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Thromboelastography As An Assessment Tool for Possible Clopidogrel and Aspirin Resistance (TEG)

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ClinicalTrials.gov Identifier: NCT00697021
Recruitment Status : Unknown
Verified April 2008 by Assaf-Harofeh Medical Center.
Recruitment status was:  Recruiting
First Posted : June 13, 2008
Last Update Posted : June 13, 2008
Information provided by:
Assaf-Harofeh Medical Center

June 10, 2008
June 13, 2008
June 13, 2008
June 2008
June 2009   (Final data collection date for primary outcome measure)
To determine usefulness of thromboelastography (TEG) as a valuable tool in assessing platelet response to clopidogrel treatment and post-treatment platelet reactivity during acute ST segment elevation myocardial infarction (STEMI). [ Time Frame: 0ne year follow up ]
Same as current
No Changes Posted
To determine the correlation between platelet response to clopidogrel treatment and the outcome of patients who underwent percutaneous coronary intervention (PCI) for STEMI. [ Time Frame: one year follow up ]
Same as current
Not Provided
Not Provided
Thromboelastography As An Assessment Tool for Possible Clopidogrel and Aspirin Resistance
Thromboelastography As An Assessment Tool for Possible Clopidogrel and Aspirin Resistance in The Patients Treated With Primary PCI for STEMI
TEG is an established technique to assess the quality of clot formation' used mainly in surgery and obstetrics to determine possible bleeding diathesis. Recently it became to be used in cardiology, where it can be a valuable tool to assess a response to antiplatelet therapy and its association with the outcome. However, there is a few data about use of TEG in STEMI patients undergoing PCI. Our study is designed to assess by TEG the platelet's response to clopidogrel treatment during acute STEMI in patients undergoing primary PCI and the correlation of this response with the long term outcome, and ability to dose adjustment according to a specific measurement by TEG in order to prevent future MACE.

TEG system may provide the capabilities needed to deliver personalized therapy, first, because it can identify patients at risk of ischemic event based on hemostatic influences, particularly platelet aggregation and platelet reactivity. Secondly, because treating those patients who exhibit high platelet reactivity -- an indication that they are not reaching a therapeutic level -- with appropriate drugs and doses is expected to improve outcomes.

In this study that would be increased clopidogrel maintenance dosing (150 mg) or aspirin maintenance dosing to 200mg in an attempt to lower platelet reactivity below the 50th%ile, which we expect to also reduce their ischemic risk during the follow up period.

Phase 3
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Prevention
Acute ST SEgment Elevation Myocardial Infarction
  • Drug: Aspirin (200mg) and/or Plavix (150mg) dosage according to TEG
    Non- responders to Aspirin or Plavix shown on TEG analysis will be treated by doubling of Aspirin (200mg) and/or Plavix (150mg) dosage
  • Drug: Aspirin 100mg and Plavix 75mg
    Responders to standard dual antiplatelet therapy as observed by TEG analysis will continue standard doses of Aspirin and Plavix
  • Active Comparator: 1
    Patients who suffered acute STEMI and were treated by PPCI and by Aspirin 100mg and Plavix 75mg and showed on treatment platelet over-reactivity observed by TEG system on the 5th day after admission to ICCU
    Intervention: Drug: Aspirin (200mg) and/or Plavix (150mg) dosage according to TEG
  • 2
    Patients who suffered acute STEMI and were treated by PPCI and recieved by Aspirin 100mg and Plavix 75mg and showed platelet inhibition observed by TEG system on the 5th day after admission to ICCU
    Intervention: Drug: Aspirin 100mg and Plavix 75mg
1. J Am Coll Cardiol. 2007 Feb 13;49(6):657-66. Epub 2007 Jan 26. Increased risk in patients with high platelet aggregation receiving chronic clopidogrel therapy undergoing percutaneous coronary intervention: is the current antiplatelet therapy adequate? Bliden KP, DiChiara J, Tantry US, Bassi AK, Chaganti SK, Gurbel PA. 2. J Am Coll Cardiol Vol. 49, No. 14, 2007 (1505-16) Variability in Individual Responsiveness to Clopidogrel Clinical Implications, Management, and Future Perspectives Dominick J. Angiolillo, MD, PHD, FACC,* Antonio Fernandez-Ortiz, MD, PHD,† Esther Bernardo, BSC,† Fernando Alfonso, MD, PHD,† Carlos Macaya, MD, PHD,† Theodore A. Bass, MD, FACC,* Marco A. Costa, MD, PHD, FACC* 3. Circulation. 2004 Jun 29;109(25):3171-5. Epub 2004 Jun 7. Clopidogrel resistance is associated with increased risk of recurrent atherothrombotic events in patients with acute myocardial infarction. Matetzky S, Shenkman B, Guetta V, Shechter M, Bienart R, Goldenberg I, Novikov I, Pres H, Savion N, Varon D, Hod H. 4. Ann Intern Med. 2007 Mar 20;146(6):434-41. Role of clopidogrel in managing atherothrombotic cardiovascular disease. Eshaghian S, Kaul S, Amin S, Shah PK, Diamond GA. 5. Eur Heart J. 2006 Oct;27(20):2420-5. Epub 2006 Sep 27. Low response to clopidogrel is associated with cardiovascular outcome after coronary stent implantation. Geisler T, Langer H, Wydymus M, Gohring K, Zurn C, Bigalke B, Stellos K, May AE, Gawaz M. 6. Curr Pharm Des. 2006;12(10):1261-9. Clopidogrel resistance: implications for coronary stenting. Gurbel PA, Lau WC, Bliden KP, Tantry US. 7. Semin Thromb Hemost. 2007 Mar;33(2):196-202. Variable response to clopidogrel in patients with coronary artery disease. Geisler T, Gawaz M. 8. Clin Res Cardiol. 2006 Feb;95(2):122-6. Epub 2006 Jan 19. Combined aspirin and clopidogrel resistance associated with recurrent coronary stent thrombosis. Templin C, Schaefer A, Stumme B, Drexler H, von Depka M. 9. Blood Coagul Fibrinolysis. 2007 Mar;18(2):187-92. Clinical relevance of aspirin resistance in patients with stable coronary artery disease: a prospective follow-up study (PROSPECTAR). Pamukcu B, Oflaz H, Onur I, Oncul A, Ozcan M, Umman B, Mercanoglu F, Meric M, Nisanci Y. 10. Am J Cardiol. 2006 Nov 20;98(10A):11N-17N. Epub 2006 Sep 28. Aspirin resistance or variable response or both? Cheng X, Chen WH, Simon DI.

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
Unknown status
October 2009
June 2009   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • Patients 18 years of age or more
  • Patients admitted with acute STEMI as a first Coronary event
  • Duration of symptoms less than 12 hours
  • PCI elected as a treatment of acute STEMI
  • Informed consent signed

Exclusion Criteria:

  • Thrombolytic therapy
  • PCI not performed after diagnostic angiography (conservative treatment, CABG)
  • DES used in PPCI
  • Staged PCI procedures
  • Previous clopidogrel treatment at any time for any reason
  • Previous myocardial infarction
  • Known bleeding diathesis of any kind
  • Significant renal insufficiency (GFR<40 ml/min)
  • LFT disturbances (Transaminase elevation more than x3 ULN)
  • Significant anemia (Hb<10) or a need for blood transfusion
  • Significant Thrombocytopenia (PLT Count < 150000)
  • Known Clopidogrel allergy
  • Known Active peptic disease
Sexes Eligible for Study: All
18 Years and older   (Adult, Senior)
Contact information is only displayed when the study is recruiting subjects
Not Provided
Not Provided
Alex Blatt MD, Intensive Coronary Care Unit Assaf Harofeh MC
Assaf-Harofeh Medical Center
Not Provided
Principal Investigator: Ilya Litovchik, MD Assaf Harofeh MC Heart Institue
Study Director: Alex Blatt, MD Assaf Harofeh MC ICCU Head of the Department
Assaf-Harofeh Medical Center
April 2008

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP