Platelet Inhibition in the Acute Phase of STEMI

This study has been completed.
Sponsor:
Collaborator:
AP Moeller Foundation
Information provided by (Responsible Party):
University of Aarhus
ClinicalTrials.gov Identifier:
NCT01144819
First received: March 26, 2010
Last updated: September 6, 2013
Last verified: September 2013
  Purpose

Background:

Dual antithrombotic treatment with aspirin and clopidogrel is recommended in patients with ST elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). The European Society of Cardiology (ESC) Guidelines recommend a bolus dose of aspirin of 250-500 mg and a 600 mg bolus dose of clopidogrel as soon as STEMI is suspected. Studies have shown that more newly produced platelets are present in the acute phase of STEMI, and it is likely that these immature platelets are haemostatically more active and might be of importance in thrombus formation.

The enhanced platelet reactivity may reduce the effect of aspirin and clopidogrel in the acute phase of STEMI compared to measurements made in the same patients 3 months after primary PCI.

Aim:

This study aims to compare platelet response to aspirin and clopidogrel in the acute phase of STEMI with the platelet response in the same patients 3 months after STEMI .

Design:

This study is an observational follow-up study.

Materials and methods:

46 patients with STEMI referred to primary PCI at Aarhus University Hospital, Skejby will be included in the study. A total of 3 blood samples are obtained in the acute phase of STEMI: Prior to primary PCI (Blood sample 1), at 4 hours (Blood sample 2) and at 12 hours (Blood sample 3) after administration of loading dose aspirin and clopidogrel. When patients are in a stable phase 3 month later, a final blood sample is taken (Blood sample 4). The blood is analyzed 30 minutes after withdrawal of blood by the platelet aggregation test Multiplate® aggregometry (agonists: Collagen, arachidonic acid and adenosinediphosphate) and VerifyNow® arachidonic acid and P2Y12 aggregometry. Platelet count, volume and the immature platelet fraction (IPF) will be measured using Sysmex® flowcytometry.


Condition
Acute Myocardial Infarction
Antiplatelet Therapy
ST-segment Elevation Myocardial Infarction (STEMI)

Study Type: Observational
Study Design: Observational Model: Case-Only
Time Perspective: Prospective
Official Title: Platelet Inhibition in the Acute Phase of ST-segment Elevation Myocardial Infarction

Resource links provided by NLM:


Further study details as provided by University of Aarhus:

Primary Outcome Measures:
  • Difference between aggregation induced by agonist collagen (1 μg/ml) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 1: Obtained immediately before primary PCI in the catherization laboratory. The blood sample is obtained from the femoral artery catheter.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist collagen (1 μg/ml) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 2: 4 hours after administration of loading dose (LD) aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist collagen (1 μg/ml) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 3: 12 hours after administration of LD aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist arachidonic acid (1,0 mM) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 1: Obtained immediately before primary PCI in the catherization laboratory. The blood sample is obtained from the femoral artery catheter.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist arachidonic acid (1,0 mM) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 2: 4 hours after administration of loading dose (LD) aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist arachidonic acid (1,0 mM) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 3: 12 hours after administration of LD aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist adenosine diphosphate (6,4 µM) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 1: Obtained immediately before primary PCI in the catherization laboratory. The blood sample is obtained from the femoral artery catheter.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist adenosine diphosphate (6,4 µM) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 2: 4 hours after administration of loading dose (LD) aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist adenosine diphosphate (6,4 µM) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 3: 12 hours after administration of LD aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist adenosine diphosphate (20 µM) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 1: Obtained immediately before primary PCI in the catherization laboratory. The blood sample is obtained from the femoral artery catheter.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist adenosine diphosphate (20 µM) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 2: 4 hours after administration of loading dose (LD) aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation induced by agonist adenosine diphosphate (20 µM) measured by Multiplate® Aggregometry (Unit=AUC). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 3: 12 hours after administration of LD aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation measured by VerifyNow® Aggregometry using the ASPI-kit (Unit = ARU). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 1: Obtained immediately before primary PCI in the catherization laboratory. The blood sample is obtained from the femoral artery catheter.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation measured by VerifyNow® Aggregometry using the ASPI-kit (Unit = ARU). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 2: 4 hours after administration of loading dose (LD) aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation measured by VerifyNow® Aggregometry using the ASPI-kit (Unit = ARU). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 3: 12 hours after administration of LD aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation measured by VerifyNow® Aggregometry using the P2Y12-kit (Unit = PRU). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 1: Obtained immediately before primary PCI in the catherization laboratory. The blood sample is obtained from the femoral artery catheter.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation measured by VerifyNow® Aggregometry using the P2Y12-kit (Unit = PRU). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 2: 4 hours after administration of loading dose (LD) aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference between aggregation measured by VerifyNow® Aggregometry using the P2Y12-kit (Unit = PRU). [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between aggregation measurements. In this case between:

    Blood sample 3: 12 hours after administration of LD aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.



Secondary Outcome Measures:
  • Difference in immature platelet fraction measured by Sysmex® flowcytometry. [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between measurements. In this case between:

    Blood sample 1: Obtained immediately before primary PCI in the catherization laboratory. The blood sample is obtained from the femoral artery catheter.

    Blood sample 4: 2-3 months after administration of LD aspirin and clopidogrel.


  • Difference in serum P-selectin [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between measurements. In this case between:

    Blood sample 1: Obtained immediately before primary PCI in the catherization laboratory. The blood sample is obtained from the femoral artery catheter.

    Blood sample 4: 2-3 months after administration of LD aspirin and clopidogrel.


  • Difference in serum trombopoietin [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between measurements. In this case between:

    Blood sample 1: Obtained immediately before primary PCI in the catherization laboratory. The blood sample is obtained from the femoral artery catheter.

    Blood sample 4: 2-3 months after administration of LD aspirin and clopidogrel.


  • Difference in serum thromboxane B2 [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between measurements. In this case between:

    Blood sample 1: Obtained immediately before primary PCI in the catherization laboratory. The blood sample is obtained from the femoral artery catheter.

    Blood sample 4: 2-3 months after administration of LD aspirin and clopidogrel.


  • Difference in immature platelet fraction measured by Sysmex® flowcytometry. [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between measurements. In this case between:

    Blood sample 2: 4 hours after administration of loading dose (LD) aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.


  • Difference in immature platelet fraction measured by Sysmex® flowcytometry. [ Time Frame: Approximately 2-3 months ] [ Designated as safety issue: No ]

    Outcome is the difference between measurements. In this case between:

    Blood sample 3: 12 hours after administration of LD aspirin and clopidogrel.

    Blood sample 4: 2-3 months after primary PCI.



Biospecimen Retention:   Samples With DNA

Blood sample 1:

  • Whole blood (Platelet aggregation tests and flowcytometry)
  • Serum
  • S-Thromboxane B2
  • S-Trombopoeitin
  • S-P-selectin
  • Plasma
  • DNA
  • RNA

Blood sample 2:

  • Whole blood
  • Plasma

Blood sample 3:

  • Whole blood
  • Plasma

Blood sample 4:

  • Whole blood (Platelet aggregation tests and flowcytometry)
  • Serum
  • S-Thromboxane B2
  • S-Trombopoeitin
  • S-P-selectin
  • Plasma
  • DNA
  • RNA

Enrollment: 46
Study Start Date: October 2009
Study Completion Date: August 2010
Primary Completion Date: July 2010 (Final data collection date for primary outcome measure)
Groups/Cohorts
STEMI
Patients with STEMI according to ESC STEMI guidelines: Age above 18 years and able to give written, informed consent to participation in the project.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population

Residents of the Central Denmark Region.

Criteria

Inclusion Criteria:

  • Above 18 years of age
  • Patients with ST-segment elevation myocardial infarction (STEMI) referred to primary PCI at University Hospital of Aarhus, Skejby.

Exclusion Criteria:

  • Treatment with NSAID, ticlopidine and dipyramidole.
  • Treatment with anticoagulants (Vitamin K antagonists)
  • Patients diagnosed with platelet disease or haemophilia.
  • Patients unable to give written, informed consent to participation in this project.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01144819

Locations
Denmark
Aarhus University Hospital, Skejby
Aarhus N, Central Denmark Region, Denmark, 8200
Sponsors and Collaborators
University of Aarhus
AP Moeller Foundation
Investigators
Principal Investigator: Steen D Kristensen, MD, DMSc Aarhus University Hospital Skejby
  More Information

Publications:
Responsible Party: University of Aarhus
ClinicalTrials.gov Identifier: NCT01144819     History of Changes
Other Study ID Numbers: 23374
Study First Received: March 26, 2010
Last Updated: September 6, 2013
Health Authority: Denmark: The Regional Committee on Biomedical Research Ethics
Denmark: Danish Dataprotection Agency

Keywords provided by University of Aarhus:
STEMI
Acute myocardial infarction
Antiplatelet therapy
aspirin
clopidogrel
VerifyNow aggregometry
Multiplate aggregometry

Additional relevant MeSH terms:
Infarction
Myocardial Infarction
Cardiovascular Diseases
Heart Diseases
Ischemia
Myocardial Ischemia
Necrosis
Pathologic Processes
Vascular Diseases

ClinicalTrials.gov processed this record on October 30, 2014