Coronary Artery Bypass Grafting Surgery, Graft Patency, Hypercoagulability, Thrombosis
Conditions
Keywords
Saphenous vein, Antiplatelet therapy, Hypercoagulable, Clopidogrel resistance, Aspirin resistance, Clopidogrel, Aspirin, Saphenous vein graft disease, TEG, Thrombelastography, Multiplate aggregometry, Multislice CT, Coronary artery bypass graft surgery, coagulation status, graft patency, CABG
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.
Interventions
DRUGClopidogrel+acetylsalicylic acid
loading dose clopidogrel 300mg on second postoperative day. Thereafter 75mg clopidogrel daily for 3 months Aspirin 75mg daily, started within 24 hours after surgery
DRUGacetylsalicylic acid
aspirin 75 mg daily, started 6-24 hours after surgery
Sponsors
Rigshospitalet, Denmark
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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
| Measure | Time frame | Description |
|---|---|---|
| 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 | — |
Countries
Denmark
Contacts
Primary ContactSulman Rafiq, MD
Backup ContactDaniel Steinbrüchel, Professor
Outcome results
None listed