Clinical trial NCT01144819: Platelet Inhibition in the Acute Phase of STEMI
Official title: Platelet Inhibition in the Acute Phase of ST-segment Elevation Myocardial Infarction
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Acute Myocardial Infarction
Antiplatelet Therapy
ST-segment Elevation Myocardial Infarction (STEMI)
Keywords: STEMI
Acute myocardial infarction
Antiplatelet therapy
aspirin
clopidogrel
VerifyNow aggregometry
Multiplate aggregometry
Lead sponsor: University of Aarhus
Sponsor class: OTHER
Collaborators: name: AP Moeller Foundation
First posted: 2010-06-16
Enrollment: 46
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_ONLY
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Residents of the Central Denmark Region.

Brief summary: 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.


Eligibility 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.

Primary outcomes:
measure: Difference between aggregation induced by agonist collagen (1 μg/ml) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist collagen (1 μg/ml) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist collagen (1 μg/ml) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist arachidonic acid (1,0 mM) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist arachidonic acid (1,0 mM) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist arachidonic acid (1,0 mM) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist adenosine diphosphate (6,4 µM) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist adenosine diphosphate (6,4 µM) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist adenosine diphosphate (6,4 µM) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist adenosine diphosphate (20 µM) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist adenosine diphosphate (20 µM) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation induced by agonist adenosine diphosphate (20 µM) measured by Multiplate® Aggregometry (Unit=AUC).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation measured by VerifyNow® Aggregometry using the ASPI-kit (Unit = ARU).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation measured by VerifyNow® Aggregometry using the ASPI-kit (Unit = ARU).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation measured by VerifyNow® Aggregometry using the ASPI-kit (Unit = ARU).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation measured by VerifyNow® Aggregometry using the P2Y12-kit (Unit = PRU).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation measured by VerifyNow® Aggregometry using the P2Y12-kit (Unit = PRU).
timeFrame: Approximately 2-3 months
measure: Difference between aggregation measured by VerifyNow® Aggregometry using the P2Y12-kit (Unit = PRU).
timeFrame: Approximately 2-3 months
Secondary outcomes:
measure: Difference in immature platelet fraction measured by Sysmex® flowcytometry.
timeFrame: Approximately 2-3 months
measure: Difference in serum P-selectin
timeFrame: Approximately 2-3 months
measure: Difference in serum trombopoietin
timeFrame: Approximately 2-3 months
measure: Difference in serum thromboxane B2
timeFrame: Approximately 2-3 months
measure: Difference in immature platelet fraction measured by Sysmex® flowcytometry.
timeFrame: Approximately 2-3 months
measure: Difference in immature platelet fraction measured by Sysmex® flowcytometry.
timeFrame: Approximately 2-3 months
Other outcomes:
Locations:
city: Aarhus N
country: Denmark
facility: Aarhus University Hospital, Skejby
state: Central Denmark Region
Study officials:
affiliation: Aarhus University Hospital Skejby
name: Steen D Kristensen, MD, DMSc
role: PRINCIPAL_INVESTIGATOR
References:
citation: Funck-Jensen KL, Dalsgaard J, Grove EL, Hvas AM, Kristensen SD. Increased platelet aggregation and turnover in the acute phase of ST-elevation myocardial infarction. Platelets. 2013;24(7):528-37. doi: 10.3109/09537104.2012.738838. Epub 2012 Dec 5.