Transcranial Doppler (TCD) Assessment During Early Anti-thrombotic Therapy After Bioprosthetic Aortic Valve Replacement

NCT00465218 | Completed Results

• 1 other identifier: 2006785-01H
• Study Type: observational
• Target: 70
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to determine if there is any difference in the counts of cerebral emboli and platelet function between two prophylactic treatments of thrombosis currently used at University of Ottawa Heart Institute for the first three months after surgery in low-risk patients undergoing aortic valve replacement with a bioprosthetic valve: 1) daily use of high-dose aspirin \[325 mgs\], and 2) the combination of oral Warfarin \[target INR 2.0 to 3.0\] and low-dose aspirin \[81 mg\].

Conditions

Aortic Valve Disease

Keywords

Bioprosthesis; Thrombosis; Cerebral emboli; Transcranial Doppler; Platelet function tests

Outcome Measures

Primary Outcomes (1)

• Differences in the Rate of Doppler-detected Cerebral Micro Emboli Between the Two Prophylactic Treatments of Thrombosis

  Trans-cranial doppler (TCD) measurements were used to test for the presence of cerebral micro-emboli. Doppler measurements were completed on the neck and throughout the temporal window. In addition, probes were secure to the temporal areas with a headband. Measurements determined presence of air or solid emboli. Each participant at the 1 month visit underwent TCD measurements after 30min of exposure to room air, and again 30min after receiving 100% oxygen through a breathing mask. Results show the comparison of participants on aspirin only vs warfarin + aspirin when TCD was completed both in room air and with 100% oxygen.

  1 month after surgery

Secondary Outcomes (2)

• Differences in the Degree of Inhibition of Platelet Aggregation Between the Two Prophylactic Treatments of Thrombosis

  1 month after surgery

• Difference in the Degree of Inhibitor of Platelet Aggregation Between the Two Prophylactic Treatments of Thrombosis

  1 month after surgery

Study Arms (2)

1

High dose aspirin (325 mg)

Procedure: Prophylaxis of Thrombosis after aortic valve replacement

2

Low dose aspirin (81 mgs) plus warfarin

Procedure: Prophylaxis of Thrombosis after aortic valve replacement

Interventions

Prophylaxis of Thrombosis after aortic valve replacement PROCEDURE

Two standard prophylactic treatments of thrombosis within the first 3 months postsurgery currently used in our institution: a) daily dose of aspirin (325 mgs; b) daily dose of aspirin (81 mg) plus Warfarin for target INR 2.0-2.5

1; 2

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients with aortic valve stenosis and/or insuficiency undergoing aortic valve replacement with a bioprosthetic valve (tissue valve).

You may qualify if:

• Patients undergoing primary aortic valve replacement with bioprosthetic (tissue) valve.

You may not qualify if:

• Emergency surgery or redo operations.
• Patients with history of transient ischemic attacks, stroke, or history of carotid stenosis greater than 50% as detected by carotid duplex doppler or angiography.
• Patients with COPD who are CO2 retainers.
• Patients with LV function less than 50%, or enlarged left ventricle greater than 50 mm as detected by echocardiography or previous history of thromboembolism.
• Patients with history of atrial fibrillation or heart rhythm disturbances.

Sponsors & Collaborators

• Ottawa Heart Institute Research Corporation: lead
• Edwards Lifesciences: collaborator

Study Sites (1)

University of Ottawa Heart Institute

Ottawa, Ontario, K1Y 4W7, Canada

Location

Related Publications (12)

• Gohlke-Barwolf C, Acar J, Oakley C, Butchart E, Burckhart D, Bodnar E, Hall R, Delahaye JP, Horstkotte D, Kremer R, et al. Guidelines for prevention of thromboembolic events in valvular heart disease. Study Group of the Working Group on Valvular Heart Disease of the European Society of Cardiology. Eur Heart J. 1995 Oct;16(10):1320-30. doi: 10.1093/oxfordjournals.eurheartj.a060739. No abstract available.

  PMID: 8746900 BACKGROUND

• ACC/AHA guidelines for the management of patients with valvular heart disease. A report of the American College of Cardiology/American Heart Association. Task Force on Practice Guidelines (Committee on Management of Patients with Valvular Heart Disease). J Am Coll Cardiol. 1998 Nov;32(5):1486-588. doi: 10.1016/s0735-1097(98)00454-9. No abstract available.

  PMID: 9809971 BACKGROUND

• Stein PD, Alpert JS, Bussey HI, Dalen JE, Turpie AG. Antithrombotic therapy in patients with mechanical and biological prosthetic heart valves. Chest. 2001 Jan;119(1 Suppl):220S-227S. doi: 10.1378/chest.119.1_suppl.220s.

  PMID: 11157651 BACKGROUND

• Kirtane AJ, Rahman AM, Martinezclark P, Jeremias A, Seto TB, Manning WJ. Adherence to American College of Cardiology/American Heart Association guidelines for the management of anticoagulation in patients with mechanical valves undergoing elective outpatient procedures. Am J Cardiol. 2006 Mar 15;97(6):891-3. doi: 10.1016/j.amjcard.2005.09.139. Epub 2006 Feb 2.

  PMID: 16516596 BACKGROUND

• Heras M, Chesebro JH, Fuster V, Penny WJ, Grill DE, Bailey KR, Danielson GK, Orszulak TA, Pluth JR, Puga FJ, et al. High risk of thromboemboli early after bioprosthetic cardiac valve replacement. J Am Coll Cardiol. 1995 Apr;25(5):1111-9. doi: 10.1016/0735-1097(94)00563-6.

  PMID: 7897124 BACKGROUND

• Moinuddeen K, Quin J, Shaw R, Dewar M, Tellides G, Kopf G, Elefteriades J. Anticoagulation is unnecessary after biological aortic valve replacement. Circulation. 1998 Nov 10;98(19 Suppl):II95-8; discussion II98-9.

  PMID: 9852888 BACKGROUND

• Gherli T, Colli A, Fragnito C, Nicolini F, Borrello B, Saccani S, D'Amico R, Beghi C. Comparing warfarin with aspirin after biological aortic valve replacement: a prospective study. Circulation. 2004 Aug 3;110(5):496-500. doi: 10.1161/01.cir.0000137122.95108.52.

  PMID: 15289387 BACKGROUND

• Rodriguez RA, Rubens F, Rodriguez CD, Nathan HJ. Sources of variability in the detection of cerebral emboli with transcranial Doppler during cardiac surgery. J Neuroimaging. 2006 Apr;16(2):126-32. doi: 10.1111/j.1552-6569.2006.00035.x.

  PMID: 16629734 BACKGROUND

• Zimmermann N, Roussiekan T, Winter J, Kurt M, Gams E, Wenzel F, Hohlfeld T. Platelet inhibition by aspirin after aortic valve replacement. J Thorac Cardiovasc Surg. 2006 Jun;131(6):1392-3. doi: 10.1016/j.jtcvs.2006.01.029. No abstract available.

  PMID: 16733175 BACKGROUND

• Geiser T, Sturzenegger M, Genewein U, Haeberli A, Beer JH. Mechanisms of cerebrovascular events as assessed by procoagulant activity, cerebral microemboli, and platelet microparticles in patients with prosthetic heart valves. Stroke. 1998 Sep;29(9):1770-7. doi: 10.1161/01.str.29.9.1770.

  PMID: 9731593 BACKGROUND

• Sturzenegger M, Beer JH, Rihs F. Monitoring combined antithrombotic treatments in patients with prosthetic heart valves using transcranial Doppler and coagulation markers. Stroke. 1995 Jan;26(1):63-9. doi: 10.1161/01.str.26.1.63.

  PMID: 7839399 BACKGROUND

• Markus HS, Thomson ND, Brown MM. Asymptomatic cerebral embolic signals in symptomatic and asymptomatic carotid artery disease. Brain. 1995 Aug;118 ( Pt 4):1005-11. doi: 10.1093/brain/118.4.1005.

  PMID: 7655877 BACKGROUND

Related Links

• Publications indexed to this study

MeSH Terms

Conditions

Aortic Valve Disease; Thrombosis; Intracranial Embolism

Condition Hierarchy (Ancestors)

Heart Valve Diseases; Heart Diseases; Cardiovascular Diseases; Embolism and Thrombosis; Vascular Diseases; Intracranial Embolism and Thrombosis; Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Thromboembolism

Results Point of Contact

• Title: Dr. Marc Ruel
• Organization: University of Ottawa Heart Institute

mruel@ottawaheart.ca

613-696-7288

Study Officials

• Marc Ruel, MD, MPH

  Ottawa Heart Institute Research Corporation

  PRINCIPAL INVESTIGATOR

• Thierry Mesana, MD, PhD

  Ottawa Heart Institute Research Corporation

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 20, 2007
• First Posted: April 24, 2007
• Study Start: March 1, 2007
• Primary Completion: December 1, 2007
• Study Completion: March 1, 2011
• Last Updated: May 22, 2026
• Results First Posted: May 22, 2026

Record last verified: 2021-03

Locations

CA (1)