Ignite Creation Date:
2024-05-05 @ 5:30 PM
Last Modification Date:
2024-10-26 @ 9:32 AM
Study NCT ID:
NCT00465218
Status:
COMPLETED
Last Update Posted:
2012-06-21
First Post:
2007-04-20
Brief Title:
Transcranial Doppler TCD Assessment During Early Anti-thrombotic Therapy After Bioprosthetic Aortic Valve Replacement
Sponsor:
Ottawa Heart Institute Research Corporation
Organization:
Ottawa Heart Institute Research Corporation
Study Overview
Official Title:
Transcranial Doppler Assessment of Cerebral Embolization During Early Anti-thrombotic Therapy After Bioprosthetic Aortic Valve Replacement Comparison of High-dose Aspirin Versus Warfarin Plus Low-dose Aspirin
Status:
COMPLETED
Status Verified Date:
2012-06
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
Tissue-Valve
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 20 to 30 and low-dose aspirin 81 mg
Detailed Description:
Background
There are several medications used to prevent blood clotting in patients undergoing surgical replacement of their aortic valves with tissue valves One of these medications is called warfarin Coumadin which prevents blood clotting by making the blood thinner Another medication is aspirin which prevents the aggregation clustering of cells in the blood called platelets Some clinicians consider that using only aspirin should be enough to protect the patients against the presence of clots in the blood but others consider that aspirin should be combined with warfarin for better protection Moreover physicians express concern over the use of oral anticoagulation due to the possibility of an increased risk of bleeding The effects of these medications for preventing blood clots traveling to the brain after the surgery are currently unknown Transcranial doppler ultrasound will be used in these patients to evaluate non-invasively the quantity of fragments of clots circulating in the arteries of the brain In addition platelet function will be measured to determine how effective these treatments are for preventing the aggregation of the blood cells called platelets which may be involved in clot formation
Objective
Our purpose 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 in our institution for the first three months after surgery in these patients 1 daily use of high-dose aspirin 325 mgs and 2 the combination of oral Warfarin target INR 20 to 30 and low-dose aspirin 81 mg
Methods
Patients with low risk profile undergoing primary aortic valve replacement with a bioprosthetic tissue valve will be eligible for the study Patients will receive one of the two prophylactic treatments of thrombosis 1 or 2 depending on the surgeons preference Platelet function will be measured before surgery and transcranial doppler within the first 24 hours immediately after the surgery At the end of one month following surgery all patients will undergo transcranial doppler and platelet function assessment The study will be powered on demonstrating the hypothesis of substantial equivalence between the two treatments as regarding the primary outcome cerebral emboli
Outcome measures
1 Primary outcome
Bilateral counts of cerebral emboli in the middle cerebral arteries with transcranial doppler ultrasound at one month after surgery
2 Secondary outcomes
Platelet function incidence of major adverse neurologic and bleeding events at one month following surgery
There are several medications used to prevent blood clotting in patients undergoing surgical replacement of their aortic valves with tissue valves One of these medications is called warfarin Coumadin which prevents blood clotting by making the blood thinner Another medication is aspirin which prevents the aggregation clustering of cells in the blood called platelets Some clinicians consider that using only aspirin should be enough to protect the patients against the presence of clots in the blood but others consider that aspirin should be combined with warfarin for better protection Moreover physicians express concern over the use of oral anticoagulation due to the possibility of an increased risk of bleeding The effects of these medications for preventing blood clots traveling to the brain after the surgery are currently unknown Transcranial doppler ultrasound will be used in these patients to evaluate non-invasively the quantity of fragments of clots circulating in the arteries of the brain In addition platelet function will be measured to determine how effective these treatments are for preventing the aggregation of the blood cells called platelets which may be involved in clot formation
Objective
Our purpose 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 in our institution for the first three months after surgery in these patients 1 daily use of high-dose aspirin 325 mgs and 2 the combination of oral Warfarin target INR 20 to 30 and low-dose aspirin 81 mg
Methods
Patients with low risk profile undergoing primary aortic valve replacement with a bioprosthetic tissue valve will be eligible for the study Patients will receive one of the two prophylactic treatments of thrombosis 1 or 2 depending on the surgeons preference Platelet function will be measured before surgery and transcranial doppler within the first 24 hours immediately after the surgery At the end of one month following surgery all patients will undergo transcranial doppler and platelet function assessment The study will be powered on demonstrating the hypothesis of substantial equivalence between the two treatments as regarding the primary outcome cerebral emboli
Outcome measures
1 Primary outcome
Bilateral counts of cerebral emboli in the middle cerebral arteries with transcranial doppler ultrasound at one month after surgery
2 Secondary outcomes
Platelet function incidence of major adverse neurologic and bleeding events at one month following surgery
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None