Randomized On-X Anticoagulation Trial (PROACT)

On-X Life Technologies

Status: Active, not recruiting

Conditions: Heart Valve Disease

Treatments: Device: On-X Valve with Standard warfarin Therapy; Device: On-X valve using reduced anticoagulation

Study type: Interventional

Funder types: Industry; Other

Identifiers

NCT00291525

G050208 (Other Identifier)

2005-01

Details and patient eligibility

About

Various patient groups with the On-X Valve can be maintained safely on lower doses of blood thinner(Coumadin®) or on antiplatelet drugs (aspirin/Plavix®) only rather than the standard dose of Coumadin and aspirin presently recommended by ACC/AHA or ACCP professional societies.

Full description

This is a longitudinal, randomized (randomization to occur at the 3-month follow-up) study comparing the On-X valve on low dose anticoagulation (test group) to concomitant control groups of On-X valves receiving standard Coumadin/aspirin therapy, and also to FDA objective performance criteria (OPC) for heart valve replacement. It is a multicenter study consisting of up to 50 centers in the United States, Canada, and Italy enrolling and randomizing no more than 1200 patients (200 in each of 6 groups). There are three test arms of the study: low risk aortic valve replacement, high risk aortic valve replacement, and mitral valve replacement. Each arm has an equivalent control. Test therapies are: low risk aortic valve replacement - aspirin/Plavix, high risk aortic valve replacement - Coumadin at INR of 1.5 to 2.0 plus aspirin, and mitral valve replacement - Coumadin at an INR of 2.0 to 2.5 plus aspirin. Follow-up will run for up to 8 years in each patient. Each arm is independent and the low risk aortic and high risk aortic arms are completed. The low risk aortic arm was closed early resulting in a reduction of the estimated total enrollment with randomization to 1000. The high risk arm is completed with FDA review and this arm had 375 randomized enrollees. The mitral arm continues to enroll with a planned randomized enrollment of 400.

Enrollment: 1,200 estimated patients

Sex: All

Ages: 18 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients requiring isolated aortic valve replacement (AVR), or isolated mitral valve replacement (MVR).

• AVR patients receiving low dose or antiplatelet only anticoagulation will be divided into groups at low risk and high risk for thromboembolism with all patients being in the low risk group except for patients with the following conditions which place a patient in the high risk group:

  • Chronic atrial fibrillation
  • Left ventricular ejection fraction < 30 %
  • Enlarged left atrium >50mm diameter
  • Spontaneous echo contrasts in the left atrium
  • Vascular pathology
  • Neurological events
  • Hypercoagulability
  • Left or right ventricular aneurysm
  • Lack of platelet response to aspirin or clopidogrel
  • Women receiving estrogen replacement therapy

• Concomitant cardiac surgery is allowed

• Adult patients

Exclusion criteria

• Right side valve replacement
• Double (aortic plus mitral) valve replacement
• Patients with active endocarditis at the time of implant
• Previous confirmed or suspected thromboembolic event or thrombophlebitis
• Other terminal illness
• Patients who are in an emergency state
• Inability to return for required follow-ups
• Patients with an On-X valve implanted within the study and subsequently explanted
• Patients who are known to be pregnant, plan to become pregnant or are lactating
• Patients with acquired immunodeficiency syndrome or know to be HIV positive
• Patients who are prison inmates or known drug or alcohol abusers
• Patients unable to give adequate informed consent.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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1,200 participants in 6 patient groups

AVR Low Risk without warfarin

Experimental group

Description:

AVR Low Risk without warfarin

Treatment:

Device: On-X valve using reduced anticoagulation

AVR low risk with standard warfarin

Active Comparator group

Description:

AVR low risk with standard warfarin

Treatment:

Device: On-X Valve with Standard warfarin Therapy

AVR High risk with lower warfarin

Experimental group

Description:

AVR High risk with lower warfarin

Treatment:

Device: On-X valve using reduced anticoagulation

AVR High Risk with standard warfarin

Active Comparator group

Description:

AVR High Risk with standard warfarin

Treatment:

Device: On-X Valve with Standard warfarin Therapy

MVR with lower warfarin

Experimental group

Description:

MVR with lower warfarin

Treatment:

Device: On-X valve using reduced anticoagulation

MVR with standard warfarin

Active Comparator group

Description:

MVR with standard warfarin

Treatment:

Device: On-X Valve with Standard warfarin Therapy