ThrombElastoGraphic Haemostatic Status and Antiplatelet Therapy After Coronary Artery Bypass Graft Surgery

Phase 3

• Conditions: Graft Patency; Coronary Artery Bypass Grafting Surgery; Hypercoagulability; Thrombosis
• Interventions: Drug: Clopidogrel+acetylsalicylic acid; Drug: acetylsalicylic acid

• Registration Number: NCT01046942
• Lead Sponsor: Rigshospitalet, Denmark

Brief Summary

The purpose of this study is to determine whether adding clopidogrel to aspirin after coronary bypass operation (CABG) improves graft patency, in patients that have preoperatively increased platelet activity(hypercoagulable) and therefore greater risk of graft occlusion( thrombosis).

Detailed Description

Graft patency after CABG is reported to 80-90% worldwide 1 year following surgery. In the immediate period after surgery, and the following month, graft occlusion mainly occurs due to thrombosis.

Patients with platelet hyperreactivity have increased risk of thromboembolic events, including graft occlusion, myocardial infarction and stroke. Therefore intensifying the antiplatelet therapy in these patients, must be anticipated to have beneficial effects.

Hypercoagulable patients are identified with thrombelastography(TEG) as having a Maximal Amplitude(MA)\>69, thereafter randomized to either clopidogrel(3months) and aspirin or aspirin alone. At 3 months postoperative after surgery the coronary graft patency is assessed with Multislice CT scan.

Pre- and postoperatively, and then again at 3month followup, TEG and multiplate aggregometry are performed to assess platelet reactivity and resistance to aspirin and clopidogrel.

Study Timeline

• Study Start: 2008-11
• Study First Submitted: 2010-01-11
• Study First Submitted QC: 2010-01-11
• Study First Posted: 2010-01-12
• Status Verified: 2013-09
• Last Update Submitted: 2013-09-23
• Last Update Posted: 2013-09-24
• Primary Completion: 2014-05
• Study Completion: 2014-09

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 250

Inclusion Criteria

• Elective/subacute multivessel CABG
• Isolated CABG procedure, no concomitant surgery
• age > 18 years
• Able to give informed consent

Exclusion Criteria

• Myocardial infarction <48h of surgery
• Prior CABG surgery within 1 month
• Cardiac Shock within 48h of surgery
• Atrial fibrillation
• Anticoagulation therapy with VKA
• ICH/TCI within 30 days
• Prior peptic ulcer· Platelet count < 150 E9
• Ongoing bleeding
• Known platelet disease
• Allergic to aspirin or clopidogrel
• Liver disease with elevated ALAT/ASAT> 1,5x normal
• Creatinine> 0,120mmol/l
• Contrast allergy
• Alcohol or narcotics abuse
• Pregnancy
• Not able to give informed consent
• Geographically not available for follow up

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Clopidogrel+Aspirin, hypercoagulabel	Clopidogrel+acetylsalicylic acid	-
Aspirin,hypercoagulabel control	acetylsalicylic acid	-

Primary Outcome Measures

Name	Time	Method
Graft patency at 3 months	3 months	Graft patency of Saphenous vein grafts will be significantly higher in TEG-Hypercoagulable patients on clopidogrel+aspirin vs. aspirin alone.

Secondary Outcome Measures

Name	Time	Method
Rate of other thromboembolic events( e.g. myocardial infarction,stroke, pulmonary embolus etc.)and cardiovascular death	3 months	In the TEG-Hypercoagulable intervention group (clopidogrel+aspirin) we expect significantly lower rates, of other thromboembolic events (e.g. myocardial infarction,stroke, pulmonary embolism etc) and cardiovascular death, compared to TEG-Hypercoagulable patients on aspirin monotherapy.
Assessing coagulation profile pre- and postoperatively, including aspirin and clopidogrel resistance	3 months

Trial Locations

Locations (1)

Dep. of cardiothoracic surgery, Rigshospitalet; 🇩🇰 Copenhagen, Kbh, Denmark