Very Low Dose Oral Anticoagulation and Thromboembolic and Bleeding Complications

Study Overview
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Brief Summary
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We aim to investiagte whether very low dose self management of oral anticoagulation is superior to low dose oral anticoagulation in order to prevent bleeding events in patients undergoing mechanuical heart valve replacement.

Detailed Description
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In mechanical heart valve recipients, self-management of oral anticoagulation can reduce the risk of developing thromboembolic events and improves long-term survival compared with international normalized ratio (INR) control by a general practitioner. Low-dose INR self-management (INR values of 1.8.-2.8 for aortic valve recipients and 2.5 - 3.5 for mitral or double valve recipients) does not increase the risk of thromboembolic events compared to conventional dose INR self-management. Even in patients with a low INR target range, however, the risk of bleeding events is still higher than the risk of thromboembolism. We therefore perform a prospective, randomized trial in 1,800 patients with mechanical heart valve replacement. During the first six postoperative months, low dose INR self-management will be performed by all patients (INR measurement once a week). Thereafter, 600 patients will continue with this treatment regimen, whereas the other 1,200 patients with perform very low dose oral anticoagulation. Out of these 1,200 patients, 600 will perform INR measurement once a week and 600 patients will perform INR measurement twice a week. Patients are followed up for 24 months.

Official Title
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Effects of Very Low Dose Oral Anticoagulation on Thromboembolism and Bleeding Events in Patients With Mechanical Heart Valve Replacement

Conditions
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Mechanical Heart Valve Recipients

Intervention / Treatment
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* Drug: phenprocoumon
* Drug: phenprocoumon
* Drug: phenprocoumon


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Mechanical heart valve recipients Exclusion Criteria: Contra-indication to phenprocoumon Ulcerous disease with bleeding tendency, Hypo- or hypercoagulability Dementia Missing informed consent

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: A<br>Low dose oral anticoagulation, INR self-management once a week | Drug: phenprocoumon<br>* The daily phenprocoumon dose administered should achieve an international normalized ratio (INR) of 1.8 - 2.8 for aortic valve recipients and 2.5 - 3.5 for mitral or double valve recipients, INR-self management once a week<br>|
| Active Comparator: B<br>very low dose oral anticoagulation, INR self-management once a week | Drug: phenprocoumon<br>* The daily phenprocoumon dose administered should achieve an international normalized ratio (INR) of 1.6-2.1 for aortic valve recipients and 2.0 - 2.5 for mitral or double valve recipients, INR self management once a week<br>|
| Experimental: C<br>very low dose oral anticoagulation, INR self-management twice a week | Drug: phenprocoumon<br>* The daily phenprocoumon dose administered should achieve an international normalized ratio (INR) of 1.6-2.1 for aortic valve recipients and 2.0 - 2.5 for mitral or double valve recipients, INR self management twice a week<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Thromboembolic events, Bleeding events, Survival rates |  | 2 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| INR values, Percent of INR values in the target range |  | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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phenprocoumon, INR self-management, mechanical heart valve replacement, bleeding, thromboembolism