<br>The intensity of anticoagulation maintained at low level initiatively, D-dimer testing were analyzed at 3 month later. In case of D-dimer level elevated, adjusted the intensity to standard level. | Drug: Warfarin<br> <br> * Other names: Warfarin Sodium Tablets;|
| Low intensity without adjustment<br>The intensity of anticoagulation for this group was kept at low intensity without adjustment (INR:1.8-2.6), | Drug: Warfarin<br> <br> * Other names: Warfarin Sodium Tablets;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bleeding Events; | The bleeding events included cerebral hemorrhage, gastrointestinal bleeding and other major internal or external bleeding that causes death, hospitalization, or permanent injury (e.g. vision loss) or necessitates transfusion. | Up to 24 months | 
| Thrombotic Events | The thrombotic events included valve thrombosis, transient ischemic attack, ischemic stroke, peripheral embolism, and myocardial infarction. | 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| All Cause Deaths | The deaths from all causes | Up to 24 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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mechanical valves replacement, INR, D-dimer, thromboembolic events