Platelet Reactivity After CABG

Tracking Information
First Submitted Date	February 13, 2013
First Posted Date	February 15, 2013
Last Update Posted Date	September 22, 2015
Study Start Date	May 2013
Actual Primary Completion Date	September 2015 (Final data collection date for primary outcome measure)
Current Primary Outcome Measures; (submitted: February 14, 2013)	reactivity of juvenile platelets [ Time Frame: 16-24 hours after CABG ]; We will use flow cytometry to identify juvenile platelets and assess their likelihood to activate in response to a submaximal concentration of agonist.
Original Primary Outcome Measures	Same as current
Change History	Complete list of historical versions of study NCT01793597 on ClinicalTrials.gov Archive Site
Current Secondary Outcome Measures; (submitted: February 14, 2013)	platelet-leukocyte aggregates [ Time Frame: 16-24 hours after CABG ]We will identify the prevalence of platelet-leukocyte aggregates - a marker of platelet activation in vivo; platelet microparticles [ Time Frame: 16-24 hours after CABG ]We will quantify the prevalence of platelet microparticles, reflecting platelet activation in vivo; cytokine/chemokine array [ Time Frame: 16-24 hours after CABG ]We will quantify the concentration of common cytokines and chemokines.
Original Secondary Outcome Measures	Same as current
Current Other Outcome Measures	Not Provided
Original Other Outcome Measures	Not Provided
Descriptive Information
Brief Title	Platelet Reactivity After CABG
Official Title	Platelet Activation, Reactivity, and Inflammation After Coronary Bypass Surgery In Patients Treated With Ticagrelor or Clopidogrel
Brief 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.
Detailed Description	Not Provided
Study Type	Observational
Study Design	Observational Model: Cohort; Time Perspective: Prospective
Target Follow-Up Duration	Not Provided
Biospecimen	Retention: Samples Without DNA; Description: Platelets and leukocytes will be evaluated acutely. Plasma will be stored for cytokine and chemokine analysis.
Sampling Method	Non-Probability Sample
Study Population	Patients with acute coronary syndrome who based on clinical indications require urgent CABG. CABG is scheduled for clinical indications within 48 hours. Previous treatment with clopidogrel or ticagrelor.
Condition	Acute Coronary Syndrome
Intervention	Not Provided
Study Groups/Cohorts	clopidogrel previous treatment with clopidogrel; ticagrelor previous treatment with ticagrelor
Publications *	Not Provided
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status	Completed
Actual Enrollment; (submitted: September 20, 2015)	18
Original Estimated Enrollment; (submitted: February 14, 2013)	50
Actual Study Completion Date	September 2015
Actual Primary Completion Date	September 2015 (Final data collection date for primary outcome measure)
Eligibility Criteria	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
Sex/Gender	Sexes Eligible for Study: All
Ages	18 Years and older (Adult, Senior)
Accepts Healthy Volunteers	No
Contacts	Contact information is only displayed when the study is recruiting subjects
Listed Location Countries	United States
Removed Location Countries
Administrative Information
NCT Number	NCT01793597
Other Study ID Numbers	ISSBRIL0095
Has Data Monitoring Committee	No
U.S. FDA-regulated Product	Not Provided
IPD Sharing Statement	Not Provided
Responsible Party	David J. Schneider, MD, University of Vermont
Study Sponsor	University of Vermont
Collaborators	Not Provided
Investigators	Not Provided
PRS Account	University of Vermont
Verification Date	September 2015