Platelet Reactivity After CABG

Acute Coronary Syndrome Clinical Trial

Official title:

Platelet Activation, Reactivity, and Inflammation After Coronary Bypass Surgery In Patients Treated With Ticagrelor or Clopidogrel

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01793597
• Other study ID #: ISSBRIL0095
• Status: Completed
• Phase: N/A
• First received: February 13, 2013
• Last updated: September 20, 2015
• Start date: May 2013
• Est. completion date: September 2015

Study information

• Verified date: September 2015
• Source: University of Vermont
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Observational

Clinical Trial Summary

Patients who have a heart attack are regularly treated with either clopidogrel or ticagrelor. In a large clinical trial, treatment with ticagrelor before coronary bypass surgery (CABG) was associated with a lower risk of death than treatment with clopidogrel. The reason for this difference cannot be explained on the basis of the study. One possible explanation is that the reversible binding of ticagrelor is advantageous because when new platelets are released, they are inhibited by the drug. Because clopidogrel binds irreversibly it cannot redistribute. The investigators will recruit patients who are scheduled for surgery after an acute coronary syndrome who have been treated with either ticagrelor or clopidogrel. After the patient provides informed consent, the investigators will review their medical record,record information and on the day after surgery the investigators will take one sample of blood. That blood will be analyzed for evidence of platelet activation (platelet microparticles, and platelet-leukocyte aggregates), the reactivity of young platelets, and the concentration of inflammatory cytokines. The investigators hypothesize that the evidence of platelet activation (platelet microparticles and platelet-leukocyte aggregates) and the reactivity of young platelets will be less in patients who have been treated previously with ticagrelor.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 18
• Est. completion date: September 2015
• Est. primary completion date: September 2015
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Acute coronary syndrome, CABG, within 48 hours of last dose of clopidogrel or ticagrelor, treatment with aspirin

Exclusion Criteria:

• Treatment with an antiplatelet agent other than aspirin, clopidogrel, or ticagrelor, Acute or chronic hematologic disorder including a preoperative Hgb less than 10 g/dl or platelet count less than 100,000/mm3, Moderate or severe renal insufficiency (glomerular filtration rate less than 60 ml/min), Active infection, Active malignancy, Unable/unwilling to provide informed consent

Study Design

Observational Model: Cohort, Time Perspective: Prospective

Related Conditions & MeSH terms

• Acute Coronary Syndrome

Locations

Country	Name	City	State
United States	University of Vermont Medical Center	Burlington	Vermont

Sponsors (1)

Lead Sponsor	Collaborator
University of Vermont

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	reactivity of juvenile platelets	We will use flow cytometry to identify juvenile platelets and assess their likelihood to activate in response to a submaximal concentration of agonist.	16-24 hours after CABG	No
Secondary	platelet-leukocyte aggregates	We will identify the prevalence of platelet-leukocyte aggregates - a marker of platelet activation in vivo	16-24 hours after CABG	No
Secondary	platelet microparticles	We will quantify the prevalence of platelet microparticles, reflecting platelet activation in vivo	16-24 hours after CABG	No
Secondary	cytokine/chemokine array	We will quantify the concentration of common cytokines and chemokines.	16-24 hours after CABG	No