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

Completed

Brief Summary: 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: 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.

Recruitment & Eligibility

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.

Arm && Interventions

Group	Intervention	Description
Standard intensity of anticoagulation	Warfarin	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).
Low intensity and adjusted by elevated D-dimer	Warfarin	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.
Low intensity without adjustment	Warfarin	The intensity of anticoagulation for this group was kept at low intensity without adjustment (INR:1.8-2.6),

Primary Outcome Measures

Name	Time	Method
Thrombotic Events	24 months	The thrombotic events included valve thrombosis, transient ischemic attack, ischemic stroke, peripheral embolism, and myocardial infarction.
Bleeding Events;	Up to 24 months	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.

Secondary Outcome Measures